wow, thanks for the good info. deff planed on throwing a full tuneup on it trhis weekend,also gonna set the the distributer back where it should be, then i think im gonna hard wire a light on a toggle into my dash, so i can just flip the toggle and jump ports and watch the codes flash from inside the car, once i get the codes pulled ill posr the results up, also gonna try to get it in the air and get a good look at the underside and see how the o2 sensors look as far as wiring and throw a new fuel filter on it. also how hard is it to do a maf conversion? ive heard people run maf for low end and have it phase into the sd for the top end, how doable and efficent is this? looking for my best bang for my buck. thanks for any and all help, im a noob to this.
Over Fueling.
- Thread starter michigan_fox
- Start date
-
Sponsors (?)
Maf is a super simple setup. It's also a completely different operating system. It will replace your sd ecu.
Speed Density uses Manifold vacuum (MAP), Throttle position (TPS) and RPM, Air Temperature (ACT) & Engine Coolant (ECT) to guess how much air the engine is pulling in. Then it uses all of them to calculate the air/fuel mixture. It is dependent on steady manifold vacuum and minimal changes in airflow from the stock engine configuration to maintain the proper air/fuel ratio. Change the airflow or vacuum too much and the computer can't compensate for the changes, and does not run well. Forget about putting a supercharger, turbocharger or monster stroker crank in a Speed Density engine, because the stock computer tune won’t handle it. Every time you seriously change the airflow through the engine, you need a new custom burned chip to make the engine run at peak performance.
Mass Air uses a Mass Air Flow meter (MAF) to actually measure how much air is being pulled into the engine. The computer uses this information and inputs from the TPS, ACT, ECT, RPM and Barometric Pressure sensor (Baro) to calculate the proper air/fuel ratio. It is very tolerant of changes in airflow and vacuum and tolerates wild cams, high flowing heads, and changes in displacement with minimal difficulties. Larger injectors can be used with an aftermarket calibrated MAF or a custom dyno tune. This makes it possible to use the stock computer with engine displacements from 302-408 cu in, and make many modifications without a custom dyno tune chip. Put a new intake manifold on your 331 stroker and the computer figures out how much more fuel to deliver without having to have a new chip burned to accommodate the extra airflow.
MASS air conversion instructions from http://www.stangnet.com/tech/maf/massairconversion.html FREE
A9L (5 Speed) computer from junkyard $100-$150
A9P (Auto or in a pinch, it will work in a 5 Speed car) computer from junkyard $100-$150
70MM MAF from 94-95 Mustang GT - $40-$70
MASS Air wiring harness kit $30-$85
The whole thing is probably less than $300 using junkyard parts.
A9L computers are 5 speed only
A9P computers are automatic, but will work with a 5 speed.
The conversion harness seems to work well for most folks. It avoids the compatibility problems in using a harness from the junkyard. Simple and cheap, actually less work that swapping the wiring harness.
Conversion Harness kits & parts
http://www.mass-air.com/
http://oldfuelinjection.com/index.php?p=54
If the idea of moving & soldering wires scares you, here's a list of compatible Mass Air wiring harnesses.
Copied from bbunt302
Just for reference, here's a list of all the compatible years:
89 harness should work for 86-89 as long as you're using mass air.
90 harness will only work in a 90. (B/c of air bags and dual dash connectors)
91 through early 92 harnesses should be compatible (single dash connector, fuel pump relay under driver's seat)
Late 92 through 93 harnesses should be compatible (single dash connector, fuel pump relay under the hood)
Larger MAF to go with Mass Air conversion:
94-95 Mustang GT MAF - $40-$100. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2
*1.) Metal flange adapter http://www.kustomz.com/cat3.html Buy the TR70 for $40-$45 depending on if it’s on sale or not. Or spend some time on eBay looking for one that may fit.
Try AutoZone and ask for 81413 - Spectre / 3 in. Aluminum Intake Mass Air Flow Sensor Adapter at $12.00. You may have to order it online.
*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.
