Hello, first let me describe the issue, and then I will go on to what has been done.

At the moment, the car starts instantly, and idles decently until you apply the brakes or go into gear. Before the engine gets warm, the car revs normal but has a rough idle when you come to a stop or are stopped in gear. Shifting to park sort of alleviates the issue. I noticed tonight, that applying the brakes causes the idle to go down to ~500 rpm or so, and when you let go of the brakes, it jumps for 1000 for a second and back around 600-800. The exhaust through everything I have tried, and still is happening, to the best I could describe it is "puhpuhpuhpuhpuhpuhpuhpuhpuhpuh" Seriously though, how do you describe that?.

The problem was way worse at first. Couldn't barely accelerate, the car would stutter like crazy, and stall when stopped and in gear.

First I changed the spark plugs and wires. No difference, spark plug 2 was burned to @!#$ and sooty.
Then came the ignition coils, because they both had giant cracks in them.
Same problem persisted, so we read some other posts and some youtube videos and checked out the (The name is lost on me right now, the valve right before the injectors) and it seemed to be functioning how it should, not pumping gas out. Then we pulled the fuel rail. Injector on the second cylinder was a high pressure stream instead of a pulse. So we changed that stuck open injector, thought the problem was solved but it was not. Changed out the second spark plug thinking it was fouled again from all that extra gas. It was but it didnt change anything.
Earlier this week, I changed both oxygen sensors. This seemed to make the car more stable, and how it is right now. However the idle did not change and once the cars warm it's hesitating again.
Tonight, I was spraying carb cleaner on whatever vacuum lines I could find. I don't really know where they all are however. Nothing struck me as vacuum leak. Now I watched a video about the brake booster being a problem, because when I press the brakes it changes the idle to low as I mentioned earlier. I pulled the hose and check valve from the booster and the car revved high for a second and back to puttering. I really can't tell if this did anything. when I kept the hose plugged with my thumb, the car stalled out.

The only thing I did not do to this point was clean the throttle body and change the air filter. Previous owner has a cone filter on there so I'd have to order one.

Any other ideas to try?

Id check the throttle position sensor


ReD RaiN

Let a friend borrow my multimeter and haven't seen it since. So.. ordered a new TPS and a new cone air filter.
Had the CEL reset today and it ran smooth through all the gears except when idle. Had the p0300 and p0147 codes. Is it possible the o2 sensors don't work correctly after replaced if the codes aren't cleared?

The TPS was changed, along with the air filter. Still have a stutter, and the check engine light, but idle is more stable now. I'm wondering if that spark plug is fouled again. Only one way to find out. Don't know what else to even try.

I would try the idle air control. It will cause a lot of low rpm problems. I would also say egr but your2.2 shouldn't have a egr. Other then that if you have proper spark on all cylinders and fuel pressure is in its proper range not sure. Are there any engine codes you can pull from obd2. O and the part you weren't sure about name sounds like fuel pressure regulator.

I got the codes read on monday again,was a bunch of P0300 stored in memory. I don't know if they were just built up or what. Seems like the car is in a limp mode right now.
I will look at the idle air control.

- Faulty spark plug
- Faulty ignition coil
- Clogged or faulty fuel injector
- Intake air leak
- Fuel injectors harness is open or shorted
- Fuel Injectors circuit poor electrical connection
- Ignition coils harness is open or shorted
- Ignition coils circuit poor electrical connection
- Insufficient cylinders compression
- Incorrect fuel pressure. Intake air leak is common cause according to sit I pulled this info from.