My 05 grand am 3.4 V6, out of the blue started having idling problems,it started from 500-1500 rpm surges for a few seconds then stalls. It will restart, but it may do the same thing or idle fine like
The car will surge at idle from,500-1500rpms then stall. It will restart sometimes with the same problem and other
times not. The surges will last for 5-10 seconds. It drives on the highway fine, but you don't know what to expect
when you slow down. Fuel pressure is normal, I have blocked off the EGR valve with no change, changed IAC valve
with no change. Spark plugs look like they are in a lean burn situation after this happens. The ignition switch was
replaced six months ago. Engine code says multiple cylinder misfires. Please help, maybe the TPS next?
Vacuum leak next. What is your manifold vacuum?
Fuel pressure may be normal but it sounds like fuel pump may be begining to fail
Go to GAOwnersClub.com and search their threads before replacing any more parts. I would agree with John about a vacuum leak. GAOC can point you to the areas to look. I have the 2.2L Ecotec but I have seen your problem addressed.
A bad fuel pump typically shows worse symptoms with higher rpms due to its inability to keep up with the higher fuel demands. This is the opposite, I would say a bad fuel pressure regulator before I said the pump.
Thanks for your help guys. I hooked up the scanner and had my son drive the car while I watched the data. Part of the problem was a failing coil pack, I replaced it and the plugs and it fixed majority of the problem. The car no longer surges at idle but it still starts hard when cold. I agree that fuel pump is going to fail soon. If I hold the gas pedal about half way down when I crank it on a cold start it will fire right up and run fine after that. If I don't hold the pedal half way it may or may not start and sets a check engine light. ( multiple cylinder misfires). Vacuum is fine and fuel pump hold 60 lbs just turning the key on, but on cold start the fuel system drains itself and I have to hit the key 4-5 times to get the pressure up. It starts and runs fine after warm up. Again thanks for the help, it's very appreciated. Thanks Jeff
I had a simular thing happen 99 suburban. My fuel pump went out, i new it was going bad, had been for a year, once in a while i would have to take my hammer and beat the bottom of the fuel tank to get it to pump. Well 101 vehicle maitenance (beat on it with something) stopped working, so i changed it 301.00 dollar fuel pump. I drove to colorado, about 9 hundred miles from me, no problen pulling a big 18 foot tandem axle trailer. Picked up my daughters car and started back. Had all kinds of issues lean codes like crazy, didnt think i was going to make it home. Tried different on the road fixes nothing. Ran like shit, limped it in, made it home. For a month after that. I fealt with having to turn key on and off several times to get it to start. Surley it couldnt be the new fuel pump, so im looking at everything else that can cause these issues, finely, i decide this fuel pump has to br junk, sometimes it would fire up no prob, but othet times it was a bitch, it was very sluggish going down the road if u tried to accelerate to fast it would fall on its face. Took month old pump back to where i got it, they warrentied it for me. Put it in all my problems went a way. So thsts why i think ur pump is faulty.
iuf change pump do not forhet to change tge filter as well, too many fuel pumps are overworked with clogged fuel filters....
Yes, good point, fuel filter a must
CAN I DIVE MY CAR IF IT HAS A AC FUEL PRESSURE LEEK
Is it leaking fuel or refrigerant?
I had the same problem and found that I installed the wrong air intake gasket. If you had work on it recently I would replace the gasket. some models have a gasket that block some flow . Mine was open but the gasket I installed had blocked some airflow.
We had Surging problems - Found the Spark Plugs were Gas Fouled - Replaced Plugs - Replaced Oil and the Fuel Pressure regulator was leaking and we replaced that and still had surging problems. Finally found the EGR (exhaust gas Re-circulation Valve was bad. Fixed the problem. We also replaced the Fuel Filter & did a Motor Vac. Car Runs Beautifully. Four Seasons Auto Centers, Vancouver WA (360) 449-0069
bad idle position sensor to me sounds like.i had same issue with 2004 grand am gt V6 and it was the idle position sensor and after i changed it and scanned the computer for codes and cleared the idle position sensor code it ran top notch no more idle up and down
Clean your throttle body and throttle plate.
I pulled the pcv valve out of the valve cover and the idle returned to normal, if the pcv valve is plugged or or ventilation is blocked, this seemed to affect the idle causing surging and idle stalls after engine warm up. Still searching for the vacuum blockage.
Looks like the EVAP Canister Purge Valve is the likely problem on my stalling vacuum issue, I traced the line back to the purge valve and noticed it was rapid pulsing and would kill the engine when reconnecting the small vacuum feed line. Idles perfect when disconnected. Waiting for the part come in to see if it is the fix....2000 Grand Am GT 3.4 V6
I have the 03 3.4 was having a similar problem. The middle coil kept failing. After I took the coils off and replaced them twice I went to the ICM (ignition control switch) and found it was cracked. Shorting out that coil. Put a new one on it and now its running off all cylinders. On a cold start it starts fine but other times its hard to start and I have to use the gas pedal to get it to run. Also im having idling problems now.
Purge valve replacement didn't help, tried a new fuel pressure regulator, put new O2 sensor in too and a new temp sensor while I was at it... still wont idle. I can get it to high idle only by unhooking the idle control solenoid and stting the idle air plunger manually and leaving it electrically unhooked. I'm thinking a new flashed PCM may be my last option....2000 grand am gt 3.4 v6 ,174,000 miles had her for 11 yrs.
My 2000 Grand Am 3.4 is having similar issues with a surging idle but mine isn't dying out just surging at idle. Any acceleration at all is smooth, drive 100 mph just fine but when i come to a stop the idle surges. Mass air flow sensor checked, EGR valve checked, throttle body cleaned and checked, another valve for the idle (can't remember the name of)...checked. Nothing seems to be wrong with this thing but the surge continues! Need help!!!
I had a 04 that had similar issues.i replaced both o2 sensors and the idle control sensor on the throttle body and it solved the issue.make sure you replace both o2 sensors. one on the exhaust manifold and one under the car by the cat. converter on the exhaust.
check the MAF, turn off, unplug wiring, restart and if the vehicle is running smoothly new MAF sensor time
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