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Won't start! Please help!

fpgt17

fpgt17

New member
Okay first of all i am new to this forum so please take it easy on me if i do something wrong!

I have a 99 Grand Prix 3.8l and i went to start it a few days ago. It was cold out (dont know if it matters) and it started fine and ran for about 1-2 minutes and then it started shakeing as if my motor mounts went out. (motor rocking hard back and forth) I quickly shut the car down becasue i thought maybe i lost a coil and was only running on four cylinders. When i tryed to start it back up it would turn over just fine but not start. Felt like it wasnt getting fuel or gas. I left for the weekend and when i got back today i tore into her. I started with the coils and had them tested... they thought one "might" be bad so i threw a new one in. Then i had the ignition control modular tested. they ran it multiple times and it was fine. I dont have and check engine codes on, it has gas (i pulled off the fuel lines on the rail and turned the key on and it pumped out). The fuel pump is turning on and bringing fuel up....haven't had any other problems or concerns leading into this.. ANY IDEAS???? It is way to cold for me to keep working on it outside my college with hardly any tools up here (all at home). Please help if you have any ideas or have ad this problem.
Thanks!
 


well when i removed the fuel line on the fuel rail the fuel shot out... wouldn't that mean i have pressure?
 
you might have pressure, but it doesnt mean you have enough. The regulator could be shot. Your car wont start with under 32Psi rail pressure
 
Could be a weak fuel pump thats for sure, like 01gpgt01 said, without correct pressure, the car wont run right. My car did the same thing and i replaced my pump and no problems since.
 
well that doesn't sound too off the wall... My fuel gauge doesn't work and i have heard it is a cause of the sending unit on the fuel pump... (common Problem) To test it should i just unhook off the fuel rail and hook the tester on there? Then see what i am reading.... It sucks up here with limited tools right now....
 


Alright sweet! i will try that... Kinda hope its it... already spending too much money. If it was then it would fix my fuel gauge problem too.... can't be mad at two birds with one stone. If i can get to it tomorrow i will... ill let you guys know! Thanks a TON!
 
Well i tested the fuel pressure today at the rail.... I was onlu getting 10 PSI at key on acc! But my pump still sounds strong... So i then tryed to turn it over and watch to see if the pressure was any different. When i turned it over it then backfired and smoke came out from the back and front of the motor... Seems as if its off time and the exhaust valve was open instead of the intake. Even tho i didnt have much pressure at the fuel rail i feel like its the CPS... What do you guys think? Its getting too cold and i am limited on tools so this has gotta get figured out fast lol
 
im thinkin ur fuel pump is shot.. pump noise doesnt always mean its running strong. whens the last time u changed fuel filter.
 


Ya i think like 34 Psi is what is supposed to be there.... Fuel filter is maybe 4-6 months old. It keeps sounding like its my fuel pump. My gauge doesnt work which is a problem with the sending unit but idk, maybe the pump is goin out. Any way to test it without dropping the tank? If not whats the easiest way? But that doesn't really explain the backfire from the motor/ the smoke that came out of it. Fuel pump makes sense untill i think about the backfire when its turned over.
 
40-42 psi With the vac line attached. is normal, 48-53ish I think is what is normal with the vac line pinched Your car will not start with under 32psi (with the vac line attached). Atleast mine wouldnt. If you hear the pump priming Id venture to say its the Fuel pressure regulator. Pull the vac line off of it and see if theres gas in the line, or if it smells of gas. That would indicate a leaking Diaphram
 
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you dont need to drop the fuel tank to change the pump.

remove the lower half of the rear seat and pull up the insualtion.

there should be a panel for fuel pump access.

Only very early 97 models didn't have that.
 
SWEEET! I will test the reg. this weekend and then if its good i will go for the pump. Glad it has an access door!!!!
 


OKay.... well the regulator is good and i have 50 psi at the rail now. (must of been a bad test before)
I pulled out my spark plugs and they were shot... so i put new ones in. They were covered in gas and had all kinds of build up on them. My MAF sensor was bad so i think it was putting too much gas in. SO before i put in my new spark plugs i did a compression test.... i have 150 across the board except the front middle cylinder which is giving me 0!!!!!!!!! :( I dont like it... But if it was a head gasket wouldnt i get lower compression on more than one? the other five are fine!.... maybe its all gummed up and clogged from the gas/carbon built up. When i did the pressure test it was sucking up all kinds of build up. So what do you guys think? hopefully not a head gasket..... :( i don't have the money to fix that.
 
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