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maxaud
07-13-2013, 04:13 AM
So a while back my 92 Celica (3sgte) would randomly shut off after driving it long distance or if I shut it off after a little drive, it wouldn't start again until it was left sitting for a bit.

The fuel pump relay also seemed like it would get considerably hot, maybe that's normal?
(I've tried a different relay as well.)

I took it to a shop and they said it was the fuel pump so I ordered a walbro and had that put it.

It's been working fine for a while now and probably have put on a few hundred kilometers but now it's doing the same thing.
sometimes the car will also take a few rotations of the engine to start where it will normally start right up.

I'm curious if anyone has had a similar issue and what it ended up being, or if anyone knows what may be causing this.

I would hate to have another fuel pump put in as I feel like that's not the solution. Maybe there's something inline that is causing the pump to overheat? I can still hear the pump turn on when turning the key (not everytime).

Thoughts?

Thanks, as always, guys.

Facime
07-13-2013, 10:02 PM
I would definately suspect an obstruction in either the feed line or the return causing a pump overheat situation. Walbro's are notorious for not liking getting hot and start to whine pretty loudly if they are stressed. You might also want to check the pressure regulator and the vac line running to it.

Diagnostically i would hook up a fuel pressure gauge to it and start monitoring it under various conditions.

maxaud
07-13-2013, 10:54 PM
Thanks for the suggestions.

The original pump was working when I removed it (stock Toyota one) for this very reason. I'm guessing it was misdiagnosed.

Where is the pressure regulator?

Thank you!

Facime
07-13-2013, 11:52 PM
stock 3SGTE? Its on the end of the fuel rail. There is a vac line to it and a larger hose that is the fuel return back to the tank. You can pull the return line off the regulator and blow air back to the tank and see if that flows smoothly.

Also, not stated but seems pretty obvious change your fuel filter if you havent already.



Fuel pumps really have two issues to be aware of. They have to push enough volume and they also have to build enough pressure. Often, a previously stressed pump will flow fine but not generate enough pressure. Flow can easily be tested with a catch can and a stop watch, but pressure requires a gauge to test it. If Im not mistaken the 2nd gen 3SGTE doesnt have a shrader valve on the rail but you can fabricate a connection from the cold start injector line.

maxaud
07-14-2013, 12:18 AM
It's a relatively stock 3SGTE (WTA Intercooler). I've only added a downpipe and MR2 bypass valve.

Where is the fuel filter? I assumed it was in the tank..

Thanks again.

Facime
07-14-2013, 04:11 AM
not sure its in the same place on the alltrac as on the GT, but on my 92 its under the hood directly below the brake booster, bolted to the frame.

maxaud
07-14-2013, 05:07 PM
Ok, thank you. I'll follow the line off the fuel rail, that most likely would lead to it.

alltracman78
07-15-2013, 12:04 PM
Did that fix it?

It sounds like the coil is going to me. You don't see many Toyota fuel pumps going bad.....

alltracman78
07-15-2013, 12:09 PM
And when it won't start, are you checking for spark and fuel?
If it has spark it's obviously not the coil.

If the pump and FP relay are fine, it may also be the COR [also controls the fuel pump].
You can actually bypass the FP relay with a jumper, to make sure that's not the problem.
The 5SFE powered Celicas have a factory jumper instead of a relay [in the same location], works better than jamming spade connectors in there.

maxaud
07-15-2013, 07:17 PM
Haven't had a chance to try anything yet. Next time it has the problem I was going to try the fuel pump relay mod.
I have yet to check the fuel filter although I'm sure it could use replaced.

Facime
07-15-2013, 08:35 PM
Diagnostically speaking, a troublesome fuel pump or a system with obstructions will manifest in poor running above idle or under load that slowly gets worse until the engine dies. Usually with just a minute or two of waiting it will restart, but often times will only idle.

Alternatively, if the system just seems to shut off randomly, acting more like you turned the key off suddenly, and wont refire after a minute or two and requires a full cool down to get it to run again, that is certainly more indicative of an electrical problem and a coil would be a definate suspect. Resistance in a wire can also cause a relay to pop on and off (relays can often be switch around to rule out the realy itself).

hope that helps, let us know what you find.

maxaud
07-15-2013, 09:47 PM
I'm assuming it's related to the relay as it gets VERY hot when I encounter this issue. Also, I've looked at the wires to the relay and the blue/orange wire is a bit glazed as if it's gotten hot too.

Facime
07-15-2013, 11:48 PM
corrosion in the connections at the relay is a possible cause, also a bad ground in the pump power circuit (not sure where that sustem grounds, but its probably not far from the actual pump which is in the tank) could cause that.

90GTS
08-06-2013, 01:13 AM
My car got the same symptoms when the coil was going bad. I also thought it was the fuel pump so I replaced it. It ran but then there are times it hard to start and at times it won't start but it cranks. Then after awhile to a day it will start again then finally it won't anymore. I found out it was the coil. Check coil resistance.

maxaud
08-06-2013, 07:59 PM
Thanks, I'll probably just replace the coil for good measure.