05 grand prix base

**kmk2005** · 07-09-2011

ok so this is what it does, it hesitates sometimes. it don't do it all the time and when it is doing it, i can stop, shut it off and restart it and then it's ok again. it's mostly when i'm accelerating it notice its like gutless and kinda shifts hard. My boyfriend thought catalyic converter so we just replaced that and it still does it. we also replaced the plugs and wires and that didnt help. My engine light is on.. and the only code the computer brought up was that there's a small evap leak or the gas cap isn't tight or something..which it is. i'm getting really frustrated with this. lol plez help any ideas?

**kmk2005** · 07-09-2011

ooh and it idols just fine. It's mainly when i'm taking off and i have noticed it when i am up to speed once in a while..

**rynoman03** · 07-09-2011

Post the trouble code.

Like P0xxx.

My wifes g6 does this when it's hot and the dealer can't figure it out either.

Whens the last time you changed the fuel filter ? (Simple fix.)

Run a can of seafoam through the gas tank to clean the injectors.

YouTube - ‪Seafoam Motor Treatment and Introducing NEW Seafoam Spray‬&rlm;

**kmk2005** · 07-09-2011

I'm not sure what the trouble code is? I mean i don't know it offhand anyways? I just bought this car about 4 months ago and so i've never replaced the fuel filter anyways.. I'm pretty sure the last owners didn't keep real good care of it so hard telling when they had it changed?

**kmk2005** · 07-09-2011

is seafoam like fuel cleaner? cuz i know my bf ran some kinda clean through my gas tank..

**rynoman03** · 07-09-2011

Ya fuel and engine cleaner. It's the best on the market in alot of peoples opinions. Do it through the vacuum line like that video shows.

We just need to the Engine Light code that comes up to help diagnose. Take it to autozone or someplace and have a scanner hooked up to it. Then report back with the "P" code.

**kmk2005** · 07-09-2011

ok will do. thanx for the help

**rynoman03** · 07-09-2011

NP

**joshv** · 07-09-2011

my o4 gp has the same thing, and iv replaced the gas cap and its allways on, its just a stupid code problem it used to bother me but now i dont care lol

**kmk2005** · 07-10-2011

you engine light is on? or your gas cap light? lol thats if there is even a gas cap light? cuz i only have the engine light on. The previous owners lost the manual so i don't have a handly manual to look things up quickly

Your car does the hesitation stuff though?

**TDgrand** · 08-13-2011

Originally Posted by kmk2005

ok so this is what it does, it hesitates sometimes. it don't do it all the time and when it is doing it, i can stop, shut it off and restart it and then it's ok again. it's mostly when i'm accelerating it notice its like gutless and kinda shifts hard. My boyfriend thought catalyic converter so we just replaced that and it still does it. we also replaced the plugs and wires and that didnt help. My engine light is on.. and the only code the computer brought up was that there's a small evap leak or the gas cap isn't tight or something..which it is. i'm getting really frustrated with this. lol plez help any ideas?

My 2005 3.8 N/A base has the same symptoms. The car hesitates only once in a while and I can shut it off, then start and it will go away. The acceleration is exactly as yours, sluggish and jerky. My engine light is on with a p0455 code (leak evap system). The dash information says check gas cap. The cap is on and have purchased new ones.

Have you found a solution?

If anyone knows the solution or how to approach this situation let me know.

**kmk2005** · 08-14-2011

Ugh ya I have not found a solution yet unfortunatly. I know replacing the spark plugs and wires, and replacing the catalyic converter didn't help. It still does it. If you happen to find a solution before me you should let me know

**GTPSHAWTY** · 08-14-2011

i changed my whole evap canister.. and lines.. on my 97 it turned da ces light off.. different year.. same light..

**kmk2005** · 08-14-2011

Did your car do the hesitating and feel boggy though? and did it help when you replaced that?

**blueguy** · 08-16-2011

With the newer GM cars...I've found the new style EVAP canisters to fail quickly...they are pretty cheap...like 20 or 30 bones. My Cobalt I had chucked 2 EVAP canisters during the couple years I owned it. Also...'04+ cars suffer from gunked up throttle body issues...which can cause hard starting or stumbling...remove the intake tubing...unbolt the 4, 10mm bolts that hold the TB on...unplug it...yank it off and clean it with brake clean and a towel you don't care about...and toss it back on.

**TDgrand** · 08-17-2011

Originally Posted by bluegtp91

With the newer GM cars...I've found the new style EVAP canisters to fail quickly...they are pretty cheap...like 20 or 30 bones. My Cobalt I had chucked 2 EVAP canisters during the couple years I owned it. Also...'04+ cars suffer from gunked up throttle body issues...which can cause hard starting or stumbling...remove the intake tubing...unbolt the 4, 10mm bolts that hold the TB on...unplug it...yank it off and clean it with brake clean and a towel you don't care about...and toss it back on.

Thanks for the info.

Is the canister located about the drivers side wheel well?

**blueguy** · 08-18-2011

It should actually be in front of the intake manifold on the middle/left hand side.

If its in the same place as my '98.

**sk8rh84** · 08-23-2011

For your car (04+), yes. Rear drivers wheel well. If I recall, one bolt to remove the canister and bracket holdin it on. It is slightly behind the wheel well almOst on top of the muffler (if you have a muffler on the drivers side). Easy and cheap fix for a pain in the ass problem.

Exactly the same symptoms as you. Gas cap warning on the DIC and occasionally a CEL that would go away the next day. Bought the gas cap ... Waste of $40 from the dealer. Went in and asked. They told me right away what to replace. They said that they stock a few because they apparently go out all the time. Haven't had an issue since I replaced in January (fingers crossed)

**TDgrand** · 09-14-2011

So for an update, I replaced the evap canister about 3 weeks ago and the check engine light and DCI have been clear, no issues. The canister on my 05 is located right by the fuel filler neck, behind the rear drivers side wheel.

Took about all of 15 min, 1 bolt to remove.

Part: ACDelco 214-2147 OE Service Vapor Canister Purge Valve

Thanks for the help! Up next cleaning the throttle body.