PontiacBonnevilleClub.com

I'll try to make this as short as possible: so Bonnie is having sputtering and power loss issues starting last Saturday, when I was on the Highway. I was out doing some driving and she was perfect no issues whatsoever. I hopped on the highway and suddenly when I get up to speed the power starts to cut out (around 2500-3000rpm) and the tachometer is shooting all over the place along with jerking and hesitation accompanied with light backfire. Fortunately, I was able to pull over and the engine shut itself off. I couldn't get her re started and had to get her towed home. The check engine light only shows intermittently, so I had to catch the pending codes: which were p0300. So far i've changed the spark plugs and wires, air filter, battery, and today the fuel filter. There was improvement after changing the fuel filter but a few hours later she is doing the same thing. I start her, she runs roughly - then shuts off. I try to start again and it won't crank. She runs fine when its cold but the problems seem to worsen when she's warm. A couple of weeks back I had the fuel pump changed. I know I should've replaced the filter at the same time, which is leading me to believe I may have clogged the injectors in the process. I've done the "screwdriver test" and all of them are clicking, but i'm not sure if that means they aren't clogged. Do you all suggest getting them cleaned or can it be another issue?

The backfiring seems to point to timing. Could it be crankshaft position sensor or camshaft position sensor? I have never had this situation so I am not sure.

Get a scantool that can read live data and then watch the misfires to see which cylinder(s) is your culprit. That will eliminate a lot of diagnosing. Once you figure out what cylinder, pull the spark plug wire off the coil to see if its getting spark. If you have spark there and you have new plugs and wires, that points you to fuel. You could try swapping injectors around to see if you can get the misfire to switch cylinders.

I'll definitely look into doing that tomorrow morning, anyone know how to remove injectors?

Bleed off any fuel pressure at the schrader valve. Remove the 4-10mm nuts that hold the fuel rail down and then pry it up. You can leave the fuel lines connected. Release the clips and then wiggle/pull out the injectors.

Ok, thanks. I had the injectors cleaned today, she worked great for longer than usual but later in the afternoon while sitting in idle, it started to jerk and cut off again. It came back on for a few seconds while in neutral but eventually died out again. I waited a few minutes and got it startef, and drive home but it was definitely missing as I felt the jerking when revving past 1500. Can it be the fuel regulator?

New update guys, please watch video.. the bottom right belt pulley is intermittent https://youtu.be/m41S53FCpsg

that's the A/C compressor disengaging

Is that good? Also, can the icm be under performing though the coils are generating current to each other. I didn't have a multimeter so, I tested by removing the plugs wires and watching for a spark between the coils, which was present in all 3 coils.

harofreak00 gave you the best advice. If you do not want to follow that I suggest you have a mechanic look at the car.

We'll the misfire code is gone, and I don't think it would be a fuel issue. I changed my fuel pump and filter about 3 weeks ago. Also, the FPR isn't leaking nor did it smell like fuel when I did the "rub test" and my injectors were cleaned maybe a couple of months ago. I still get the P0350 and P1350, but only when the car is warm. But if the ICM is going bad, wouldn't the coils not transfer voltage?

Have you tried unplugging the mass air flow sensor? Start it up and see what happens.