Bad exhaust gasses / emission test failed

grayvixen93

Member
Oct 15, 2020
20
10
13
Altea
Hi!
This is my first post :)

I have a 93 GT Vert.

I did not pass the smog/emission test because of bad gases - lambda was 1.28 at 3000 rpm.

I brought the car to a workshop in my town after I sealed some exhaust leaks. There was a big leak on the pipe that leads to the smog pump.
I thought this must have been the issue as the leak was in front of the catalytic converters so I just wanted to get my gases tested.

Before I brought the car to the workshop I did also smoke-test the exhaust system as well as the vacuum lines in the engine bay to make sure there's no other leak.
I could only see smoke coming out of the holes of the EGR valve (the ones that point direction throttle body) as long as the throttle "butterfly" was closed. On "wide open" there was no more smoke exiting the EGR valve.

I did a rebuild of the car in the last 7 months.

Engine parts I changed:

* fuel pump
* bigger throttle body (the water inlets original TB had been rusted and I already had a bigger new TB incl. spacer at home)
* water distributor tube on top of the engine (had a massive hole)
* water pump + gaskets
* thermostat + gaskets
* gaskets for timing chain housing
* new silicone water hoses (all)
* new heater core
* new original Ford spark plug wires
* new hoses for the charcoal canister - self-made :)

* fresh gas
* new oil filter and new oil

I removed the valve covers and the intake but did NOT install new gaskets as the old ones still looked fine to me.

I checked for leaks by spraying engine starter spray around the gasket area but the engine did not rev up.

I set the idle based on this video:
View: https://youtu.be/T-T0Ry7VmA0


The engine itself is stock.
I only have a cold air intake with the stock air mass meter.

The guys in the workshop said today (2 days later after I dropped the car off) they have no idea about that car and need to gather information.
They told me they think it might be the fuel pump, the fuel filter, or the fuel jets that create bad exhaust gasses.

I am a hobby mechanic but completely lost at the moment.
I am quite worried that these guys might mess up my car by not knowing where to start and what to do.

Do you have any idea if they could be right or do you think it could be even something completely different?
 
  • Sponsors (?)


There are a bunch of things that could cause bad exhaust fumes. Fuel pump would be an unusual cause unless you have e driving issues...like bucking or stalling. You can check the vacuum hose coming off the fuel pressure regulator to the intake for fuel. It should be dry and not smell like raw fuel.

I've never replaced an upper intake without changing the gasket. Never seen one look good after taking it off. They are usually paper or graphite and crush to seal.

Do you have good catalytic converters ?

Pull the codes...or have the shop pull the codes. If they can't pull the codes get your car away from there as fast as you can.
 
  • Agree
Reactions: 1 user
Before I brought the car to the workshop I did also smoke-test the exhaust system as well as the vacuum lines in the engine bay to make sure there's no other leak.
I could only see smoke coming out of the holes of the EGR valve (the ones that point direction throttle body) as long as the throttle "butterfly" was closed. On "wide open" there was no more smoke exiting the EGR valve.


That should not happen. Remove the EGR valve and check to see if the plunger is stuck open, or gunked up that it doesn't create a good seal.

I assume you are in spain? Difficult to get parts there?
 
  • Agree
Reactions: 1 user
There are a bunch of things that could cause bad exhaust fumes. Fuel pump would be an unusual cause unless you have e driving issues...like bucking or stalling. You can check the vacuum hose coming off the fuel pressure regulator to the intake for fuel. It should be dry and not smell like raw fuel.

I've never replaced an upper intake without changing the gasket. Never seen one look good after taking it off. They are usually paper or graphite and crush to seal.

Do you have good catalytic converters ?

Pull the codes...or have the shop pull the codes. If they can't pull the codes get your car away from there as fast as you can.
Thanks for your reply!

I do not have driving issues so I would also scratch the fuel pump from the list.
The vacuum hose could be an option as this one snapped and I "fixed" it with a shrink tube and electrical tape. I don't know if that worked but I did not have any gas smell coming from the engine bay. Replacing this vacuum line is already on my list but this will take some time as getting parts from the US is quite a pain :(.

