Hello, New member from Florida. I have a 2000 MC ss with 90,000 miles. Car ran perfect upto a month ago. Since then there is aproblem that cannot be diagnosed by the mechanic who has worked on it. Car stalls or completely dies at low speeds (30-35 mph) or stopped at traffic lites. Also, it stutters sometimes while driving at 45mph. The last thing is that sometimes it just won't start until 4 or 5 tries. Runs great at highway speeds (65-70mph). Here is what has been done after 10 trips to the mechanic. Replace fuel pump, fuel filter,map sensor, cleared out all codes and many other things that I can't remember. Problem is intermittent. Check engine lite only came once. I trust the mechanic but I desperately need help. I am totally ignorant about fixing car problems but I reall want to fix this car because this is my second Monte and I relly like them. Please help. Thank you yo all who answer.

 

Welcome!

Do you recall if the Idle Air Control valve was serviced? Carbon build up on it can cause stalling. Surging at certain speeds can be caused by a variety of things. Dirty injectors, dirty M*** Air Flow sensor, vacuum leak, etc. can all cause this. Do you know what the codes are that were cleared?

 

Hi Albatross & Welcome to the Monte Carlo Family.

Sorry to read about your problems. I hope one of our member's can give you some advice or solutions to your problems...It's difficult to diagnose a problem with just words, and I hope that one of our experts knows of a same a similar type problem & can help.

Are you the original owner ?

Is your mechanic a GM Tech ? Have you searched for another Chevy Mechanic in your area ?

Wish you Good Luck on finding a solution to your problem
p.s. I hope you don't get hit by the storms coming in around your area

 

Thank you for all the input. Don't know the codes that were cleared. Don't know that much about these newer cars with computers. I'm 65 and just remember points and plugs. Car just dies with no warning but only at stop lights and slow speeds. Sometimes it takes 5 or 6 tries to re-start. Also when it won't start it bucks and shutters like it is not getting enough gas. sometimes if you pump the accelerator it will catch and start. I also get a sttuter when driving at 40-45mph. These problems only happen sporadically so there is no consistency for these things happening. It has gotten to where I am afraid to drive this car because I feel it is unsafe.

 

sounds like TPS (IAC) (remove it and clean or replace it)......also i would either clean or replace the ..mass air flow sensor....

 

Welcome to the MCF. What part of Florida are you from?

 

I would say Mass airflow sensor. If you ran a K&N filter they have a oil film on the filter this can gum up a throttle body and the mafs. Alot of people run them with no probs but my 94 lumina had same issues and it was throttlebody being gummed up and Mafs being gummed up from K&N filter. swapped all 3 and put a stock filter in and fixed the prob.

 

You need to get us the actual engine code the car is producing. That probably holds the answer (the car's onboard computer is telling you what is the problem).

I just helped a friend's dad with his '02 Bonneville running a 3800 with symptoms much like you described. His code was P0102 if I recall (Mass Air Flow Sensor or MAF). We tried cleaning the MAF and unfortunately, it did not work for this one. We have a replacement on order. If it is in fact the MAF, you can disconnect the MAF and the engine should appear to run fine. This is NOT a fix (as now the computer is missing data to properly run the car, so it's substituting data with generic values). But it will help pin-point the problem.
But again, get us the actual code. The description of the symptoms and what has been done sounds like your mechanic just cleared the codes for the heck of it and never actually investigated what they were and took shots in the dark.

 

agree with this 100%

welcome to mcf! hope it gets fixed for you soon!