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Hello, I started experiencing a problem with my 2002 Grand Am today. 3.4L V6
When I got to work this morning and parked I could hear a whistling sound, turned off the heat and music and the whistling was coming from the front end of my car. I turned off the ignition and it sounded like a balloon deflating. Did not think anything of it. On my lunch break, I drove it to a nearby store and I found that when stopped at a red light the car seemed to be idling rough and rocking back and forth. No lights lit up, so I thought maybe it will be fine when I return to work. When I got back in, I noticed it is still rocking when idling. I was scared to drive it so I called a mechanic I use all the time, he didn`t think it was too much to worry about and told me to go ahead and take it home. When I drove home, it was fine for a few minutes but started the rocking again when warmed up. My check engine light then came on. I started watching the RPM when I would stop at red lights. My RPM while driving is about 2000-2500. When I stop, it suddenly drops from 1000-500. Then starts going up and down between 500-900. I refuse to drive it now, as I don`t want to make this worse. It has been harder on gas for a little while, but I thought maybe it was just an old car thing. Any advice would be extremely helpful.
Thank you.
Josee
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Replies
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could be a vacuum leak. sounds like the car is misfiring.
also have the code read at an auto part store for free and
post codes.Ok, So I had codes read today.
Mass Airflow Sensor Circuit A P0101
O2 Sensor Circuit low voltage P0131
System 2 Lean P0171
Random Multiple Misfire P0300Fuel rail pressure optimal
Short term fuel lean 3.8%
Timing advance at cylinder 1: 17 degrees
02 sensors: bank one sensor 1 26.6%02 sensors: bank one sensor 2 99.6%
All intake pressures are within normal range no leaks in manifold
Rest throttle position: .17cm (no percentage reading
Vehicle idle load 2%
This is what I got from the reading… Any help interpreting??
Thanks
clean the MAF. Replace the fuel filter I would read
fuel pressure before and after the fuel filter change.
The pressure should be 52-60 psi with key on engine off
and not drop more than 5-10 psi when off.http://easyautodiagnostics.com/gm_maf_testing/test_maf_gm_1.php
Yeah very common issue these days with every car. I have had to replace more freaking fuel filters then I can count. People complain there car is doing weird things, idle rough, dieing at idle, low power, bad vibrations… Here is the reason, the fuel we are using today is horrid, its so dang filthy and watered down that the fuel filters now just are not able to cope as long as they use to. I recently just replaced a fuel filter on a rig that I did the very same job on a month ago. The filter looked like it was a stock filter that had been in there for decades…could not believe it!!
I referenced problems on my 2001 Grand Am on this forum within the last month or so. One was RPM fluctuation between 500 and 1500 during idle only. (Had been doing that for a while). Finally began to be hard to start; I suspected fuel pump (which is inside the tank) but replaced the fuel filter first (it’s underneath the car at the fuel tank). RPM’s work fine now but still seems to be running rich with slight gas smell and not so good gas mileage. Still working on that. The fuel in the old filter was like black water and like “UncleJohn” said, the fuel quality today seems horrible almost no matter where you buy it. I used to be bad to let my fuel stay around 1/4 tank until this happened but I know now how that can be hard on the car, fuel pump, filter, etc. As far as the “whistling” sound and the balloon deflating sound and rocking back and forth, that sounds like something different. Also a Mass Air Flow sensor (MAF) can make it run roughly and give bad gas mileage as well (it helps regulate air/fuel). It’s located right beside the throttle (where the big air hose connects to the side of the top of the engine) and has a small vacuum hose going into the top of it. You could take the vacuum hose off it, while running, and leave it off for a couple minutes or so. If you start getting any fuel coming out of the top of the MAF, it probably needs replaced since that shouldn’t happen. Just a couple ideas to start with. By the way, I never had any check engine lights during any of this on my car.
Edit: I should have added that the “rocking” could in fact be related to the rough idle I would think. That and misfiring could be related to screwed up amounts of fuel and air getting into the engine in just the right mixture (vacuum hoses can be related that). I have learned engines are pretty particular about those things and fairly small anomalies can make for some rough running. Keep up informed!
2nd EDIT!! The picture I show here and the description I gave is actually the FUEL PRESSURE REGULATOR and NOT the MAF Sensor!! Sorry, I labeled it wrong in the pic! But the FPR can still be bad and it’s good to check it. Sorry for the mislabeling. Not sure where my mind was at the time 👿
Related to UncleJohn’s bad gas comments; this is just my opinion but I think the ethanol, i.e., alcohol, in much of our gas today is way too hard on some engines, at least I am quickly coming to that opinion in my own personal experience. I don’t know the scientific facts on that or anything but just seems my particular car/engine doesn’t want to perform well with all that ethanol in it.
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