Title says it all...

My car was running like crap a few weeks ago, naturally I started with the plugs and found out that they were fouled pretty bad. Those plugs were about two years old on a cammed and untuned motor.

Fastforward to yesterday. I finally got my new plugs in and the car ran so freaking great! It ran for less than ten minutes total in my driveway (No tags/Insurance/slipping 4L60E FTL!!)

I went out to the car today to start it up to move it out of the garage so I could clean up and to my suprise the car was running like crap again. I would rev it in neutral and it would not want to rev very high. It also felt shaky and I heard a weird sucking noise too...I pulled a plug and it looks like this.


It's freaking fouled out already and it smells like gas!!!!!...What could cause this to happen??? Any input would greatly be appreciated, Merry Christmas!

Drew

(Car has hotcam, 1.6rr's, longtubes, offroad y-pipe, and some other things that I can't remember)

 

Might be a good idea to expand on the details, beyond "running like crap". What are the EXACT symptoms? How does it start? How does it run/idle for the first three minutes or so? Does the problem seem to get worse after a few minutes, when the PCM would typically go into closed loop? Does it bog, misfire, at what speeds and under what throttle position?

 

It seems to start up ok. It will idle around 1100 rpm for a few seconds before it drops down to around 700rpms. The check engine light will come on(no egr or AIR, it has been on for a few years now) and it will stutter whenever the gas is touched. If you try to give it any decent amount of gas the whole car will shake and stutter up to 3500 rpm. I shut her down after that. It also seems to idle alot more lopey than what it normally does. It sounds like it has a cam that is much much larger than my hotcam.

I can't get out and drive the car so I can't tell you the speeds that it bogs, but I can tell you that it bogs under no load at idle. And it does get a bit worse as it warms up.

 

fuel pressure reg?

 

Sounds like the PCM is seeing a "false" lean condition, and adding fuel the engine doesn't need. Do you have any severe exhaust leaks before the O2 sensors? How old are the O2 sensors? What brand? What kind of extensions did you use.... homemade? Have you checked the inlet elbow/bellows for tears, or being folded under at the bottom of the throttle body? Is the "lope" really a lot of misfires? Misfires cause it to run rich, and running rich makes it misfire more.... just keeps getting worse.

When it started running poorly a couple weeks ago, had you made any changes or done any mods immediately before that? Or was it a gradual deterioration of performance over a longer period of time?

I would get it scanned. You are assuming its just the EGR and AIR deletion. AIR deletion will not cause an SES light, if you insure there is a good fuse in the circuit after you pull the connector off the AIR pump. You can eliminate the SES light for the missing EGR vacuum solenoid with a simple resistor. The SES light for the missing EGR valve is fairly unusual in the OBD-I cars. If you have all these problems, it would be a good idea to have it tuned - first to account for the LT4 HOT cam, and second to deleted the codes for the missing emissions systems. But it may be something else causing the SES light, but you won't know that without a scan.

 

The 02's are about two years old and from autozone. The extentions were purchased from Thunder Racing, I do not know the brand but they are well made. I just checked the intake elbow and it is on fine with no tears. When it idles it seems fine, just that it is a lower idle than normal while in park. When I give it gas I can feel it miss. Maybe it is missing at idle, all I can tell is that is at a lower rpm.

It is funny becuase none of this was a problem when I drove it on a daily basis. Only since it has been sitting since September has it got worse.

I will go get a scan tool and see what it says. When I get the new tranny(mid february) I will definatly take it to go get tuned.

Thank you so much for the help!

 

Needs TLC.

 

TLC...Beauty is only skin deep ;-)

 

Get rid of those Autozone sensors and replace them with GM/Delco 02 sensors. If you use anything but GM/Delco sensors on your car, you are askin for trouble.



Nick