85 died and wont start (fuel problem)
Thread Starter
Cruising
Joined: Jan 2009
Posts: 14
Likes: 0
From: Tucson AZ
85 died and wont start (fuel problem)
Leaving my apartment, my car ran until I got to the stop sign and then it suddenly died. No sputtering or hesitation, just died like I turned off the key. I tried restarting and it cranks like it should but never fires.
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Forgot to mention I replaced the fuel filter about 9 months ago.
Thanks in advance
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Forgot to mention I replaced the fuel filter about 9 months ago.
Thanks in advance
Last edited by dallas3246; Mar 6, 2010 at 04:14 AM.
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
Leaving my apartment, my car ran until I got to the stop sign and then it suddenly died. No sputtering or hesitation, just died like I turned off the key. I tried restarting and it cranks like it should but never fires.
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Thanks in advance
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Thanks in advance
Safety Car
Joined: Oct 2004
Posts: 3,830
Likes: 3
From: Granada Hills CA
Leaving my apartment, my car ran until I got to the stop sign and then it suddenly died. No sputtering or hesitation, just died like I turned off the key. I tried restarting and it cranks like it should but never fires.
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Forgot to mention I replaced the fuel filter about 9 months ago.
Thanks in advance
So I checked the codes and only got 12. I then checked the fuel pump fuse and it is good. I also tested fuel pressure at the schrader valve and it is 0 psi. I tried to turn on the fuel pump by connecting 12V to terminal G of the diagnostic port and I could not hear the fuel pump turn on. I also just added gas so that isnt the problem. Is there any more diagnosing I can do before I replace the fuel pump?
Forgot to mention I replaced the fuel filter about 9 months ago.
Thanks in advance
I speak from experience. My FP seemed to work as well which led to a host of parts being replaced based on guesses prompted by well meaning posters. TPS, FP pressure regulator, ignition module, checking relays, replacing sensors. When all was said and done it turned out to be the FP was bad and MAF that needed replacing. Not that having the new parts on is bad, maybe just not necessary.
Good luck.
Team Owner
Joined: Jan 2003
Posts: 20,333
Likes: 262
From: Summerland B.C. Canada
You say you checked the pump fuse, visually, or did you test it with a meter ?
Put the 12v back on "G" and see if 12v is making it to the pump fuse.
If it is, check for 12v at tank. If it is still there, buy a new pump.
Put the 12v back on "G" and see if 12v is making it to the pump fuse.
If it is, check for 12v at tank. If it is still there, buy a new pump.
Team Owner
Joined: Jan 2009
Posts: 73,568
Likes: 33
From: Somewhere in Mo
St. Jude Donor '09-'10, '14
Before you start replacing parts randomly based on guesses get her to someone who can diagnose the problem accurately.
I speak from experience. My FP seemed to work as well which led to a host of parts being replaced based on guesses prompted by well meaning posters. TPS, FP pressure regulator, ignition module, checking relays, replacing sensors. When all was said and done it turned out to be the FP was bad and MAF that needed replacing. Not that having the new parts on is bad, maybe just not necessary.
Good luck.
I speak from experience. My FP seemed to work as well which led to a host of parts being replaced based on guesses prompted by well meaning posters. TPS, FP pressure regulator, ignition module, checking relays, replacing sensors. When all was said and done it turned out to be the FP was bad and MAF that needed replacing. Not that having the new parts on is bad, maybe just not necessary.
Good luck.
As far as the issue at hand it appears the pump is either bad or it is not getting the correct current or the relay is bad.
If the pump is original I would replace it anyway. If it isn't the cause it will be sooner than later.
The fact is you know you have a fuel issue and most likely the pump or the feed to the pump. Make sure you are getting the correct amount of volts as Agent86 stated.
Last edited by RetiredSFC 97; Mar 6, 2010 at 07:49 PM.
Advanced
Joined: Dec 2007
Posts: 52
Likes: 0
From: Waynesville Ohio
Check for 12V and good ground at the pump. There is plug near the filler neck where you can check, three wire, one is ground, one is 12V for the pump and the other is the fuel level sensor. You could also apply 12V and gound directly to the pump at this plug on the pump side to see that the pump works.
Thread Starter
Cruising
Joined: Jan 2009
Posts: 14
Likes: 0
From: Tucson AZ
Thanks for all the help. Turns out it is the fuel pump. I put 12 V across it and nothing happens. Unfortunately I have a new problem now. As I was pulling the fuel sending unit I snapped off one of the bolt heads and there were already 2 that are broken. And of course all 3 are right next to each other. Any suggestions as to how to proceed. I really don't want to have to drain the gas tank...
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
First, soak the bolts in rust dissolving chemical for 24 hours.
THEN
you can drill the bolts and use an easy out to remove them. start with 1/8" drill for a pilot hole, and then go to the drill size for the easy out. Be sure to drill slow, and be careful if you smell gas fumes, you could blow yourself up.
Replace all the other ones as well, and use some sort of copper based seal, non hardening pipe dope, like permatex non hardening formula. The gas is cleaning up the bolts, and the steel to steel is rusting the bolts in place.
be sure to proceed slow, or you will certainly have to take the tank out.
THEN
you can drill the bolts and use an easy out to remove them. start with 1/8" drill for a pilot hole, and then go to the drill size for the easy out. Be sure to drill slow, and be careful if you smell gas fumes, you could blow yourself up.
Replace all the other ones as well, and use some sort of copper based seal, non hardening pipe dope, like permatex non hardening formula. The gas is cleaning up the bolts, and the steel to steel is rusting the bolts in place.
be sure to proceed slow, or you will certainly have to take the tank out.
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