Hello! New user here, glad to have this website resource available!

I'm trying to diagnose a crank no start on a 1994 4x4 3VZE. Its been broken down for a few years after a broken timing belt and near simultaneous fuel pump failure, although I may have messed up the fuel pump after the timing belt by crossing a wire.

I've got it back together and it cranks and tries to catch but won't quite make it. It will run a few seconds if I manually spray gas down the intake throat. It was throwing code 12 so I ran a second ground wire from the injector manifold to the fire wall and that cleared in, no codes.

My question is, with FP and B+ jumpered I can hear the new fuel pump run and also I hear what sounds like constant running fuel under the plenum. Is this normal? I figured the fuel pump would prime the injector manifold pressure then the sound would stop but it doesn't. I smell a faint gas smell but I think that is the cold start injector constantly firing, if I let it sit with the fuel pump running a few minutes a small amount of gas will leak from inside the plenum and trickle down the intake throat. Is that normal? Truck is on a slight angle so intake throat is at a low point allowing gas to dribble down.

Thanks for any help this project has gone to long with too many breaks and now I'm kind of stuck. All signs point to fuel delivery being the culprit but my gut tells me I have something cross wired or a mix up in the hoses somewhere.

 

Yes. The fuel pump runs when the key is turned to STArt, and continues to run once you're pulling air through the VAF. When the pump is running, the FPR is constantly recycling fuel through the return line to maintain rail pressure.

It better not be. The CSI should only open, for a few seconds, during cranking, and even then only when cold. This is easy to test; remove the CSI from the plenum (don't disconnect the fuel line; you'll have to replace the crush washers) and run the fuel pump with the FP jumper. No fuel should come out of the CSI.

No. If you have a leaking injector (CSI or regular), you'll flood the engine and it won't start. If you get enough for fuel to trickle out, you could even hydrolock the engine.

Another source of "gas smell" is the Fuel Pressure Damper at the aft end of the right fuel rail. It has a rubber diaphragm that will fail after 20 years. Slow leak, but in a dangerous location.

 

Ok would the check for this be to remove the plenum then jumper the fuel pump while observing the fuel rails for leaks?

I have already removed the banjo nut from the cold start injector, there was no crush washer that I could see. The crush washer is copper, correct? It only has a regular washer that sits between the hollow bolt and the banjo nut. It doesn't leak from the outside but maybe is leaking into the plenum and is the source of the gas smell?

I thought I had the issue licked today (for about the 8th time) when the gas that sprayed out the disconnected banjo nut was a bright gatorade green. I figured this was bad gas from sitting so I used the fuel pump to drain it all and replaced with fresh gas. Still crank no start although it does kick a bit.

I'm trying to run down all the possibilities before I take the timing cover off again and check to be sure my cam timing marks on the belt will line up.

On the subject of that and the timing belt replacement: my engine doesn't have a spring loaded timing belt tensioner like others I've seen. Its not just missing the spring, it appears to have never had one as the mounts for the spring isn't there. Engine has a "51" sticker on it if that helps.

 

Oops I meant the cam timing marks on the plastic cam gears. I am correct in thinking that if I rotate the engine enough times by hand the marks on the cam gears will line up same as I did when I put the new timing belt on? I am fairly sure I did that job correctly but it was my first time so maybe not.

 

Plastic cam gears???

 

Ok doing research and it appears there should be 2 crush washers but only one when I removed the banjo nut. A missing washer causing a no start condition? Just crazy enough to be true, especially since it prevents fuel leaks apparently. So far no luck tracking these down using "23801H" as a part number, which is how its notated on the exploded diagram I found. Could this really be my problem? Since I've thought I'd figured it out several times already I am cautiously optimistic.

Anyone got a NAPA or Advanced Auto parts part number for these? Do I have to go to the dealership to find them?

 

What is the proper name for the white gears the timing belt engages under the timing belt cover? I remember them as being white plastic but maybe I'm mistaken.

 

Ok I looked it up "camshaft timing sprocket" you are right metal not plastic. I feel dumb they would have to be metal no idea why I remember them as being plastic.

 

The '94 has a hydraulic timing belt tensioner. No spring. https://web.archive.org/web/20120405...67timingbe.pdf In theory, you could turn the belt enough times for the marks on the belt to line up again, but it's a lot of turns and you don't care. All you care about is whether the marks on the cam sprockets and the crankshaft all come to the top at the same time (the crankshaft turns twice for each turn of the cams)

One easy test to try is to replace the FPR return line with a piece of 6mm / 1/4" clear vinyl to a suitable container. Then run the pump with your jumper. There is no spec, but I get about 1/2 liter/min. If you get a lot less, your pump may be unable to keep up.

Testing for leaks at the Damper is pretty easy; just wipe it with some brown paper towel (gasoline evaporates so quickly that it might not feel "wet" on your fingers). Testing around the injectors would require removing the plenum, which would require doing something with the FPR return line.

 

Ok thanks I'll bump this thread when I find parts and when the snow that fell last night melts. Pinning my hopes on "not enough fuel pressure to manifold due to missing washer allowing leak into plenum" for now.

Sourcing this washer locally has been a pain in the ass, anyone got a NAPA part number?

 

I've only been able to find the crush washers at the dealer, but even there they're cheaper than dirt. Do yourself a favor, get two more in each size you plan to replace. They have a charming habit of popping out of your hand and rolling into the grass.