cyl 2 misfire HELP ME!!

[touchvenus]

Okay, in the new adventures of my lovely lemon....

The SVS light came on, after my grand am was at the autobody place for 7 days, taking a vacation. I had it read at an auto parts store, and the code says that cyl #2 is misfiring. Having this problem before (with cyl 4), I figured it was just the spark plugs or wires.

So, I took my car home to my genius mechanic father and a whole slew of things were done to it, including: cleaning and measuring the spark plugs, checking for spark, cleaning the wires, testing the wires and plugs, and using some fuel injector cleaner. Nothing helped and Dad's out of ideas.

The symptoms are: shaking, especially when stopped or going at higher speeds (above 70), hesitation/sluggish on excelleration, idling at about 200rpm above normal and driving between 200 and 500 rmp above normal, running a little hot (nothing dangerous...just something I noticed), and....oddly....when I turn the fan on and off, I get weirdness. Turning it either on or off causes the rpms to raise anywhere from 300 to 500 above what it was running at. It stays at the raised level for about 10 seconds and then drops back down. And when I turn the fan off, there's a metallic clinking sound, like a marble rattling around in a tin can. I'm not sure if that's related, but I know it's a new thing.

Does anyone have any other suggestions of what to try to fix this problem?? Please please help me. Thanks a lot in advance!!!

[Bjornboy81]

Did he check the coil packs?

If it's running high idle then it could be a vaccum leak or a bad IAC (idle air control) valve.

I don't believe that it is running 200 - 500 rpms high during driving...that's impossible if it's an engine problem because your gear ratio is the same. If something is dragging (tranny or ebrake even) then I'd buy that, but I think you're mistaken.

I'm guessing a vaccum leak of some sort.

Good luck :)

[touchvenus]

I am not mistaken. I check the rpms very closely all the time, cause I'm paranoid. Generally, at 80 mph, it runs at about 2500 rpm. Now, with it broken, it runs at about 2800 to 3000 rpm. That's high. At 45 mph, it normally runs around 1400 rpm; it currently runs between 1500 and 1700 rpm. That's also high. And no, nothing drags.

Thanks for the advice about the vacuum and the coil packs. I'll have that checked out.

^.^

[coupe]

Well the tin can sound i can tell ya right now that the A/C clutch is toasted. Sound goes away when you turn on your A/C, definately A/C clutch, pretty common.

Your injectors could be crapping out on you or like Paul said you have a IAT that needs cleaning or you have a vaccum leak.

[rixGAphx]

Hokay, let's back-up a little.

WHY was the car in the body shop??

When you got the car from there, did it have the current symptoms:
"...shaking, especially when stopped or going at higher speeds (above 70), hesitation/sluggish on excelleration, idling at about 200rpm above normal and driving between 200 and 500 rmp above normal, running a little hot..."?

You say the SVS light was 'on', so you had the code read.
Your car has TWO 'Service' lights:
SVS = Service Vehicle Soon = Body Control Module; for lighting, power windows, power locks, I *think* also for AC.
SES = Service Engine Soon = Powertrain Control Module, for the engine, tranny, and emissions (including gas cap).

Are you sure it was an SVS code? or perhaps it was the SES?
THIS IS VERY IMPORTANT!!

The parts store scan tools generally canNOT read an SVS code; only SES codes.

So, you had an SVS light 'on' but you still don't know what set that.
He just gave you the stored code for P0302 Misfire detected #2 cylinder (which could have been an old code from last week).

Even if you had a DEAD #2 spark plug, I doubt you'd get the symptoms that you describe.
* * *

Your engine cannot 'run at higher rpms' at the same speeds as before, except in "fourth" gear.
This actually 3rd gear with an electrically-operated solenoid/clutch that bypasses the torque converter and acts like a 4th/'overdrive' gear.
The only other way a car with an automatic tranny can 'run at higher rpms' in the same gear/at same speed is if the tranny is very messed-up inside, with the torque converter slipping, clutches and bands slipping, and the thing generally very low on fluid and/or about to finally crap-out.
* * *

Finally, the AC clutch is also electrically-operated, and the the engine's idle rpm is automatically increased whenever the AC comes 'on' to prevent stalling of the engine.

All in all, yeah, vacuum is a possible source of the problem.

But as with nearly everything on a GA, there is a strong electrical component of these systems.

You should definitely check the battery, the alternator, and especially the battery cables (both ends of both cables).
Even without the 'Battery light' not being 'on', your car can be in a world of hurt for strong electrical power.
This causes trouble with the tranny and the AC, and can also cause the ABS light to come 'on'.
* * *

Plug #2 is paired on the same coil with plug 5.
If the coil were the cause of the #2 misfire, then you would also get a #5 misfire code.
Misfires can be cause also by the fuel injectors, running too lean or running so rich that they actually leak gasoline full-time into the intake mainifold.

Hope this helps.
-Rick

PS:
Yeah, I think half of all GA problems stem directly from bad battery cables.
SO??
Anybody wanna prove me wrong?? :dukesup: :D :D

[touchvenus]

Okay, my car was in the shop cause I got side-swiped on the freeway, and there was a little body damage. The symptoms I described did NOT come on until after I picked the car up, after the bodywork was complete.

Sorry! I meant the SES! I thought I double-checked that.....the SVS light IS also on, but that's cause of the wheel bearing being broken, again. I had the SES code read at the auto parts store (and cleared....twice). I also had it read three or four different times while my dad was working on it (after disconnecting the battery and whatnot).

As for the AC thing....I haven't even used my AC in a year. I wasn't turning the AC on and off, just the vent fan. It could be the same problem though, for all I know.

The battery and all would have been a good idea, but when my car randomly wouldn't start last week, all of that was checked, to make sure it wasn't causeing THAT particular problem. It seems fine.

.....I about ready to set this car on fire....

Thank you so much for all your help! I really really appreciate it!!