I will go and get my car today as I do not want them to do any additional "work". I will ask them if they pulled the codes. If not I will pull the codes later and report if there are any.

The cats had been sitting the last three years in my basement, not being mounted on the car. 3 years ago they had been fine. Is there a way to test/see if they are bad?
 
That should not happen. Remove the EGR valve and check to see if the plunger is stuck open, or gunked up that it doesn't create a good seal.

I assume you are in spain? Difficult to get parts there?
Thanks for your reply!

I will check the EGR valve later when I have my car back. I also have a spare EGR valve at home so I could also try this one.

I am living in Spain and getting parts is a pain and quite expensive regarding shipping, toll, and taxes as I usually order everything directly in the US (RockAuto, LMR, American Muscle, CJ Pony Parts).

It would be nice to have a junkyard around where you can pull parts - but foxbodies are more than rare :D
 
I just got back from the workshop.

Before I report what they said here some impressions:

IMG_2817.jpg


The front bumper got messed up!!! The entire car was just painted!!! Looks like they did hit a post. Apologies from the mechanic? Nope! Instead, he said that the car is lowered and he had to take care not to hit the curb as he parked the car outside the shop this morning...

IMG_2818.jpg


Big oil runner on top of the hood! The car was parked below another car. Apologies from the mechanic? Again: nope!

IMG_2819.jpg


Oil runner removed by the mechanic with a rough and dry paper towel.


To be honest: The car still needs a nice buff but in my opinion, he still should have removed the oil runner carefully!

So, now I have to keep the car still there because the big boss has to inspect the bumper to make sure the "issue" it was not already there before.

I will go back in 4 hours and the report.

The mechanic said that he assumes the fuel pressure is too low or the fuel filter is reducing the pressure.
Do you know what the fuel pressure should be like?

They said they also pulled the codes but the mechanic who did that was not yet in the shop this morning.
They said they will give me the codes later as well.
 
What does the car being lowered have to do with running it into something 18 inches off the ground. Thats BS. I hope they make it right for you. Can you not get vacuum line material at your local auto parts store? That isn't a mustang specific thing. Just in case the shop doesn't give you the codes your computer is throwing here is a link to a post that will walk you through the process of pulling the codes.

 
What does the car being lowered have to do with running it into something 18 inches off the ground. Thats BS. I hope they make it right for you.
They will take off the front bumper. They wanted to keep the car in their shop over the weekend. Bad idea :D I took the car and told them I will bring them the front bumper as I do not want them to touch the car anymore.
Can you not get vacuum line material at your local auto parts store?
Good idea. I will do this later or tomorrow.

They did not pull the codes. As I asked again they said they were talking about the fuel pressure. They said they think it was something around 2.8 bars what is about 40 psi. No idea how they tested the pressure.

The mechanic said the fuel was smelling very old. I just filled the tank 2 days ago with fresh fuel from the gas station.
In March, as I started with the rebuild, I cleaned the entire tank and kept it drying for a month or so outside.
In April I only filled it once with about 5 gallons.

Any idea why the gas could smell "old"?
 
Last edited:
Old lines or an old filter maybe? :shrug: It sounds to me like these guys are just grabbing at anything and dont really know what they are doing. You can follow the process outlined in the link I posted earlier to pull codes using a paper clip or you can buy a code reader off of Amazon for a few dollars. They are cheap. Here is an example of a code reader.

Amazon product ASIN B000EW0KHWView: https://www.amazon.com/INNOVA-3145-Ford-Digital-Reader/dp/B000EW0KHW/ref=sr_1_5?dchild=1&keywords=obd1+scanner&qid=1602857415&sr=8-5
 
  • Like
Reactions: 1 user
I'm glad you picked your car up from that shop. A vacuum leak can cause your issue. Timing could also do this. A lot of people don't know to put the PIP sensor before setting the timing. Its a little box plugged into a connector located off of the distributor connector between it and the AC compressor. You have to remove it to set the timing.

We had a trip planned to Greece and Italy this year but the virus prevailed. Next year maybe.
 
Hi!
This is my first post :)

I have a 93 GT Vert.

