[msea85]

I replaced the injectors and the car was running fantastically. Then occasionally it would spit and sputter on acceleration, but would go away. Now I can not accelerate without it bogging down. Went through and replaced TPS, Coolant sensor, MAF with no help to symptoms. The check engine light stopped working on me, I have replaced a burned out light bulb. but now there is no voltage to the check engine light circuit. All other lights on the information console work. I have read back on some posts that make suggestions of possible ECM failure.

One other thing to mention is it will start and Idle but when it hits closed loop I hear air coming from air intake and catylitic converter.

Possible Diverter valve problems??

Help

Thanks in advance

 

[driley]

Trust me, FUEL PUMP! Replace the fuel pump and fuel pump relay. The relay is located on the front drivers side fender well next to the battery. The fuel pump is easy to change and can be done from the top and without dropping the tank. With instructions from a manual, should just take a couple hours. I've already been through this senario with my 85. Alse look at the wires on the relay, because the insulation could be deteriorated. I ended up having to get a replacement plug for mine.

 

[msea85]

I have done all that as well. i guess i could pull the fuel pump out and make sure that nothing came loose on the wire connections. I have not officially done the relay but it looks like it has been redone. New relay and wiring coming out from the bottom of the relay.

 

[Kod_X]

I have done all that as well. i guess i could pull the fuel pump out and make sure that nothing came loose on the wire connections. I have not officially done the relay but it looks like it has been redone. New relay and wiring coming out from the bottom of the relay.

Checked your plug wires for cracks or frays?

 

[msea85]

those are all approximately 4-5 months old. wires, cap, the works

 

[Patrick]

clogged catalytic converters. your car idles fine, but then it chokes when you really need flow.

 

[msea85]

Thanks for all the helpful input. That crossed my mind as well. Any one know a way of testing for this?

 

[redimpss5]

I go with Patrick on this one.

 

[driley]

Does the fuel pump energize when you turn the key without starting it? You should hear it run for a second. If your converters are stopped up, it would smell like rotten eggs or sulfer when it has been running. Also the converter will start glowing red if run for a long time if it is clogged. Not good in a car with fiberglass floor boards.

 

[Patrick]

Thanks for all the helpful input. That crossed my mind as well. Any one know a way of testing for this?

You can flow test the exhaust... but since you have to take it off anyway, just replace the cats while you are at it with aftermarket ones. Won't be too expensive, and I guarantee right now there is SOME restriction in the cats. You will feel more HP... everyone does after replacing the cats on early C4s.

:thumbsup:

 

[msea85]

Thanks guys, I will replace the cat. I checked the fuel pump and it is enganging and priming with the turn of the key. One more question though, do you all have any idea why my check engine light will not work? what could potentially cause this?

 

[The Shield]

One more question though, do you all have any idea why my check engine light will not work? what could potentially cause this?

The bulb could be burnt out, bad connection at the socket, or problem with the ECM. How do you know it's not working?

 

[msea85]

it does not come on with intial key turn on. I have replaced the bulb which was burnt out, but know still does not work. I have checked for voltage at the socket and all the way back to the connection to the center console. I have not gone back as fara as the connection from the speed/tach cluster.