Also see www.forfuelinjection.com for help with the harness parts http://rjminjectiontech.com/?p=10, and connector pins, http://rjminjectiontech.com/?p=11
Mass Air uses a Mass Air Flow meter (MAF) to actually measure how much air is being pulled into the engine. The computer uses this information and inputs from the TPS, ACT, ECT, RPM and Barometric Pressure sensor (Baro) to calculate the proper air/fuel ratio. It is very tolerant of changes in airflow and vacuum and tolerates wild cams, high flowing heads, and changes in displacement with minimal difficulties. Larger injectors can be used with an aftermarket calibrated MAF or a custom dyno tune. This makes it possible to use the stock computer with engine displacements from 302-408 cu in, and make many modifications without a custom dyno tune chip. Put a new intake manifold on your 331 stroker and the computer figures out how much more fuel to deliver without having to have a new chip burned to accommodate the extra airflow.
MASS air conversion instructions from http://www.stangnet.com/tech/maf/massairconversion.html FREE
A9L (5 Speed) computer from junkyard $100-$150
A9P (Auto or in a pinch, it will work in a 5 Speed car) computer from junkyard $100-$150
70MM MAF from 94-95 Mustang GT - $40-$70
MASS Air wiring harness kit $30-$85
The whole thing is probably less than $300 using junkyard parts.
A9L computers are 5 speed only
A9P computers are automatic, but will work with a 5 speed.
The conversion harness seems to work well for most folks. It avoids the compatibility problems in using a harness from the junkyard. Simple and cheap, actually less work that swapping the wiring harness.
Conversion Harness kits & parts
http://www.mass-air.com/
http://oldfuelinjection.com/index.php?p=54
If the idea of moving & soldering wires scares you, here's a list of compatible Mass Air wiring harnesses.
Copied from bbunt302
Just for reference, here's a list of all the compatible years:
89 harness should work for 86-89 as long as you're using mass air.
90 harness will only work in a 90. (B/c of air bags and dual dash connectors)
91 through early 92 harnesses should be compatible (single dash connector, fuel pump relay under driver's seat)
Late 92 through 93 harnesses should be compatible (single dash connector, fuel pump relay under the hood)
Larger MAF to go with Mass Air conversion:
94-95 Mustang GT MAF - $40-$100. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2
*1.) Metal flange adapter http://www.kustomz.com/cat3.html Buy the TR70 for $40-$45 depending on if it’s on sale or not. Or spend some time on eBay looking for one that may fit.
Try AutoZone and ask for 81413 - Spectre / 3 in. Aluminum Intake Mass Air Flow Sensor Adapter at $12.00. You may have to order it online.
*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.
Also see www.forfuelinjection.com for help with the harness parts http://rjminjectiontech.com/?p=10, and connector pins, http://rjminjectiontech.com/?p=11
f8tlfiveo
My wife likes my spool and blow-off valve.
Where did you see this? Never heard of that before. You have to swap to a Maf computer to complete the swap. I did mine on my 88 pretty cheap. Ran my own wiring instead of buying a new harness. There are instructions on this site on how to do it. But I prob did it for 150 or less.. Buy the parts used.
Wicked50Chris
Member
First you need to tune it up, change the timing chain, clean the IAC, and DEFIANTLY get 2 o2 sensors and hook them up. Adjust your timing. Get it to run right before you get into the conversion. Then get the codes and post here and everyone will help you out, just like they did for me 
Not having the O2 sensors in there is defiantly causing you to run rich or lean. They play a huge role. The po of my car was a hack to. Car came with NO O2 sensors, or even the damn harness. First thing i did was get them. Car ran better. But it had way more "hack" issues, that have been fixed, and OMG does it run great. Good luck bro.
Not having the O2 sensors in there is defiantly causing you to run rich or lean. They play a huge role. The po of my car was a hack to. Car came with NO O2 sensors, or even the damn harness. First thing i did was get them. Car ran better. But it had way more "hack" issues, that have been fixed, and OMG does it run great. Good luck bro.
Er....what?
