Thread: GP Wants To Stall

I guess I am going to start from the begining. Hope this isn't going to be too long for evryone. Just want to give ya'll the scoop of what I've been through and done.
Here it goes, In 2005, while deployed overseas, my transmission went out on my wife. So the car set for about 2 years. Got that fixed and have been driving her for almost a year when it hits. I was going to work one morning and went to give her some go pedal and she starts hesitating. Took it by Auto Zone for the free scan. They gave me the list of possibilities. It said that I had multiple random misfires(P0300), IAT(INTAKE AIR TEMP) circuit(P0113), and fuel trim bank one condition. Luckily I also have a GT of the same year, so I could swap parts until I found the one that worked. Unfortunatly nothing did. I also changed plugs and wires. I Put MSD 8.5mm wires and NGK TR55IX plugs. So I sucked it up and took it to the dealer for a scan. That's when I found out that I had a coil pack going bad(the 3 & 6) and my EGR valve was bad. Got home, stole a coil pack from the wifes GT, and bam, problem fixed. Put hers back on and ordered me a set of the MSD Blaster coil packs. Installed them, made a few minor adjustments and I'm back in business. SO I THOUGHT!!! Heading to work on morning, went to pull off base, and she dies. Threw it in neutral, and she fired right back up. Explain more on that in a few. Not fun when your car dies and there's traffic coming at you! Thought it may have been from the car sitting for about a month while I tried to debug her. That happened last Friday(April 11). The today(April 16) same thing. Went to pull out and dies. Fired up, went a few seconds and died again. Fired right up, and went on my way. Got home, scaned the PCM, got smart and bought my own scanner, and got two codes: P0300-Random/multiple cylinder misfire detected and aP0171: System too lean(bank 1).
Now to describe what it's like when it happens. I start her up in the morning, and she acts like she wants to shut off, idles rough and so on. Thought maybe it was because the screen is out of the TB. Gone when I got her. ANYBODY HAVE ONE THEY DON'T NEED? Then when I go to pull of base, I sit there for about 5 or 6 minutes waiting on traffic, she has a good idle, not trying to die or anything, and I go to pull off and silence. She goes about 10 feet and dies. No sputtering or hesitation, just dies like she lost all electrical power. Like I said before, She fires right back up. I am stumped. don't see any loose connections. Thought if it was a vacuum leak, it would do it every time I stop. And it also seems that after she warms up good, the idle gets more rough. Would my bad EGR valve be causing this. Read that it wouldn't affect the car, would only make the check engine light stay on. I'm just stumped. Tired of spending money on stuff that doesn't fix the problems. So if any one can give me some insight, I would greatly appreciate it.
Here is a list of mods done:
3.4 " SC pulley
Short ram air intake
No mufflers- loud as heck
MSD coil packs
MSD 8.5mm wires
NGK TR55IX plugs

Thanks in advance for evryones help and if anyone needs any more info, I am on here several times a day checking things out to see if I can give some advise. OH, sorry for writing a book, just want to give you all the info I can

when my ignition module went out it did something like that, a bad coil may have killed teh module (not sure swap test would confirm)

Originally Posted by stlmo_gtp

umm do you have any video clips of what a GP with no muffler's sounds like ? just curios, anyway this is what happened to me my CPS went bad then my Cam Sensor and the Fuel Pump and i had these common problems, my car still is idling rough every now and then right now, but hopefully your problems aren't the same as mine because i cost me about 800 bucks to fix it, o and why are ACdleco Fuel Pumps running at $350 a pop, and you can buy some high flow ones for around $200, i should have taking that route instead but i didn't find out until a week later that you can find high flow's cheaper the stock

most of the so called high flows don't flow any more looking at the catalog specs even the walboro doesn't have the specs any better than the stock replacement (edelbrocks pumps are all walboro also and they have specs listed in catalogs at most parts stores)

Originally Posted by stlmo_gtp

umm do you have any video clips of what a GP with no muffler's sounds like ? just curios, anyway this is what happened to me my CPS went bad then my Cam Sensor and the Fuel Pump and i had these common problems, my car still is idling rough every now and then right now, but hopefully your problems aren't the same as mine because i cost me about 800 bucks to fix it, o and why are ACdleco Fuel Pumps running at $350 a pop, and you can buy some high flow ones for around $200, i should have taking that route instead but i didn't find out until a week later that you can find high flow's cheaper the stock

No I don't have any video yet. I'll try and work on that when I get OL' Girl running right again.

Originally Posted by copterdoctor

So have you even been through a tank of gas in it? I wouldn't be suprised if the fuel was too old or had a lot of water in it.

a friend of mine has a 91 mustang GT he let sit just over the winter but on very little fuel. I don't know if it was from condensation or not.... but when he went to drive his car it kept stalling just like what your grand prix did. he put in some treatment that absorbs and evaporates water from your fuel tank. (I'm pretty sure it's available at autozone, but I can't think of what he used)

Just a cheap easy fix I wouldn't overlook.

stuff is called heet it's gas line antifreeze to most people

I've ran quite a few tanks through it. I've been driving it almost a year. It started stalling after I replaced my coil packs. The other day, I pulled the coil packs and ignition module of and cleaned the mess out of it with some contact cleaner. And ( knock on wood ) I've been driving it a week now and it hasn't stalled yet. It was doing it about every 3 days. So if there is anything else that anyone can think of that I can check as a precaution, please let me know. I will greatly appreceate it. Thanks for everyones help and any advice doesn't get blown off. I check everything. No matter howw small it may seem.