I did not pass the smog/emission test because of bad gases - lambda was 1.28 at 3000 rpm.

I brought the car to a workshop in my town after I sealed some exhaust leaks. There was a big leak on the pipe that leads to the smog pump.
I thought this must have been the issue as the leak was in front of the catalytic converters so I just wanted to get my gases tested.

Before I brought the car to the workshop I did also smoke-test the exhaust system as well as the vacuum lines in the engine bay to make sure there's no other leak.
I could only see smoke coming out of the holes of the EGR valve (the ones that point direction throttle body) as long as the throttle "butterfly" was closed. On "wide open" there was no more smoke exiting the EGR valve.

I did a rebuild of the car in the last 7 months.

Engine parts I changed:

* fuel pump
* bigger throttle body (the water inlets original TB had been rusted and I already had a bigger new TB incl. spacer at home)
* water distributor tube on top of the engine (had a massive hole)
* water pump + gaskets
* thermostat + gaskets
* gaskets for timing chain housing
* new silicone water hoses (all)
* new heater core
* new original Ford spark plug wires
* new hoses for the charcoal canister - self-made :)

* fresh gas
* new oil filter and new oil

I removed the valve covers and the intake but did NOT install new gaskets as the old ones still looked fine to me.

I checked for leaks by spraying engine starter spray around the gasket area but the engine did not rev up.

I set the idle based on this video:
View: https://youtu.be/T-T0Ry7VmA0


The engine itself is stock.
I only have a cold air intake with the stock air mass meter.

The guys in the workshop said today (2 days later after I dropped the car off) they have no idea about that car and need to gather information.
They told me they think it might be the fuel pump, the fuel filter, or the fuel jets that create bad exhaust gasses.

I am a hobby mechanic but completely lost at the moment.
I am quite worried that these guys might mess up my car by not knowing where to start and what to do.

Do you have any idea if they could be right or do you think it could be even something completely different?

How to pass emissions testing:

High NO - high combustion temps - retard timing, check EGR for operation.
High CO – Rich condition - fuel pressure too high, check O2 sensors, replace air filter, Clean MAF element.
High HC – Lean misfire, vacuum leak, common misfire due to worn or weak ignition system components. On rare occasions, an overly rich mixture may be the cause. Do the ethanol/E10 fill up as suggested.
High CO & HC - Cat converters, smog pump, and smog pump controls. Make sure the smog pump has good air output at 1200-1700 RPM

How to pass emissions testing:

1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats. The smog tech will do a visual check to make sure that all the original equipment is present and connected up.

2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.

Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

Foxbody Diagnostic connector

foxbody-mustang-diagnostic-connector-jpg.586766


Foxbody Diagnostic connector close up view


foxbody-diagnostic-connetor-closeup-view-jpg.586765


If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

583777.gif


The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

583778.gif


The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10
4




Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Reader/dp/B000EW0KHW Equus - Digital Ford Code Reader 3145.
Or for a nicer scanner see www.midwayautosupply.com/Equus-Digital-Ford-Code-It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.

Order it at Walmart for a better price and free shipping

41P3GQVDSHL._SS270_.jpg



Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, clutch depressed to the floor and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.
Cylinder balance test
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 9 for everything OK, or the number of the failing cylinder such as 2 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures.
Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure



4.) Post the codes and get help to fix them. Don’t try to pass with codes not fixed. Clearing the computer just temporarily removes them from memory, it doesn’t fix the problem that caused the code to be set.

5.) Be sure to do the testing on a hot engine. Drive for 15-20 minutes prior to taking the test to get operating temps up into the normal range. Do not shut off the engine while waiting for your turn on the test machine. An engine up to full operating temperature puts out fewer emissions.
 
Full disclosure - I buzzed through this thread pretty quick (in case I repeat something).

Glad you got that car out of there! If it were me, I wouldn’t even let them fix their mistake!

As you can see, there is ton of knowledge on this site, and even more people willing to help! If you have the skills, and the patience, I guarantee the info is here to get your car running right!

If you’re like a lot of us, working on the car is more of the fun than driving! Dig in, fix things step by step, and stand back knowing you didn’t pay anyone to do it!

good luck!
 
