Please see my thread at LS1.com

click me

If you don't have a registered name there, post here and I will check as well. This problem is really starting to annoy me. Thanks

Brad

 

Come on guys...There was a 20+ page thread on this. Did anybody find out something new or definite on why our cars do this?

 

I have a low RPM stumble and my EGR valve is sticking opened.

 

I started the car and then went to try and push in on the diaphram of the EGR. It moved a little but not much and the car didn't act like it wanted to die and the rpm didn't decrease. Does this mean the thing is stuck open and causing my problems? thanks

 

i had the lower rpm stumble and it had a surging idle at stop signs only when warmed up, and I replaced the water pump and the opti and all is gone and has been for a week, it runs like it used to, and it has 115,000 on it...maybe you could try this but I would hook a computer up to it first and see if you get codes, cause Opti Code was coming up when i replaced mine.

Hope you figure out your problem...

 

i had the same problem last year, wound up beeing the wires even if theyre new, they could be broken somehow internally (Like mine, cause of me), so i wouldnt rule those out just yet hth

 

I had a low rpm stumble and it would surge when I was stopped. It would get worse the longer I ran the car. I changed the EGR, fuel filter, coil and coil module, checked for vacuum leaks. Plugs and wires were pretty new, every thing helped some but did not cure it. Finally changed the Opti and water pump, problem gone.
Good luck.

 

Thanks for the replies fellas. I may look into doing the coil and wires and then the opti if that doesn't cure it

 

I got it scanned today and the tech said the 8 cyclinder was out and it was the plug wire. I changed the plug wire and had the problem didn't go away

 

Did you check for any tears on your intake elbow where it connects to the throttle body?

 

its the map sensor

 

yeah, i've checked the intake elbow and it's fine.

what makes you sure it's the map sensor when the scan showed there was no fire getting to the 8 cyclinder?

 

TTT

 

I had the same problem an it turned out to be the fuel pump. But ofcourse the tech initially suspected opti, plugs, wires ...etc

 

its raised gas mileage about 2 miles per gallon and got my lower rpms smoother