downrange383

Looking for some help.

I just completed a re-build of my 22RE. New crank, bearings, rings, new head and compete timing set and cover. Rebuild went smooth and the engine fired right up. After setting the timing, I ran it around the neighborhood and all was good. Took a short ride of about 15 miles, stopping and checking for leaks and such, all was still good. Back it in the driveway and it started missing like one cylinder was not firing. Revved it slightly and it sputtered and quit. Now it will not fire or run.

It tries to start, but will not. Took the plenum off and checked the injectors. All are getting 12V. Only thing I cannot check or know is if the ECU is firing them. I do not have a noid light to check. If you open the TPS and shoot it with starter fluid, it will run until it burns the starter fluid. Pulled two plugs and they are dry after much cranking. Any suggestions??

black diamond

i would check to make sure u have the propper fuel pressure, fuel pump? is it efi?

downrange383

It is an EFI. The fuel pump is working and there is pressure to the fuel rail. Cold start injector is working and I'm almost certain that's where it's getting some fuel when it tried to fire.

black diamond

sounds like no fuel.. efi u need fuel pressure, 30 psi? you can get fuel at the rail but it might not be enough pressure. not sure of spec, should try to get a reading. the injecters usually are switched by ground, so u could have 12v and not firing. fuel system check.

dcg9381

I'd start by by-passing the AFM control of the fuel pump. Search for 4crawler's page on fuel pumps.. you just use a jumper.

You've got spark if you'll light starter fluid and the same signals that trigger spark also trigger the injectors.. that is, the ECU decides when to trigger them both (seperate signals).

A test light or basic voltmeter should be enough to tell you if you're triggering the injectors...

downrange383

It had plenty of pressure and ran perfect for about 17 miles. If you crack fitting at cold start injector, it has serious pressure. I have read and tried every trick in the book from just about evey post I can get my hands on with info on this topic. I am totally stumpped on this one.

SoCal4Running

I wouldnt start cutting wires up till you know the problem is with them.

Although it does sound like a fuel issue have you quadrouple checked all electrical connections, air intake plumbing clamps for tightness.

rowdy235

Double check all electrical connections. Check them again. Crank it and pull the plugs and post results. That should tell us if we are getting fuel or not.

dcg9381

Or follow the provided suggestions - by-pass the AFM pump control and figure out if the injectors are being triggered. Use a 12V light if you need to.

That truck should have minimal fuel pressure unless running/cranking. The fuel pump doesn't run unless air is flowing over the AFM.

Determine where the problem is.. Happy to provide more pointers after that.

downrange383

I tested the fuel pump using the jumper and it s working. I'm trying to find a noid light to test the firing of the injectors. Have checked, re-checked, triple and quadruple checked all electrical and vacuum connections. Checked the timing to make sure it did not jump. Timing mark on main crank pulley is at 12 o'clock and timing mark on cam gear is at 12. Rotor points to #1 wire which is right where it was when we put it back together at TDC and it ran. There is good spark on all four plugs.

dcg9381

Ok, let me know if the injectors are not firing.
It would be odd to have the injectors NOT fire and still have spark.

As you've got 12V at the injector, it sounds like your EFI relay is good.
The ECU pulses the injectors by grounding them.. They ground back to the ECU. One typical reason for failure is not connecting the ground to the lower intake manifold. Outside of that, you'll have to look at the ECU.

As you've got spark, this means the ECU is getting crank/timing signals from the dizzy and ignitor.

downrange383

OK ... Very electrically inclined, so lets talk this ground. The ground to the harness is bolted to one of the six intake plenum bolts between the upper and lower plnum. The boly passes through the upper plenum with the ground behind it against the upper plenum, and into the lower plenul. This would essentially ground the upper and lower and would also ground it with the block via the intake studs and bolts. Is there somewhere else this grouns is supposed to be connected?

dcg9381

As long as the harness has a good ground to the battery and the harness ground to the plenum (either location) is OK, you should be in good shape.
To test it, you can ohm out between the plenum ground and the battery. It should be a very very low reading.

If you can confirm with a test light - or 12V indication that you're not grounding the injectors when cranking, that would be useful. There is a test procedure for the ECU when you don't have fuel.. And there is a place in the harness (the 90 deg near the plenum) where the 2 injector banks come together. It's a known weak spot of the harness....

Last thing I'd try is disconnecting the ECU. I'd check for continuity between the two injector banks and the injector plugs themselves (only one side will have continuity). No continuity = break in the harness.

downrange383

UPDATE .... I went back to the basics and started all over again with compression check. Cylinder three has 0 compression. Pulled all the plugs and noticed the exhaust valve is stuck open on this cylinder no mater where I rotate the crank. BAD, BAD

Looks like it's back to pulling the motor sometime soon and seeing what the heck went so wrong with this new head.

Thanks to all for your input. Down and out in Virginia.

SoCal4Running

Sorry to hear it.