Running Way Too Rich

5.0ttops87

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Nov 12, 2016
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So my 87 gt has a e303, gt-40 intake, 1.7 rr, new lifters (stock replacement), hardened pushrods, shorty headers.. I've tried a million different things here.. I've gotten the car timed to a 10 and plugged the spout connector back in and it ran fine till i tried to drive it and once it warmed up or ran longer it only seemed to idle worse (not just lope.. surge off and on).

Things I've already replaced/checked -

*New Cap/rotor (msd)
*Tried a few different pair of spark plug wires...
*New spark plugs (NGK G-power)
*Checked voltage on Throttle Position Sensor (.98 closed - 3.4 open all the way)
*Vacuum to Fuel Pressure Regulator (and a few month old fuel pressure regulator in the car)
*New vacuum line to MAP sensor (good vacuum there)
*New/used fuel injectors (stock 19# off ebay.. I tried 30# and it really ran rich as heck)

Side note - I know its running pig rich because it'll foul plugs pretty quickly.. and it burns my eyes with smoke in the garage..

Also I do not have the O2s hooked up yet.. I know this could be helpful but i haven't had time to take my xpipe in to have new bungs welded in.

Any suggestion?
 
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I don't quite get how people say to dump the codes on the computer... but I do have a scan tool for my car..
Codes Pulled - 22- Manifold Absolute Pressure (map) sensor out of range... I checked the vacuum and such.. it seemed good.. it wasn't getting any before i replaced the line.. but is good now....
54 - Intake Air Charge temperature sensor circuit open/vaine air flow out of range
85
10
18 - SPOUT circuit open or Spark Angle Word (SAW) circuit failure.. or Loss of Tachometer inpute/ IDM circuit failure/ Spout Circuit grounded
 
The other stud looking sensor with a wire boot on it.. on the drivers side? or the passenger side sensor.. It's a gt-40 intake so some sensors couldn't be used... at least one of them i do believe.
 
Definitely get the O2s hooked up so the computer can try to optimize the A/F ratio.

When you say that you have the MAP connected to a new vacuum line, does that mean that the car hasn't been converted to mass air? If it's still speed density you will never get it to run right with that E cam.
 
Definitely get the O2s hooked up so the computer can try to optimize the A/F ratio.

When you say that you have the MAP connected to a new vacuum line, does that mean that the car hasn't been converted to mass air? If it's still speed density you will never get it to run right with that E cam.

I have the stuff to swap for a maf but not enough time or patience currently.. and the car should still be able to hold its own with the cam either way .. before i pulled the lifters and replaced them I had a guy help me put the cam in prior to these issues.. he had my rockers set with lash and the thing still ran fine.. lol I know thats not right so .. new lifters.. preload on valves and the car has issue with running rich... I should also say the car ran okay without the o2s before too.. I do plan on having them installed soon though.( i know its a big part of the closed loop that the computer puts itself into and I will get them in very soon)
 
The other stud looking sensor with a wire boot on it.. on the drivers side? or the passenger side sensor.. It's a gt-40 intake so some sensors couldn't be used... at least one of them i do believe.
The temp sensor is located in the metal heater tube that runs down the passenger side of the engine, if you don't have the tubes then get a thermostat housing that has a threaded hole in the top and install it there.
The sender with the single post in the drivers side of the intake is for the temp gauge.
 
Definitely get the O2s hooked up so the computer can try to optimize the A/F ratio.

When you say that you have the MAP connected to a new vacuum line, does that mean that the car hasn't been converted to mass air? If it's still speed density you will never get it to run right with that E cam.
I've been very stubborn about not replacing it because part of it requires pulling the driver seat and tapping into more wire than i like to lol but I think I'm gonna take the advice and get on it and stop screwing around with the speed density junk.
 
The temp sensor is located in the metal heater tube that runs down the passenger side of the engine, if you don't have the tubes then get a thermostat housing that has a threaded hole in the top and install it there.
The sender with the single post in the drivers side of the intake is for the temp gauge.
Yeah I got that sensor there sorry I'm not looking at the car now had to think back .
 
ordering a new maf conversion harness from lmr and going to install that as soon as i get it and see if a maf computer i got doesn't handle this crap better like you're saying @Dan02gt 50 dollars to get rid of head aches then some more for o2s if i cant ever break my old ones free. lol
 
SD works well within the parameters it's tuned to.

The IAT sensor is supposed to be in the #5 runner on the drivers side. If the pad is not tapped for the sensor you have a few options.
#1 drill and tap for the sensor
#2 plug the sensor in and leave it laying on the intake next to the fuel rail
#3 put the IAT sensor in the air box and extend the wiring over to that location.

FYI the IAT information directly affects fuel trim and is used to adjust timing under high temp conditions. You need it hooked up
 
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SD works well within the parameters it's tuned to.

The IAT sensor is supposed to be in the #5 runner on the drivers side. If the pad is not tapped for the sensor you have a few options.
#1 drill and tap for the sensor
#2 plug the sensor in and leave it laying on the intake next to the fuel rail
#3 put the IAT sensor in the air box and extend the wiring over to that location.

FYI the IAT information directly affects fuel trim and is used to adjust timing under high temp conditions. You need it hooked up

and that would probably be the one left in my old intake that has no spot on the gt-40.. thank you again.