Charchee

I think you may need to troubleshoot your ECM. My favorite way is to get your hands on a working ECM from a junk yard or a buddy's truck and plug it in. If you don't have this option,You need to check for power at the ecm. Check the fuse and circuit opening relay. The last time this same issue happened to me, I was in a hurry and swapped my ECM with my spare and haven't had any issues since. I know I cheated but I needed to get my truck home. It sounds like you aren't getting your ECM signal to your injectors and with the other parts of the system having been replaced, start trying to rule out the ECM.

scope103

Are you absolutely sure that you are not out 180° on ignition timing? (your plugs are firing at the top of the exhaust stroke instead of top of compression stroke) A timing light will read the same in either case, but it won't run if the timing is that far out. Pull the upper timing cover. When the cam sprockets are pointing straight up (the arrow), check that the distributor is pointing at #1 (actually, about 10° past #1, but what you care about is that it isn't 180° away).

If you think you have spark in the right place, give it a little squirt of starting fluid (on the 3ZVE there is a line from the left valve cover to the induction tube; you can squirt it in there). If it fires with that, you have a fuel problem. If it doesn't fire at all, I suspect spark.

robertd33

Grabbit89 you've put a lot of work in!

i saw that you have the FSM... excellent!
(procedure to set the timing is on EG2-26)
jump TE1 & E1
idle 800
timing light should hit 10°
remove jumper & timing should be 8°
verify advancing but revving the engine & timing should go up/down with speed.

i would:
check timing belt for correct install
check for spark at each plug
spray starting fluid while cranking

you still have NO fire at all?

Grabbit89

I guess I could try that. I don't have an extra one though so I might have to hunt one down. The only thing that makes me think it's not the ECM is that I get noid lights to light up at each injector plug while cranking, spark at each plug while cranking, cold start injector sprays for a second at initial crank and I even got the code for the TP sensor when it wasn't plugged in. Now I get the constant flash of the check engine light indicating no codes.

I still have the upper timing belt cover off. Timing belt is dead on. I pulled the cap and it points to cyl 1 (straight up) at TDC. I'll double check it though. I did try using starting fluid with no luck. Not even a hint of firing.

tinse4

Now I am new to the 3.0 also. I had to do the top end of mine due to the head gasket going out. I found while testing and starting mine that the air cleaner and ducting had to be in place. I believe it is due to a sensor sensing the vacuum of the engine. Mine would turn over for days, but never start without the air cleaner hooked up. This my be way off but thought it is worth a shot.

scope103

Absolutely. This is true for all fuel injected engines; the ECM needs to know how much air is coming in to set the open-time on the injectors. The sensor in this vehicle is the VAF (vane air flow meter) sitting above the air cleaner.

Charchee

I'm scratching my head. If your valve timing is correct or even close and you have spark at the plugs you should be able to get a hit on starting fluid. The only thing I can think of would be that your ignition timing could be bad off causing the spark to come after the pistons have already pushed the starting fluid on out of the exhaust valves. I'm sure you have your plug wires located correctly. I have to say that if I had spark but no fire on starting fluid, I'd be looking at my distributor.

Grabbit89

Intake tubing is in place. I'm used to the old vw mechanical fuel injection units that won't work unless there is vacuum pulling on the fuel distributor plate.

I also checked the Airflow sensor, moves freely.....

Charchee

If you jump the FP and B+ terminals in your diagnostic connector, you will signal your fuel pump to run regardless of input from your MAF sensor. You might try that in order to rule out or rule in your MAF as an issue. If it runs jumpered, you may need to replace or at least troubleshoot your MAF. If you jumper these terminals and turn the key to run, you should hear fuel moving through the system and also hear you pump running. If you don't hear anything then your fuel pump isn't working for one reason or another.

scope103

Charchee is right; with a tiny bit of starter fluid, the engine should at least fire no matter what the fuel system (pump, VAF, COR, regulator, injectors, etc.) is doing. So if you have confirmed spark and a little starting fluid without any firing, what else could it be? I already suggested that the plugs might be firing in completely the wrong place (time). I guess another possibility is "no" compression at all -- it will be easy to put a compression gauge on it to rule out that possibility.

Charchee

It's got to be ignition timing. Starting fluid doesn't even need to be compressed to fire off. I would think an engine with no rings on the pistons would give you some hint of combustion. Start troubleshooting your distributor.

tinse4

You might try a leak down test. If the valves aren't seating from sitting a while, or debris in them you wont get compression either. You said your brother inlaw was having idle and starting issues also. When I put mine back together I had to send my heads back to the shop being they didnt clean them right after reworking them. I had half of the valves hung open from debris. Just a thought.

Walt Weber

I know it's an old thread but I'm having the same issue. except I can get mine to fire bit only when I take the distributor bolt all the way out n turning it counter clock wise alot... it fires but definatly not rite.i triple checked the timing, good plugs n wires, have spark but I would consider it a lil weak, injectors r all firing,did a compression test n I have 5 cylinders at 180 psi n 1 at 175 psi, I checked valve clearances n all check out good

my research lead me to thinking it's the ignitor

scope103

Hard to believe that those two statements are simultaneously correct.

If the distributor gear is off one tooth when installed, timing will be off by about 28°. That could explain your first observation. Some have reported that with our vintage trucks, the annular rubber ring in the harmonic balancer can fail. The outer ring (with the timing mark) will rotate on the inner part (connected to the crankshaft). So the mark can say "TDC" even though the crank is not at that position. That would explain your second observation. You can check that by "feeling" for TDC in #1 with a straw or chopstick (don't use a metal screwdriver; too easy to scar something) as you rock the crank.

Igniter would be way down my list. Hard to think of an igniter failure that would cause weak spark, and yours is enough to fire the engine when the timing gets close. Plus, it's not a cheap part.

Send_help

I know this thread is around 5 years old but I am just about at my wits end and this is my last hope. It’s 4 am and I’m still relatively new to this truck and I’ve scrambled the forums. My truck is getting spark, fuel and I’m not so sure about air. I’m doing my best to see if I can diagnose the problem before dumping money into it. The truck was running strong for months but randomly cut off while turning a corner on my way to work. Everything is telling me this issue has to be simple but I have yet to figure it out. Any and I mean ANY information would be appreciated.

itzguamdoe

any findings??? I too am dealing with this was driving fine then died while turning right into a parking lot. 95 4runner 3.0 5 spd. Cranks for days but won’t run.