No Fuel Pressure! - Toyota Nation Forum : Toyota Car and Truck Forums

Leviathan66610 · 04-14-2009, 04:36 PM

I have a 92 5sfe camry automatic. I've almost never had any problems with it ever, but recently I backed out of my driveway, got it down the road, and suddenly it just stopped. After checking this and that, I realized it was a fuel issue and not spark. I've managed to narrow down the issue and it has to be some kind of electrical problem. I removed the fuel filter, and turned the ignition on and there is absolutely no fuel coming through the line at all. So naturally I replaced the fuel pump. Still no start, but here's the thing: When turning ignition on I cannot hear the fuel pump make any noise. I checked all fuses and I even replaced the efi main relay. The chilton manual says to also check the circuit opening relay, but I have no idea where that is. From what I understand it is supposed to be some kinda switch that shuts fuel off in the event of an accident, but I've no idea how it coulda shut itself off! Any ideas or suggestions would be greatly appreciated.

hill8570 · 04-14-2009, 05:27 PM

I'd start troubleshooting using the instructions at http://www.camrystuff.com/manuals/Gen3/eg1.pdf starting at page 177 . Use an unbent paperclip instead of the SST they refer to to bridge the connections on the Data Link Connector (DLC). DLC1 is inside the engine bay, passenger side corner near the firewall. Just flip the cover open -- the position of the terminals are clearly labelled on the underside of the cover.

Oh, and the position of the circuit opening relay is shown in the same manual on page 169, but bridging using this jumper bypasses that relay.

Leviathan66610 · 05-09-2009, 11:28 PM

After performing extensive research, I have still not managed to get this car started! I have checked all fuses, all relays. For the heck of it I replaced the EFI Relay, the Circuit Opening Relay, And even the ECM. I used a paperclip to bypass fp and b+ on the dlc and fuel immediately started squirting out. I understand doing this bypasses the relays so I know the wiring to the fuel pump should be good but it might be bad around where the relays are maybe? Since my car uses a MAP sensor instead of a MAF, could it be the MAP? Any suggestions, any thoughts, PLEASE I'M ABOUT TO PULL MY HAIR OUT!!!

hill8570 · 05-10-2009, 11:06 PM

Quote:

Originally Posted by Leviathan66610

After performing extensive research, I have still not managed to get this car started! I have checked all fuses, all relays. For the heck of it I replaced the EFI Relay, the Circuit Opening Relay, And even the ECM. I used a paperclip to bypass fp and b+ on the dlc and fuel immediately started squirting out. I understand doing this bypasses the relays so I know the wiring to the fuel pump should be good but it might be bad around where the relays are maybe? Since my car uses a MAP sensor instead of a MAF, could it be the MAP? Any suggestions, any thoughts, PLEASE I'M ABOUT TO PULL MY HAIR OUT!!!

Duff MAP sensor won't cause this problem. Jumpering FP and B+ bypasses all but the main EFI relay (i.e., the A/T Park/Neutral Switch, the Circuit Opening Relay, and the Starter Relay). Quite possible there's a wiring problem, but there are also a couple of fuses that could be giving you problems. Does the engine turn over when you try to start it? If so, I think that rules out fuses.

hill8570 · 05-11-2009, 02:56 PM

Me again. Take a look at the wiring diagram at http://www.camrystuff.com/manuals/Ge...ry94wiring.pdf , starting at page 93. Don't run away screaming -- this diagram isn't too bad once you get the hang of it, and it's the only way to go if you're trying to troubleshoot wiring issues.

On the bottom-right side of page 93 you can see the fuel pump, and the light-blue-with-black-stripe wiring running back from it to the circuit opening relay. That part you've shown to be correct when you jumpered B+ and FP together at DLC1 (upper right corner of page 93). And that's pretty much the only part that you've proven correct.

I'd probably start troubleshooting by pulling the circuit opening relay and checking that the basics look good (terminal 2 -- powered from main EFI relay -- has +12V when trying to start; terminal 3 -- powered from the starter relay -- has +12V when trying to start; terminal 6 is a good low-resistance connection to ground; terminal 1 is +12V when trying to start). IIRC, terminal 4 (FC "Fuel Cut") only gets involved once the engine is running.

Hopefully, probing around on the terminals of the circuit opening relay will show some wierdnesses, and we can back-trace from there.