  • Like
  • Love
Reactions: 1 users
I'm glad you picked your car up from that shop. A vacuum leak can cause your issue. Timing could also do this. A lot of people don't know to put the PIP sensor before setting the timing. Its a little box plugged into a connector located off of the distributor connector between it and the AC compressor. You have to remove it to set the timing.

We had a trip planned to Greece and Italy this year but the virus prevailed. Next year maybe.
Timing will be on my list tomorrow. I just got myself a gun so I hope I will be able to do that :) Will need to watch some videos tonight on Youtube :)

I will also smoke test the vacuum lines again.

More info on my progress in a separate reply :)

We planned to come to the US for a longer period this summer, then rescheduled for the end of October until the end of November but the virus also crashed into our plans...
 
  • Like
Reactions: 1 user
How to pass emissions testing:

High NO - high combustion temps - retard timing, check EGR for operation.
High CO – Rich condition - fuel pressure too high, check O2 sensors, replace air filter, Clean MAF element.
High HC – Lean misfire, vacuum leak, common misfire due to worn or weak ignition system components. On rare occasions, an overly rich mixture may be the cause. Do the ethanol/E10 fill up as suggested.
High CO & HC - Cat converters, smog pump, and smog pump controls. Make sure the smog pump has good air output at 1200-1700 RPM

How to pass emissions testing:

1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats. The smog tech will do a visual check to make sure that all the original equipment is present and connected up.

2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.

Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

Foxbody Diagnostic connector

?temp_hash=124ae0e661fe7ed48f0bcc9e908d5b73.jpg


Foxbody Diagnostic connector close up view


?temp_hash=124ae0e661fe7ed48f0bcc9e908d5b73.jpg


If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

583777.gif


The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.

583778.gif


The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
See AutoZone Part Number: 25886 , $10
4




Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Reader/dp/B000EW0KHW Equus - Digital Ford Code Reader 3145.
Or for a nicer scanner see www.midwayautosupply.com/Equus-Digital-Ford-Code-It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $22-$36.

Order it at Walmart for a better price and free shipping

41P3GQVDSHL._SS270_.jpg



Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, clutch depressed to the floor and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.
Cylinder balance test
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 9 for everything OK, or the number of the failing cylinder such as 2 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures.
Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure



4.) Post the codes and get help to fix them. Don’t try to pass with codes not fixed. Clearing the computer just temporarily removes them from memory, it doesn’t fix the problem that caused the code to be set.

5.) Be sure to do the testing on a hot engine. Drive for 15-20 minutes prior to taking the test to get operating temps up into the normal range. Do not shut off the engine while waiting for your turn on the test machine. An engine up to full operating temperature puts out fewer emissions.
Thanks for your detailed instruction!!!
I did follow step by step.

I had two codes: 34 and 66.

I looked them up here in the forum. 66 is related to the MAF. I found another thread here in the forum where you explained how to deal with Code 66. I did follow most steps but I did not yet check the resistance between the MAF and the computer.

I checked the voltage as described on pins C & D but at idle I did not read .6 volts. Instead, it was between .78 and 1.04 volts.

The resistance between A & C was > 10k ohms (I think it was around 30k).

I replaced the MAF with a used one that I pulled from my donor car (91 Mercury Cougar). Before I installed it I cleaned it with an air intake cleaner. After that, I tested the outputs on the pins C & D again and the reading was now between .88 and 1.0 volts at idle.

I did test the EGR by blowing into the vacuum nipple and it seemed to be ok. I will test it tomorrow again with my smoke tester. I have a spare EGR (used) and could also pull the EGR from my donor - in case I need to troubleshoot this valve. Can I keep the current gasket in case I want to change the EGR valve? The EGR was installed with a new gasket about 2 months ago but the engine was not really running a lot.

After that, I pulled codes again followed by pulling the engine running codes and performed the cylinder balance test. Here my results:

Engine not running: Code 66 was gone, Code 34 still present.
Engine running (first test): Code 21 and Code 34
Cylinder balance test: Code 9
Engine running (second test): Code 21 was gone, Code 34 remained.

