Could use suggestions....

**Mike8410** · 12-20-2010

My Grand Prix GT has been acting up recently. It is getting extremely horrible gas milage, I figured it to be about 8 MPG in town! i have changed the air filter, spark plugs, fuel relay, and a coil pack. next on my list is fuel filter and plug wires. Now when I did the plugs i pulled out autolite double plantinums(i was so pissed seeing cheap crap plugs in it) and replaced them with E3's. Replacing the air filter i found the one in it to be bent, with a few pleets bent up and part of the gasket on the edge gone! I also cleaned the throttle body and added some fuel cleaner(Sea Foam) to a full tank of gas. Ok so it helped a little bit, I am getting about 12 MPG now, but my car is still Idling very strangely. It will idle at about 900 but loses RMS and the engine revs back up my itself. There are also times where I am stopped and the car will rev up and try to take off by itself. I'm thinking it may be the throttle control sensor, but could also have to do with the fact the plug wires on it now are crappy autolites. any suggestions on which step i should take next to get my car to where it should be running and idling properly? Thank you in advance.

**01gpgt01** · 12-20-2010

Alot of people Esp moded run Autolites FWIW I run Autolite 103's. Anyways do you have any codes?

**Mike8410** · 12-20-2010

thats what is making this more difficult, there are no code's popping up at all.
This is what is really annoying about the whole situation, I'm just glad i work at a parts store so im not payin out the ass for parts.

**blueguy** · 12-20-2010

E3's are cheap crap ass plugs too...that you end up paying out the ass for. The 3800 is old school...and it likes old school plugs...as in, Autolite 606's. Copper Core...cheap and effective. Done.

As for your MPG's...I'd bet its the o2 in the rear manifold or a dry rotted vacuum line causing a leak...check that. That'll give you craptastic MPG's since it is throwing your fuel trims all out of whack.

**Mike8410** · 12-20-2010

I have went through and checked all the vaccuum lines. I'll add the rear o2 sensor to my list. ty

**Fivefingerdeathpunch** · 12-20-2010

no,

change the front o2 sensor, right after the rear manifold.

the rear o2 is behind the cat.

**shawngtp** · 12-21-2010

THIS^^

**matt5112** · 12-21-2010

Look at those AL plugs again...

then look at the E3's...

and just try and tell me the AL's are cheap and the E3's are not.

**blueguy** · 12-22-2010

E3's aren't cheap. I meant cheap quality.

**Mike8410** · 12-24-2010

sorry guys to each their own, but I won't put autolites in my car. it ran like **** with them in it. I know what the issue is after digging more into it. the mass air flow sensor is what caused the problem. I replaced it now it runs like a champ, ty for the input none the less.

**neel2008** · 12-24-2010

i highly doubt the "autolites made your car run like ****".......E3 plugs=fail, you=could stand to rear a little more (not trying to be a dick just trying to give some constructive criticism here.) /thread

**Mike8410** · 12-28-2010

Next plugs that are going in it are ACDelco Iridiums. just do not like Autolites. Hell you ask for autolites around here you getting handed a bicycle helmet and sent to the tard farm. Yes i am being a dick but thats how it goes, I refuse to use cheap crap on my car including autolites.