Larocca's doesn't know how to fix my 93. WTF????

OK...Had my car tuned at another shop. They tuned the car with O2 sensors. Results are still the same as far as catalytic converters go. They are still glowing.

I had my exhaust gases analyzed without catalytic converters just so everyone can see why the smell that I am complaining about is extremely crazy.
I expected the EGA readings to be higher than the excepted limit for a mustang to pass inspection due to the fact that I have an aftermarket cam that is not CARB certified and the fact that I am taking readings without catalytic converters. BUT the readings of HCs at idle is why I think my catalytic converters are glowing

Here are the results:

--------------Idle (900 RPM)---------1500 RPM-----------2500 RPM


HC--------------2135-----------------316------------------160

CO---------------1.44-----------------.88-------------------.67

CO2--------------11.2-----------------13.2-----------------13.6

O2-----------------1.3------------------1.6------------------1.3

NOX---------------117------------------123-----------------159
 
  • Sponsors (?)


Here is some additional info that I gathered. A/F is supposedly good at idle 14.7:1 or very close to it But I did not actually verify this with my own eyes

Compression- 8.7:1
Idle- 900 RPMs
Plugs- Autolite 3924 (.035 gap)
Fuel Pressure at idle - 42# (49 w/vacuum line disconnected)
Vacuum- 12 Hg/In at idle (measured via boost gauge)
Timing- 10 BTDC
TPS Voltage- .99
Water temp- 179 (when exhaust gas analysis was taken)

Engine Management- EEC-IV w/Autologic chip
Ignition- Crane HI6-TRC
Coil- MSD Blaster TFI
Wires- Accel 300 Race
Injectors- 42#
MAF- 80 Pro-M (Supercharger calibrated)
Cam- Comp Cam Custom grind .547/.555 220/236 115 LSA
Heads- Edelbrock Performer RPM (1.90/1.60)
Intake- Edelbrock Performer RPM
Headers- FRPP Ceramic
Exhaust- 2.5” offroad


No Smog Pump
No EGR Valve
PCV is connected
One breather in each valve cover
 
Welcome back to last year...sorry :D

Strange how the HC drops as soon as it comes off idle...Almost like to much fuel at idle..Verify the A/F ratio at idle and see what it does with some RPM...

Maybe closed or is it open loop when the ECU dumps fuel in when the motors cold at idle ???

179 is a little cool for the temp. Ford recommends 195 degrees...

Still shooting in the dark...Just some ideas...

Good luck...
 
Pop-Pops-Pony said:
Welcome back to last year...sorry :D

Strange how the HC drops as soon as it comes off idle...Almost like to much fuel at idle..Verify the A/F ratio at idle and see what it does with some RPM...

Maybe closed or is it open loop when the ECU dumps fuel in when the motors cold at idle ???

179 is a little cool for the temp. Ford recommends 195 degrees...

Still shooting in the dark...Just some ideas...

Good luck...

I will look into a couple of things. Every little bit of info helps and I appreciate it. I need all the help I can get. This really sucks ya know?
 
13 + months and still trying...I feel for ya...

Ya know i'm almost thinking the injectors might be to big for your setup...At idle their putting out to much fuel (even with a short firing time) and when the rpm comes up it gets to a point where the injectors are feeding the proper amount of fuel for the motor to burn completely...42#'s are pretty hefty...Even if other people run them successfully...

Shame you can't find a set of 30's or even 24's and a mass air to fit and try it...Or did you already try ?? I forget...
 
I had a problem when i bought my first stang sort of like this... This might be a little off topic. Heres the scoop i bought my car and when the car would heat up the cats would get extremely hott. Now when you would drive it for a while some how fuel would get into the exauhst. Then the fuel would ignite causing the mufflers to explode. So i took it to six different garages. Finally one garage said it was running really rich because of something with the valve seats or something i dont really remember and it had a large ammount of blowby and something else on top of that. He told me right out(best thing he could of ever done) sell the car or buy a new engine because a rebuild isnt 100% and theres no guarantee. So i bought a used engine and the car ran fine there after. Maybe there is a possibility of more then one problem that is being over looked.
 
Pop-Pops-Pony said:
13 + months and still trying...I feel for ya...

Ya know i'm almost thinking the injectors might be to big for your setup...At idle their putting out to much fuel (even with a short firing time) and when the rpm comes up it gets to a point where the injectors are feeding the proper amount of fuel for the motor to burn completely...42#'s are pretty hefty...Even if other people run them successfully...

Shame you can't find a set of 30's or even 24's and a mass air to fit and try it...Or did you already try ?? I forget...

I hear what you are saying. When I had 24's n/a I experienced the same issue I am having now with blower and 42's. Obviously maf's have been changed each time to match injector size. I think it may be camshaft related (too much overlap) or possibly computer related. Nevrtherless, I will get this car fixed.
 
My sincere apologies go to the entire crew at Larocca's Performance.

Larocca's and I are going to try and resolve my issue in a professional manner. Things will get worked out between us.

This post was started a while back to get suggestions from Corral members in hopes of a resolution to my issue. During this time the post may have turned "non-technical". Without going back and reading through the entire post I apologize for any negative remarks/comments directed torwards Larocca's Performance.

I appreciate any and all suggestions from everyone.
 
My cats glow red too, it has something to do with the tune..richness/leanness...I am figuring out the prob with my mechanic, plus when i let it idle for 10 mins in the garage they glow, when i drive it they dont glow because they are getting cooled by the air flowing under the car..
 
I was under the impression Laraccos was one of the best shops on the east coast.Though I did hear of one story,,my buddies friend brought it there for a few dyno runs.Well they finished and sent him on his way without locking the locks on his lift off hood.At about 45mph it blew off and they wouldnt re-emberse him for anything!!
 
slvr302 said:
My sincere apologies go to the entire crew at Larocca's Performance.

Larocca's and I are going to try and resolve my issue in a professional manner. Things will get worked out between us.

This post was started a while back to get suggestions from Corral members in hopes of a resolution to my issue. During this time the post may have turned "non-technical". Without going back and reading through the entire post I apologize for any negative remarks/comments directed torwards Larocca's Performance.

I appreciate any and all suggestions from everyone.

you are trully a class act for doing the above...... I have dealt with LaRocca's a few times and couldnt be any happier with there service and the way they have treated me. They get the job done :nice:
 
Daggar said:
I sure hope you didn't drag up this thread just to say that you have one just like it.

lol he did, but Id like to know if he ever got the problem fixed :shrug: What happened? Ive read like 3 of the pages haha im already into it

Maybe his ACT sensor is bad? :lol:
 
billson... if you not the original poster had already changed his cats a few times, you have not... also you didn't get one the best shops in the country to look at it for you soo go swap your cats and see if that fixes it, if not we'll be here offering moe solutions