I have an 88 4runner with a 3.0 V6. When I got the truck it was not running, but the owner said it was running when he parked it 3 years ago. After a little testing I realized the fuel pump was bad. I replaced it along with in-line filter and all of the lines to/from the engine (return, vent, and supply). I tried to start it, but no go. It is trying to start. It fires up for about 1.5 seconds, then just it just turns over. If I turn it off and then back on it will fire up for another 1.5 seconds then nothing.
I checked the spark and it is good, so I pulled off the intake hose and sprayed starter fluid in. It started. To me that means that I am not getting fuel. I know it's not the fuel pump, because I checked with the jumper and verified that it comes on with the ign key as well.
I checked the fuel pressure at the pressure regulator. It's good.
I checked the pressure at the cold start injector. It's good.
I checked the ohms on the cold start injector. It's good
I checked the EFI fuses under the hood and drivers kick panel. They are good
I checked the relay just above the ECU (open relay) with the ohm meter.

Basically it seems like the injectors are not squirting fuel, which means they are not getting a signal from the ECU to squirt. I have come to the end of my mechanicing knowledge. I am a carb guy that is used to V8s. This EFI thing has a lot of variables that can go wrong. I could really use some advice on what to check next. It has to be some kind of sensor or something, it seems like.

Or, if someone is in Albuquerque and wants a beer and some pizza let me know. I have the tools, but I could really use some advice.

Ben

 

use a noid light and check for injector pulse. also the airflow meter controls the fuel pump. if u leave the fuel pump terminals jumpered will it run?

 

Tried the fuel pump jumper while starting, no luck. I also, pulled the plug on the fuel pump to see if it was getting juice during ignition. It was good.

I don't know what a noid light is. This whole fuel injection thing is new to me. Is that a special light or is it something I can fabricate?

 

Is the dummy light on? and not sure but like desert said if the air flow meter is unpluged or not hooked up it will not start.

 

I googled the "noid light" and I am on my way to Pep Boys to pick one up.

 

Mine was doing the same thing, hadnt ran in 3 or 4 years and I got it to the point of it being able to fire for a sec or so. The culprit ended up being the circuit opening relay and making sure all your intake hoses are sealed and its only pulling air through the airbox. I had checked my co relay also, thought it was still good. The only way I could tell that it wasnt working was when trying to start it, I couldnt hear the relay click like they do when they're working. I would double check those areas well.

 

Yotamonsta - If dummy light means engine light, the answer is no it's not on. I actually thought that was a little wierd. I thought the engine light came on when you turn the ignition key to start. No matter what position the key is in, it never comes on.

Yota Guy - I checked the circuit opening relay, I think. That is the one by the pass kick panel, correct? If so, I put my head by it while my girlfriend turned the key and it clicked like it worked.

I am just about to try the roid light.

 

huummm maybe it been unhooked? anyways pull a spark plug and see if they have gas on them...you did say that you was getting fire right?

 

I just pulled a spark plug and it was wet. There goes my first guess. Apparently the fuel injectors are working.

 

Was it getting spark?

 

I just pulled 2 plugs and it had a good strong spark. If it's getting spark and the plugs are wet, it should be starting....right? I'm going to pull the rest of the plugs and check them. If you have any more ideas....shoot em' at me. I am going to try the noid light here in a few, but it seems that if the plugs are wet that means the injectors are working. I am assuming that, since I know fuel injection very well.

 

You said it was getting spark but did you test that at the sparkplug level or higher up?

My only other guess, though seemingly silly, is maybe the idle speed is too low, sending gas to your chambers but not enough to burn?

 

chances are that the gas has gone bad after sitting for 3 years, along with the rest of the fluids in the truck. If you havent done so you need to drain the gas tank and fill it and the lines with fresh gas. Either drop the tank to empty it or try siphoning it the fuel out with a hose. Moisture will form as your lubricants break down so you need to change diff fluids, transfer case, tranny, ENGINE OIL, coolant

 

I pulled the actual spark plugs and grounded them out. Is that what you mean?

I've tried holding the gas in a little to increase the idle, but nothing.

This does make me think, though. What does an engine act like when the fuel pressure regulator is going bad?

 

Spenc - I drained the fuel tank and filled it with new fuel when I got it. I thought the same thing.

 

Yeah, clean the spark plug off and look for spark with a "spark tester" or try grounding it within a 1/2 inch of ground to look for spark.

 

if it been sitting for three year i would replace the spark plugs anyways but thats just me they are only 3 buck each or so.....then you can elminate that....distributor cap and rotor is like ten buck and that would solve the spark problem!!! I woulD think it might be a sensor on the intake check all the wires and make sure they are not bare or broke and of course make sure it pluged in and hooked up to your intake or it will not start....

 

Make sure you are not getting suction at your gas tank. Try removing your gas cap. This is likey not the problem, but I found a clogged "vent line" on my 4runs and it helped. Also I have heard of this causing dying issues after running for a period of several minutes. There is enough suction that the pump cannot provide enough fuel to the injectors, thus killing the motor. Worth a shot, its easy and eliminates another possibility. Good luck.

 

Yotamonsta - I just got back from the store with a new set of plugs and rotor. I'll have it on in a few minutes. Parts are so cheap for this thing.

Krytellan - I'll test these new plugs to see if everything works for sure

ehertz - I disconnected the vent on the top of the tank and checked to see if it was clear into the tank, but even with the hose disconnected it wouldn't start. I actually replaced the vent line and supply line a couple of days ago. I was thinking the same as you.

 

Ok fellas, I just ran used the noid light. The only injector that was working was the cold start injector up on the top. I checked 2 injectors on the engine and the cold start injector. What does that mean?

The ECU sends the signal to the cold start injectors, correct? Why would it not send a signal to the regular injectors?