help with diagnosis

Ericdd · 10-31-2004, 02:31 PM

My car is running super rich, and stalling at lights and stop signs. I brought it to my mechanic and the only codes it was showing was random misfire. I changed the cap and rotor and it didn't change anything. The plugs are relatively new and so are the wires. It seams to run fine at any speed, but when I let of the gas it back fires and gurgles. My egts at idle used to be 800ish but now they are down around 600ish. Fuel pressure seams normal as well. The code machine was getting no reading from the rear O2 sensor, but I don't see how that would do much. The manifold pressure sensor had no readings either. Both of those were disconnected when I had the 95 ecu in anyway, so I don't see how they could cause this.

Any help would be great

totaled200ser · 11-01-2004, 02:49 PM

how did the cap & rotor look? check to see if the o2 is slow, did you ever do wires? how bout the plugs, what are they gapped at? do you have and exhaust leak at all?

Ericdd · 11-01-2004, 07:25 PM

Quote:

Originally Posted by totaled200ser

how did the cap & rotor look? check to see if the o2 is slow, did you ever do wires? how bout the plugs, what are they gapped at? do you have and exhaust leak at all?

the rotor and cap looked a little corroded. the wires and plugs were both fairly new. I have a small header leak, but I've had it for months, everything else is good

totaled200ser · 11-03-2004, 12:00 PM

i'm wondering if you header leak is effecting your o2 readings, where is the leak? get the car hooked up to a scanner and check all the readings, if you don't get anything abnormal from that you need to hook it up to a scope and see when it is getting this random misfire

Ericdd · 11-03-2004, 07:27 PM

the leaky header was the same since 4-5 months ago, so I don't think it is that. the leak is at the 4-1 collector. I gave the car to the body shop to fix a dent and he's giving it to his affiliated mechanic to check out. This way I have access to a free rent-a-car while it gets worked on for both. maybe the car is angry about the dent or something (I know I am)

PrototypeSMX · 11-04-2004, 11:38 PM

Whats your TPS readings?? If thats gone then that could explain the rich mixtures.

goneturbo · 11-05-2004, 10:49 PM

take out the plugs and see what they look like. If every single one is black then you are running rich in every cylinder and you can rule out an injector problem, but if any of the plugs look like they are in good shape then you have a different problem. report back on your findings.

Ericdd · 11-05-2004, 11:10 PM

The car is in the body shop now getting a dent fixed, they are gonna give it to a mechanic to fix for me. if they don't fix it then I'll check all that.
thanks

goneturbo · 11-06-2004, 12:50 PM

That sounds like a good way to waste your money. Hope they find it on the first shot.

Ericdd · 11-06-2004, 02:47 PM

yeah well time is money and I don't have time now. But I do have a rent a car Paid for by the insurance company of the person that hit me.