04 GP GT2 need help w/ few quirks (and tune up info)

[Project84]

First and foremost, hello and thank you for taking interest in helping me out!

Working on my girlfriend's '04 Grand Prix GT2 periodically and I've noticed one problem in particular that is driving me nuts... the intermittent stall at start up.

I did a forum search and I came up with about 15 different scenario's but nothing was really concrete.

The car intermittently starts up and has very rough idle for 2 or 3 seconds then dies. Most times if you restart the car it's fine, sometimes it'll stall a second time, then you must give it some pedal to keep it running on the 3rd attempt. As soon as it finds a steady idle it's fine.

From reading on here it seems like the general culprits are the MAF, fuel pump, or fuel filter. The car has 100k miles on it and it's time for a tune up... fuel filter will be on the shopping list along with plugs and wires.

Next question:
During this tune up, what are the usual aftermarket plugs/wires suggested for a daily driven (no mods, no interest) '04? I typically use NAPA silicone wires and NGK plugs in all my cars but this isn't my car and I want to make sure whatever I put on there will be a quality part that is widely used.

Final question:
Since the car has just rolled 100k miles, I assume it's recommended to have the tranny flushed. Is this correct? Are there spin-on filters and a trans dain hole, or should I take this car to a shop?

Thank you!

[Vegas~Blown]

The car intermittently starts up and has very rough idle for 2 or 3 seconds then dies.

I'd say a gummed up throttle body / idle air valve. pretty easy to do and at 100K it probably needs it.

I typically use NAPA silicone wires

I use napa wires with no problem -- others say stock. either way.

Final question:
Since the car has just rolled 100k miles, I assume it's recommended to have the tranny flushed.

no, probably just drop the pan and do the filter would be fine.

Are there spin-on filters and a trans dain hole, or should I take this car to a shop?

no spin ons, and no drain on the pan... but you shouldn't take it to a shop either. get yourself a good filter and some Dex6 and you're good to go. I'd do it myself just to make sure the fluid is right.

good luck.

[Project84]

Thanks, will do!

[cerick08GP]

First and foremost, hello and thank you for taking interest in helping me out!

Working on my girlfriend's '04 Grand Prix GT2 periodically and I've noticed one problem in particular that is driving me nuts... the intermittent stall at start up.

I did a forum search and I came up with about 15 different scenario's but nothing was really concrete.

The car intermittently starts up and has very rough idle for 2 or 3 seconds then dies. Most times if you restart the car it's fine, sometimes it'll stall a second time, then you must give it some pedal to keep it running on the 3rd attempt. As soon as it finds a steady idle it's fine.

From reading on here it seems like the general culprits are the MAF, fuel pump, or fuel filter. The car has 100k miles on it and it's time for a tune up... fuel filter will be on the shopping list along with plugs and wires.

Next question:
During this tune up, what are the usual aftermarket plugs/wires suggested for a daily driven (no mods, no interest) '04? I typically use NAPA silicone wires and NGK plugs in all my cars but this isn't my car and I want to make sure whatever I put on there will be a quality part that is widely used.

Final question:
Since the car has just rolled 100k miles, I assume it's recommended to have the tranny flushed. Is this correct? Are there spin-on filters and a trans dain hole, or should I take this car to a shop?

Thank you!

You have a pretty good line on you stalling problem already. Just as you have researched your problem could be in a few areas. IMHO I wouldn’t focus on the fuel pump or fuel filter, I say that because the 04+ GPs have a much different system than the 97-03 GPs. I would start with checking for vacuum leaks and the MAF. And who knows changing the plugs might fix it. To answer your question, NGK plugs are excellent. And plugs wires are pretty much the same; I will caution you from using a “universal” set. Get a set cut for the GP.

On the tranny fluid, a pan drop is easy but messy. Get yourself a big catch pan. Also, when you put the new filter in make sure it is fully seated. And make sure you use Dexron 6 fluid.

Good luck.

[dirtmaster88]

I had the exact same problem in regards to starting the car up. I took off my throttle body and almost threw up from how much carbon was built up. I was literally able to grab chunks out just using my fingers. A can of throttle body cleaner and elbow grease solved the problem. Be careful not to spray any of the cleaner directly into the throttle body if you have a blower, it will damage the coating on the rotors. It's pretty simple on an 04. Here's an excellent writeup: Grand Prixs Of North America • View topic - clean your MAF & Throttle Body

[Project84]

The car is N/A.

Well, crap.

I just read that the OEM plugs are iridium? Is this correct? Gap at .060? I had priced out regular NGK's. She's not gonna be happy about that!

Thanks for all the leads, guys.

It's looking like:

Air filter
Fuel Filter
Trans Filter
Plugs
Wires
Clean TB

I'm doing these same things on my '01 SL1 I just bought w/ 99k. Lots of work ahead of me.

[cerick08GP]

The car is N/A.

Well, crap.

I just read that the OEM plugs are iridium? Is this correct? Gap at .060? I had priced out regular NGK's. She's not gonna be happy about that!

Thanks for all the leads, guys.

It's looking like:

Air filter
Fuel Filter
Trans Filter
Plugs
Wires
Clean TB

I'm doing these same things on my '01 SL1 I just bought w/ 99k. Lots of work ahead of me.

Well, I have some good news and bad news.

The good news is you don’t “need” the $10 iridium plugs, in fact some ppl swear by the $1.50 Autolite 606s. For stock GT, you can use any plug you want the only difference is longevity. Check that they are set to .060" for anything you put in.

Also, if you figure out a way to change your fuel filter let us know. We’ll talk you into taking some pics and doing a write up on it. Like I mentioned before, I wouldn’t worry about the fuel pump or filter atm.

Missing from your list is a gallon of Dexron 6.

[Project84]

Alright, what's up with the fuel filter?

NAPA # FIL3946 shows it. Doesn't look like an in-tank style... what gives?

Is it located somewhere that'll make it a PITA?

Autolite 606's.... check. Or are regular NGK's okay? I prefer brand loyalty.

Make that 2 gallons ATF, I'll be needing some for my Saturn as well.

[Poil336]

i have autolite 606's right now, they'll be fine. my car will sit for a week at a time in less-than-stellar weather and start right up, no missing or anything, same performance

as far as everything else, i'm not exactly an expert on it haha. wish i could help more

[Project84]

oops...

[Project84]

Well, things got backburnered for a while and now I'm ready to get back on top of this.

I'm looking at 4 different Autolite 606 spark plugs...

They have:

XP606 Iridium $6.49ea
ASP606 Copper $1.69 (are you guys suggesting these are fine?)
AP606 Platinum $2.79
APP606 Double Platinum $3.99

Thanks guys