muddblood

So I am new to Toyotas (and this forum) and I have a 93 4Runner that now won't start. I came out this morning and it started perfect with no issue as it has been for the last 2 months. I got in to drive away and had no power steering (pump leaking). So I added what I thought to be power steering fluid, but in reality, it was brake fluid. I said I can't have that, it'll f up all my seals...and I REALLY don't want to replace a gearbox or lines. So I shut he truck down, drained the fluid from the reservoir through the return hose and put the return hose back on. I got in to head off and the truck would not start. It cranks over great, and it starts for about 3 seconds then dies. It's been doing this all day. I had things to do so I had my dad come over and take me to do my errands. We can back, same thing, crank, runs for 3 seconds and dies. I was able to keep it running with brake cleaner in the air hose, so I know it's a fuel issue. I cracked the supply fuel line and had my dad crank it and fuel came out in all directions so it's getting fuel to the rail.

I did a little research and found out about the circuit off relay and read about how it operates and how to test, but I looked behind the glove box and passenger kick panel and saw no relay. I also read that the MAF (VAM) has a contact that supplies power to the fuel pump once it's sucking in enough air to close that contact, which is what it sounds like to me...and I have read these things go bad quite often.

So....I am wondering why draining my power steering fluid would cause a crank, no start issue?? I know it could be coincidence, but just want t make sure there not some low pressure switch somewhere or some wire I may have bumped loose. Any help would be greatly appreciated as this is my daily driver. Thanks.

Charchee

You have likely pulled off a vacuum line somewhere allowing unmetered air into your intake which might allow the engine to start but immediately die. You can check to see that your fuel pump is running by jumping the FP and B+ pins in the diagnostic connector under the hood. Somebody correct me if I have the wrong pins here. It's been a while since I have had to do this. Jumping these two pins will allow your fuel pump to run without the necessary signal from the MAF. Will the engine run if you give it some gas while starting it and just not idle on it's own or will it not run at all? Where are you spraying brake cleaner into the air intake? Not a real good idea by the way. I can walk you through the whole thing in detail but the first thing you need to do is go around everywhere you had your hands when you were fooling with the PS system and check for any rubber lines you may have moved at all. Just pushing one out of the way with your elbow can be enough to crack an old vacuum line. Also provide us with what might seem to be too many details of how it is behaving like how long it takes for the engine to hit and exactly how long it will try to run before it dies.

Also, go ahead and check your EFI fuse. I believe it's in your fuse box under the hood on your model. It is a 15A fuse on my 89 model but it's in a completely different place on mine and may be a different size on yours.

Those are some basic things to check. The tests will get more complicated after that but I'll go through them all with you if you need me to. These engines are pretty simple so don't go overthinking anything. All engines need air, fuel and spark to run. Always start there and figure out which one you don't have and then troubleshoot the issue. Get the circuit opening relay out of your head for now and use the fuel pump jumper trick to possibly rule out the MAF if you don't find a vacuum leak. You can search the web for information on the FP jumper or I can walk you through it if you need me to.

muddblood

EFI fuse is good as is the EFI relay...even switched it with a fan relay. I read about the fuel pump jumper and I did it a few times when I bought it because it did have a CEL (knock sensor, which has been fixed). No clue if it's throwing any codes as I have not check.

The battery is nice and strong. It only takes maybe 1-2 seconds for he engine to catch, then dies immediately 1-2, sometimes 3 seconds. I took off I believe the PCV breather hose from the valve cover and sprayed brake cleaner in that. I know it's far from ideal. It ran with that, I revved the engine, it ran, then died once the brake cleaner was depleted. Truck won't even idle...if I give it gas while starting, no affect.

Pretty sure I forgot to touch in some of the things you mentioned....ill go back an retread the reply....
I will check vacuum hoses REAL careful tomorrow.

Charchee

If you are getting good fuel pressure up to your rails then it's starting to sound like an injector signal issue. If giving it gas doesn't change anything, your engine may just be hitting for a second off your CSI and then dying when no additional fuel is supplied. For the primary injectors to fire, the ECM needs some feedback from the coil / igniter. You could be having an issue with this signal if your CSI is firing but not the main injectors. I don't want to start making assumptions so just make sure you are getting plenty of fuel up to the rails and double check anything you might have bumped when messing with your PS pump before we go any farther. Also, when you get it running, you need to get ALL of that brake fluid out of your PS system even if you have to flush it several times. It may or may not damage the seals but it will rust everything it touches. A couple flushes should get most of it out. Wash under your hood everywhere it touched as well. That stuff is hell on steel.

muddblood

Good point about washing the brake fluid from the engine bay! I tried unplugging the CSI and it still seemed to not make any difference. I'll check very thoroughly around the PS pump and battery and see if I can find something. I don't have my noid lights here so I can't check injector pulse. If I still get stumped, I'll bum a ride off my dad and get my noid lights.

Not it sure if this helps any, but if I keep the ignition in run, then start, and let it return back to run, it doesn't even try to run. If I turn the ignition back to acc or off, then start, that's when it runs for 1-3 seconds then dies.

