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EJ22 swap starts & runs for 20 sec, then dies.


robcor2
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Got everything installed, and powered, ('92 EJ22 in an 85 GL-10) the engine will start and run for about 15 - 20 seconds and then dies. Throttle causes it to die quicker. I have the fuel pump relay powered directly off the ignition switch so the pump comes on and stays on in crank and run. I have checked all vacuum connections. Swapped out known good MAF, TPS, IAC, crank position sensor, tried 2 different ECU's and made sure that the ECU gets a start signal from the ign. switch, checked all grounds, and added some redundant grounds to be sure. I was able to keep it running for longer by spraying starting fluid into the air intake tube, but nothing else seems to be presenting itself as a problem. Any help would be greatly appreciated.

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If it was the ECU pulse, wouldn't it cut out immediately instead of sputtering out like it is doing?

 

It was running before the swap, except for major headgasket issue.

 

Gonna rent a QUALITY fuel gauge and test the pressure....it seems to possibly be a fuel pump issue.

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ECU codes? :rolleyes:

 

Most likely not a fuel supply issue unless the pump is losing power somehow..... which is possible I suppose given how you claim it's wired. Why is the ECU not controlling the fuel pump relay? Perhaps the ECU is shutting off the injector pulse because it doesn't see a relay coil for the fuel pump - potentially a safety hazard in an accident if the fuel pump should continue to run thus the ECU's software shuts it down..... you haven't got it wired correctly so it could be anything! Get the wireing proper and find out if the ECU has any complaints - it's a self-diagnostic system.

 

GD

Edited by GeneralDisorder
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my supra had a the same thing happening a while back.. would run for up to 20 seconds then die.

 

it took a fuel pressure tester to show me the problem. the pump would build pressure when starting but would drop immediately after engine was running.

 

my issue ended up being a leak, but in my search for a solution i checked the fuel pressure regulator, fuel rail damper, filter, and pump.

 

it may be related to the pump not being triggered by the ecu, but how would the ecu know? can it sense electrical load? or perhaps its part of an electrical loop?

 

would make sense in the above mentioned accident scenario when you would want that to shut down immediately with the engine.

 

so yeah, check the fuel pressure, as i recall it should be between 40-45psi, someone correct me if im off

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Yes the ECU can sense the load on a driver circuit - that is how it determines when solenoids fail, etc. Thus it can sense the load of a relay driver coil just as it senses a solenoid driver coil. Who knows what the ECU's programming would do without a fuel pump relay present...... Maybe nothing at all but i can tell you that few of us would know because we don't wire them like that!

 

GD

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I have also had this happen when I forgot to hook the 1" rubber hose onto the Idle Air Control (IAC) so it was pulling unmetered air in.

 

So check you have no leaks between the MAF and the throttle body and IAC. No unhooked PCV hoses, no untightened clamps, ect.

 

It will start because of the cold start enrichment, but as soon as the ECU sees the rpms come up, it stops that, the MAF indicates no air getting sucked into the engine, so it puts no fuel in and the engine dies. A failed MAF can also cause this.

 

Failing that, go after the fuel pump. Also make sure the hose leading from it to the tank isn't kinked.

 

Don't spray ether into an engine, it's bad stuff and can easily lead to cracked pistons. It's for direct injection diesel engines only. With IDI diesel engines it can knock the prechambers out of the heads and destroy the engine. Gas engines aren't strong enough to take the detonation of ether at all. I trashed a nice old chrysler 6 using ether to get it rolling when I was younger and dumber.

Edited by WoodsWagon
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WooHoo:banana::banana::banana::banana:

 

Thanks GD for the advice. Rewired through the ECM....in the process found a broken wire and fixed it. Don't know which helped, but.......IT"S RUNNING!!!!!

 

In fact laid down rubber in 2nd gear. DANG!

 

Still have a bunch of stuff to clean up. The exhaust has a rattle that I need to correct. The suspension is toast and needs a sport suspension anyway. The brakes are a little squishy, but I have pads ready to go. But.....I think she is good to go! Thanks for the help everyone. I am sure I will have more questions, but for now I am reveling!...and revving!

 

Next up. Suspension and getting the 14" pugs powder coated and put on....and getting all the tools out of it.lol

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  • 4 months later...

I know it is an old thread, but I want to thank everyone who helped me get stuff done on this thread and a few others. The project has gone as far as it can go.....used it for a back-up driver this summer and it is running okay...it needs someone else to take it to the next level though. I have posted it on the Subarus for sale portion of this site. Please take a look if anyone is interested in a car mostly done.

 

Robert

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