This would effect the idle wouldn't it? --- It idles perfectly.

Also, I did change the wires, but I changed them one at a time (Right after I changed that particular plug).


This is what I do know about the plugs --- On the front of the engine the plug furthest to the passenger side is 1 then 3 then 5. On the back furthest to the passenger side is 2 then 4 then 6.

Is this what you were looking for?

If you have a gas smell in the vacuum line to the FPR, it is leaking. Is it enough to cause your issue? Probably, but hard to say without being there personally.

You should'nt have ANY gas smell in that vacuum line.

My first bet at this point would be to have you replace the FPR. Even if it isn't causing your backfiring, this is a serious issue.

Replaced the FPR tonight. That thing has to be wiggled A LOT to get it out and it really gushed gas everywhere. Advanced Auto also just GAVE me a snap-ring tool (I think I found my new auto parts store).

Anyway, we took it out for a test run. There is a noticeable power difference. My dad even made a comment on it. It still sputters a little, but I figured I would give it some time on the chance that hopefully if any gas has pooled up anywhere that it will evaporate.


THANK YOU ---- I'll let you know if it is still sputtering in a couple of days.

It is possible that the PCM was compensating for the bad regulator. This may cause the PCM to need to relearn the duty cycle. You may want to disconnect the battery for 20 minutes and let it go back to default and relearn.

The repair manual said to disconnect the battery when I replaced the FPR (It was the first step).... So I did.

Geez..that darn manual is taking away all our GH secrets.

Do you have any way to scan the car?

Nope. I was contemplating buying a scantool.

Bah. It is still having issues. I took it to a mechanic and he "thinks" it is the supercharger. Very possible, but I'm weary of believing anything he said because he made the comment that "Superchargers don't whine".



Anyway, This is what I DO know:

I don't have any problems with the car in motion and the boost is 0 or below.

When I'm driving down the highway and the car is in 4th gear. --- Usually it is below 2K RPMs. If I hit the boost then, I can feel the car chug. It feels like I've just hit a large water puddle. It isn't constant. It seems to do it in short little spurts (If I keep on the gas, it keeps doing it though).

All gauges are reading normal readings.


I've observed. (That means this is prone to error) that the problem is more mild when it is colder. It was 20 degrees colder today and the boost was a lot more solid than yesterday. The problem also isn't as bad right after I've started the engine (It hasn't warmed up completely yet), than if I've been driving it for a couple of miles.


So far I've replaced Plugs, Wires, and the Fuel Pressure Regulator.


Is it time to get a scantool? Maybe call a mechanic that has a clue?

Did you ever clean up the battery cables, in particular pulling the boot off from the positive one?

I like your most recent description of the problem. For starters..the mechanic doesn't know much about superchargers and has zero idea about the problem. He'* guessing.

The supercharger isn't causing your problem.
What octane fuel are you running?
Do you hear any exhaust leaks?
Does it seems that your catalytic converter may be restricive and plugged up?

My first thoughts with your most recent post are that since it acts better with cooler weather you are experiencing massive knock retard. Knock retard removes timing anytime it believes predetonation is occurring.

Your year is very prone to exhaust manifold cracks, as a matter of fact..nearly every person that thinks they don't have them..has them. Recently a member used seafoam in his car and found his leaks by smoke pouring ouf of them from the seafoam.

Fuel octane will cause predetonation. Highest octane you can get is the only way to go.