After these tests, I tested the fuel pressure at idle. I did measure 34 psi.

The engine is not really running smoothly but I have also no car to compare it to.
My donor does not run anymore because I already removed too many parts :D

I could upload a video where you maybe could hear the engine :)


Idle after "new" MAF was installed. I might have to do the base idle reset again?
IMG_2847.jpg




Today I also got a set of new spark plugs. I will install them tomorrow.
 
  • Like
Reactions: 1 user
Sunday update

Today I changed my spark plugs. The new ones are from Bosch and have a gap of .06.
I read in the forum that the gap should usually be around .52. I hope that the spark plugs are still ok.

As the spark plugs already were out I tested the compression. All cylinders were between 120 & 130 psi.

Then I did a base idle reset.
TPS @ engine not running: 1.00 volts
TPS @ engine running: 1.03 volts

I replaced the EGR.

Result: all error codes are gone, the car idles very smooth.

Thank you all so much for helping out!!!

Tomorrow I will get the front bumper fixed.
Once I have it back I will go back for the emissions test. I will keep you posted
 
Last edited:
  • Like
Reactions: 3 users
Sunday update

Today I changed my spark plugs. The new one are from Bosch and have a gap of .06.
I read in the forum that the gap should usually be around .52. I hope that the spark plugs are still ok.

As the dork plugs already were out I tested the compression. All cylinders were between 120 & 130 psi.

Then I did a base idle reset.
TPS @ engine not running: 1.00 volts
TPS @ engine running: 1.03 volts

I replaced the EGR.

Result: all error codes are gone, the car idles very smooth.

Thank you all so much for helping out!!!

Tomorrow I will get the front bumper fixed.
Once I have it back I will go back for the emissions test. I will keep you posted
Nice man! Glad to hear you got it running well.
 
  • Clever
Reactions: 1 user
I just came back from the emission test. Failed again.
The technician said he felt exhaust gases in front of the mufflers and said this might also be the reason for the bad emission.

Back at home, I pulled the error codes: 34 was back again.

I already replaced the EGR valve including the sensor, that is bolt onto it.

BTW: Pulling codes starts with 11, then, after 11 shows twice I see the check engine flashing once and after that, it shows me twice 34.

I was already looking for 34 codes here in the forum and found an answer of @jrichker
EGR blow test passed. EGR is already replaced (used part).

I tested the resistance between the black/white wire of the MAP/BARO sensor and ...
-> ... the black/white wire of the EGR: < 1 ohm
-> ... the black/white wire of the TPS: < 1 ohm
-> ... the negative battery post: > 1 ohm (1.34 kohm)

How can I fix that? Could this cause code 34?
Is there anything else I can do with code 34?

Should I clean my O2 sensors? They are quite new (less than 2k miles).

Could I test if the catalytic converters are bad?

Charcoal canister: could this guy also affect the emissions? I cleaned it while I was rebuilding the car (dumped liquid - one hose was gone).

I passed the last emission test about 600 miles ago with the same cats.

The only upgrade I made since then:

- 70mm throttle body + spacer incl. TPS (was included in the TB)
- cold air intake

The pics of these parts:

image.jpg

image.jpg

Pic from the emission test:

794FD9E1-D342-4967-8962-FD2F05A8CAAE.jpeg
 
Last edited:
I did seal the exhaust pipes before and after the mufflers. Then I performed a smoke test: no leak visible. Smoke went all the way to the other tip (tested both sides). So would assume the exhaust system has no leaks.

I did check the timing and did adjust it to 10 degrees BTDC (SPOUT connector was removed). I did not do a base idle/TPS reset.

After that I pulled the codes again (KOEO) - only code 11, no saved codes.
Then I pulled the code with engine running - only code 11.

I did replace the hose from the vacuum tree (under the intake) to the charcoal canister as this hose is seemed to be wrong - was completely flat (looked like a snake that got run over).

Then I went back to get the emission tested again.
Result: failed again. This time the lambda value (here they only care about this value) was even worse: 1.52 (max allowed: 1.03) in idle. HC was something around 40 and higher.

Back at home I pulled the codes again: only code 11.

What would you try next.