Pontiac Grand Prix Forums : Grandprix

Ive had this happen three times in the last couple of days. When I was coming to a stop light the car died. I coasted to a stop, put it in park and it started right back up like nothing ever happened. The other two times happened when I was driving. The engine just stopped. My natural reaction is to step on the gas to maintain speed and then a second later it'll come back to life. The dealership diagnosed two bad coil packs and dirty injectors. Can the coilpacks cause this?

I have never heard of coil packs causing this issue.

i had pretty much the same problem with my cavalier and it was the coil packs, HOWEVER, on my cavalier it never started right back up, always took 10-20 mins for them to cool down before i could start it again

I had 93 tempo long ago and the same thing started happening. Dealer said it was the coil, so replaced that and it worked fine.

I have heard of this happening when they go bad.



I have also heard on many occasions and on one occasion experienced where the car would not go above about 3000 rpm's.

Coil packs are in the mail. I'll let you know if that solves the problem. Thing that sucks is if I take it in for a diagnosis, chances are they wont find **** and will charge me 120

my car did that and i had autozone scan it cause the SES light eventually came on. Their crappy scanner said TPS, so I replaced that. light came on again and it still said TPS so the guy said it had to either be the EGR or the intake air valve. I am in the process of re-wiring the 3.1L EGR valve I accidentally bought to work with the 3.8L plug. The pintle was stuck open and it wouldn't unstick when I tried to clean it. When the coils on my cavalier went out it just bogged down and lost power, gas was dumping out the tailpipe cause it wasn't burning, it did still run though.

The Dealership also said that my tps and pigtail where bad. I replaced it last night but didnt get a good enough connection. It was an interesting drive to work this morning... I got the coil packs replaced yesterday and its way smoother. The car hasn't died in two days so I'm guessing it was just moisture from cleaning the engine bay the other day. Let's hope I didnt just jinx myself hehe

If it does it again I'm betting it's the Cranckshaft Position Sensor. Typical symptom is what you mentioned. Car dies for no apparent reason then restarts. As the sensor dies the slow death that it does, the car will take longer and longer to restart and will die with more frequency.

I replaced coils, wires, and PCM before I found the real problem. It's a ***** to diagnose because it doesn't throw any codes. So if she dies again get the CPS replaced no matter what they tell you...it's a common problem.

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mine does the same thing but only when i beat on it a little while it dies out and i replaced the MAF sensor and the cranks shaft sensor and it stoped for a while. but now when im beating on it it died out then starts right back up when i go to start it, and also when im just coasting or going up a hill at lower rpm the rpms bounce up and down like it wants to die out but when i give it alot more gas it drives jsut fine. could the coil packs and wires be my problem?

What do your plugs look like? Pull them out and check them. Could be that you are running lean or rich and the plugs are getting fouled/damaged. Could also be wires but usually you'll get a flashing SES light as the engine will misfire. Check your codes if indeed you have had a SES light on to see if there have been misfires. Coils or coil module could be the next culpret but it almost sounds more like a fueling issue like bad or clogged injectors. Start with the basics though and go from there.

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what should i by to help with the fuel infectors? and i jsut went and baught some wires for the car. the ses light turns on then turns off a little bit later, its weird

Try cleaning your MAF sensor, I had a stalling problem like that and after I cleaned it, it went away.

lol i was told cleaning it was a bad thing to do, plus i baught a brand new one about 7 months ago so i dont think thats the prob but thanks tho

Between the time you changed your MAF and now, have you changed or cleaned your air filter? If you have a K&N Style filter those need to be oiled. Did you oil it? If so, how much oil did you put on it? Too much oil on the air filter is a bad thing. The excess oil comes off and begins to coat your MAF sensor which causes it to misbehave. So even if you only changed the MAF 7 months ago if you cleaned your air filter a couple times between now and then and over oiled it you could now have a very dirty MAF.

You can clean the MAF but you must be very gentle with it. A cotton swab with a bit of carb cleaner on it GENTLY rubbed VERY LIGHTLY over the wire will get most of the gunk off without harming it.

As for the fuel injectors, just getting some good FUEL SYSTEM cleaner will help. Don't get just the fuel injector cleaner...you want the stuff that cleans the WHOLE system. If that doesn't work it may be time for a little seafoam treatment. Nasty process but sometimes that deep kind of cleaning will help.

I'd check plugs first though as it's free and it may tell you a lot about how your car is running. That would help further diagnose the problem.

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My 07 did that crap, bad wiring connector for the MAF and something else @ the engine bay main electrical block by the air filter.

Shift hard at all? or goofy shift almost a stutter to a shift kit shift.

yes it shifts really hard then thats it in never does it again, how did you fix your prob because this is what mine is doing

ok thanks for all of your help and iwill try these things. but what is sea foam and were can i get this stuff at? and also what is a fuel cleaner you would use?

Seafoam is basically a fuel system and top engine cleaner. All the carbon and crap that gets built up in your cylinders and on top of your pistons this stuff will burn off. You can get it at any autoparts store but do a search on how to use it with a Grand Prix. Again, this is a last resort because it sounds like your problem isn't really going to be helped by using Seafoam. Just saying that if your injectors were really bad and a regular fuel treatment didn't work that perhaps the Seafoam would.

What WhiteDevil posted sounds very logical too. Check that wiring for proper connection. As for fuel system cleaner I usually use Lucus, STP, or Gummout (sp?).

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dealership fixed mine, let me see if my service record is online.

Not online, but it all had to do with the MAF wiring connection at the fuse block underhood and another connection at the same block, I think it was fuel pressure or something, it dies when its flooding, starts right back up, shutters/jerks at shifts.

Seafoam rocks, just use your brake booster vacuum line or PCV line to suck it in by vacuum till it dies, pour the rest in your gas tank.

lets sit 15-25 minutes, put on goggles and a breathing mask, start the car.