Just focus on getting the car to great running condition. Ignore with the OP told you and do your own research on the car. First thing to do is to run the check engine codes because 1987's do not have a working check engine light.
Get the codes, and go from there.
Speed density is perfectly capable. No reason to run out and swap to MAF just yet. Fix your issues first, and then focus on the swap later. I have plenty of mods on my car and still running speed density and it runs smooth and reliable.
i think the car is hit, i jumped the gun and ended up with someones ragged out pile of 
. plugs looked oil fouled to me, black and wet. did full tune up, tried setting timing by ear, got the idle smoother and not running as rich, but now it lacks power. gonna get a test light tomorrow to scan codes, but im guessing its a junk motor, if it idles in the grass and you rev it, it leaves big spots of black, same in paved driveway. also notticed today the oil pressure seems to have dropped, its just hanging onto the L on normal.
. plugs looked oil fouled to me, black and wet. did full tune up, tried setting timing by ear, got the idle smoother and not running as rich, but now it lacks power. gonna get a test light tomorrow to scan codes, but im guessing its a junk motor, if it idles in the grass and you rev it, it leaves big spots of black, same in paved driveway. also notticed today the oil pressure seems to have dropped, its just hanging onto the L on normal.
That sucks to hear. Most of us have been there. Honestly iv would try and unload it as quickly as possible.
and those gauges are known not to be accurate regarding the pressure it
may be low but not as low as you
think and the motor may still be ok
Sent from my iPhone using my fingers
may be low but not as low as you
think and the motor may still be ok
Sent from my iPhone using my fingers
koeo codes. coolant temp sensor out of specific range, map out of specific range, tps out of specific range, lean fuel mixture at wide open throttle, egr not operating properly, fuel mixture rich. koer codes. thermactor air circuit/integrated controller circuit, tps out of specific range, thermactor air circuit, low speed fuel pump relay, tps or circuit, evap volt above closed unit. all these codes and there all sensors..wonder if this motor was put in and hacked wireing by previous owner.
Here i seperated them and made them easier to read. Maybe jrichker will chime in soon.
As far as the timing , dude you need a timing light and you need to set it that way spout disconnected to 10*
koeo codes.
coolant temp sensor out of specific range
map out of specific range
tps out of specific range,
lean fuel mixture at wide open throttle
egr not operating properly
fuel mixture rich
koer codes.
thermactor air circuit/integrated controller circuit,
tps out of specific range,
thermactor air circuit,
low speed fuel pump relay,
tps or circuit,
evap volt above closed unit.
all these codes and there all sensors..wonder if this motor was put in and hacked wireing by previous owner.
As far as the timing , dude you need a timing light and you need to set it that way spout disconnected to 10*
koeo codes.
coolant temp sensor out of specific range
map out of specific range
tps out of specific range,
lean fuel mixture at wide open throttle
egr not operating properly
fuel mixture rich
koer codes.
thermactor air circuit/integrated controller circuit,
tps out of specific range,
thermactor air circuit,
low speed fuel pump relay,
tps or circuit,
evap volt above closed unit.
all these codes and there all sensors..wonder if this motor was put in and hacked wireing by previous owner.
i know it needs to be timed with a light, but only one i found was 100 bucks, so im waiting on a buddy to bring his by, but it was advanced as far as you could turn it, so i just asjusted it to where it sounded like it had a smoother idle and wasnt running rich, i realize its not accurate but has to netter than where it was, when ou say spout disconnected do you mean to unplug the elextrical connector?
jetmech807
10 Year Member
I'd still check the timing chain. I've had one skip a tooth. Car still started and idled ok, just no bottom end. Also seen four cylinders skip a tooth on the belt and still idle and run. Only problem was no bottom end and pushing alot of unburned gas out of the exhaust, due to the severely retarded cam/ignition timing. If it has skipped a tooth, it will skip another and then the best case it will just quit running, worst case the pistons will start tagging the valves.
Sent from my EVO using Tapatalk 2
Sent from my EVO using Tapatalk 2
Similar threads