Charchee

Now that is interesting. Kind of makes me think of a relay. If a relay were to be failing, removing the signal voltage from it and then resupplying it might make it close the circuit again, for a few seconds until it failed again. I have never seen this before so don't jump to conclusions, but I suppose it could happen. On some of my older freightliners at work, I have seen a similar condition but they use automatic resetting circuit breakers in place of fuses. The breakers will throw after a few seconds when there is a fault in the circuit and will stay thrown until all power to the breaker is removed and then they will reset and work again for a few seconds after that until they throw again. You might probe into your EFI relay circuit and watch the voltage as the engine dies. If you don't lose voltage when it dies, then you can probably rule that out.

ZUK

iTrader: (1)

I think it has something to do with that switch. Try bypassing it. Jumper the 2 related contacts.Not sure which ones right now but a quik google.....

muddblood

Battery dead now and being charged at local parts store. I will check injector pulse and jumper once battery is back in.

I cleaned the engine this morning with engine degreaser and looked around the PS pump and I cannot see any signs of a vacuum leak. I did see 2 vacuum hoses going to the back bottom of the pump up to the intake and one of these had been "repaired" by previous owner but VERY loose fitting at the intake, so I replaced it. I'll provide more info once the battery is back in.

muddblood

No injector pulse. The 15A fuse under the hood is good...not sure how to test the relay or what else it could be.

I have 12VDC at the injectors. I have checked all the grounds I can see and all look good..no grounds around the PS pump.

Did this test too and 0 Ohms on any of the pins mentioned:

Distributor connector using the wire colors on the harness side.

Terminal-1: White..NE signal
Terminal-2: Red..G1 signal
Terminal-3: Black..G2 signal
Terminal-4: Green..G- signal

Between G- and G1, it should be 125 & 200 ohms. Between G- and G2, it
should also be 125 to 200 ohms. Between G- and NE, it should 155 to 250
ohms

Charchee

Did you test the distributor side or the harness side? The description of the test is worded a little funny. The way I read it you would be testing the distributor side of the circuit using the wire colors on the harness side only to determine what pin to test. I have never done this test before so I'm not sure but that's how I read the above description.

muddblood

Oh shoot....I checked the harness side. Thanks for pointing out that the article is worded a little funny...I understand now. I'll check the distributor side tomorrow. I'll report back with my findings....

Charchee

They probably worded it that way due to the possibility of a vehicle having an aftermarket distributor on it with different colored wires.

muddblood

Gotcha! Thank all of you for the help thus far! I REALLY appreciate it!!!!

muddblood

Ok....so checking the distributor the CORRECT way, it checks out....

Between G- and G1 - 149
Between G- and G2 - 149
Between G- and NE - 189

Numbers look to be right in the middle:
Between G- and G1, it should be 125 & 200 ohms. Between G- and G2, it
should also be 125 to 200 ohms. Between G- and NE, it should 155 to 250
ohms.

This info came from pirate 4x4.com (http://www.pirate4x4.com/forum/toyota-truck-4runner/980033-3-0-injectors-wont-fire.html#/topics/980033?_k=qjgisg) so not sure how accurate it is.

Charchee

It's going to be the igniter that will ultimately send the signal for the ecm to send the ground pulse signal to the injectors. This thread should help you out.

https://www.yotatech.com/forums/f2/n...89-95-a-10543/

RJR

Did you put the air intake and the VAFM meter all back together after reworking the power steering pump? Your original symptoms are exactly consistent with not having the VAFM plumbing and/or electrical connections connected. The fuel pump will run for the few seconds that the starter is cranking, and then stop running as soon as the key is released, causing the engine to die within a couple of seconds.

You can jumper FP to B+ in the diag connector to bypass the VAFM circuit, but my guess is once you reattach all the intake plumbing and the electrical connector to the VAFM it will fire and up run just fine.

The igniter is difficult to diagnose without special knowledge and equipment, and my guess is there's nothing wrong with it anyway, especially since the engine will run briefly and/or with starter fluid in the air intake.

muddblood

Air box is on the opposite side of the power steering pump. I did jumper FP and B+ and no affect...assuming of course I had the right pins in the DLC. But yes, I did check all those connections. My understanding though, is that the VAFM controls the fuel pump and not the injector pulse, correct?? I suspect a broken wire that runs in the harness that is behind the PS pump...

The article also has a procedure to check the ignitor so I will try to follow that. I believe that very same article someone commented about a ground crimp that goes bad in the harness that runs over the top of the engine. And I know I moved that harness some messing with the PS pump.

Charchee

Looking back over the thread, I don't see anything about the outcome of jumpering the fuel pump. That is a must in any no start situation. I assumed that had already been ruled out.

The engine will run for a second or two off the fuel from the cold start injector. He said it wasn't getting the negative pulse signal to the injectors so the igniter would be my next test subject but, not until you have absolutely ruled out a fuel rail supply issue.

muddblood

My apologies. I DID jumper some pins and no affect. It's kind of hard to find correct info, but here is the pic I used (top of this post). I went out just now and verified with the pin chart on the inside cover of the DLC and I did jumper the correct pins.

Charchee

I figured you did but just checking. Now you said no effect. Did you not notice that your fuel pump turned on when you installed the jumper. You should have heard it at the tank and could probably hear it flowing through the pressure regulator. I just want to be sure that we can rule out a fuel supply issue. What method did you use to test for the negative injector pulse?