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To make a long story short. Toyhouse broke down in North Carolina. Got towed into shop, shop had it for 4 days. could not fix. On Friday, I said that's it, I'm out of time and money, so I rented a U-Haul and Dolly and towed it back to Ohio (700 miles).

TOWING INFO -
Tell U-Haul its a 88 Toyota Pickup super cab. Don't use the transporter (the trailer) - You need the dolly. Tow it with at least a 14ft U-Haul truck. Has plenty of power, towed good, got about 8 MPG.

Inflate the air bags to 100psi to get the back end up as high as it will go. You need to get the ,back end up as high as it will go. I'm not sure how you would do this if you don't have air bags.

When towin with the dolly, watch out for any steep curbs or driveways. I'd stick to large truckstops for your fuel stops. Remember a large turning radius, no sharp turns, and no backing up, so plan ahead, don't get booby trapped into dead end or small turning radius places.


Troubleshooting Info

I use jumper to bypass fuel cutout relay. Makes it so the fuel pump runs all the time. This should be the very first thing to do in the troubleshooting process.

Fuel pressure regulator replaced, fuel filter replaced, Mass Airflow sensor replaced.

I've checked everything I can think of. Anyone have any ideas?

(I just ordered an ECM off of E-Bay)

John Mc

88 Dolphin 4 Auto

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Sorry John, I'm in NC. You could have crashed at my place. The newer systems are out of my area. Glad you made it back home.

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Trouble shooting aid. A Noid Light set ($20 Ebay) They check the power to the injectors.

An ECM sounds like a good idea at this point. A fuel pressure gauge is a good thing too.

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Linda, et al;

It will start, run for a second then die.

Here is what has been done:

Carefully inspect for vacuum hose cracks / breaks, intake hose cracks / broken (about a bazillion times)

Jumper test connector to bypass Circuit Open Relay and ECM control of Fuel pump.

Fuel Filter and Regulator been replaced.

Good flow of fuel returning to tank (regulator return, so know pump is doing good job)

Replaced Mass Flow sensor ( I don't think there was anything wrong, but shop replaced)

Fuel Injector ground connections on intake manifold reworked (brown wires)

Good spray pattern and quantity on cold start injector. (remove from plenum and observed)

Throttle position sensor OK.

Voltage checks at ECM appear normal, sensor inputs, ignition inputs

If I squirt carb cleaner in the throttle body, it will start and run, as long as I keep squirting carb cleaner. (i.e. its not getting fuel)

Two observations

1) LIMP MODE - jump fuel pump and remove mass flow sensor. starts and idles OK. This test basic fuel, ignition circuits.

2) Has run twice. Wierd, on two occasions over hte last week, it started, ran great, no problems. shut it off, would not restart,- back to the same problem.

At this point, the only thing in the control circuits that hasn't been replaced is the ECM. I just bought one on E-bay..

This has several Toyota mechanics stumped.......

John Mc

88 Dolphin 4 Auto





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John it needs about 35 psi to run it is hard to tell pressure by flow I would suggest a fuel pressure gauge test. The start injector will give it enough fuel to start because it is not controlled it just dumps fuel so pressure is not that critical. Remove the air intake to the air flow sensor and push the blade with your finger with the key on that should start the pump. Any air leak between the throttle body and the air flow sensor will cause issues check the rubber joints and the plastic tube for cracks..

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Tank is out, new pump is on order.

The tank came out very easy. about 30 minute job after the gas was drained.

I disconnected the supply line and ran the pump to get the fuel out of the tank. It had a good stream, so I'm not betting money on it being the pump.

The inside of the tank was very clean, (like new). the sock filter was absolutely clean.

I did find the source of occasional gas smell right after fill up. it was the connection where the filler hose connects to the fuel tank. very loose.

I'll replace the filler and vent hoses when I put it back together.

John Mc

88 Dolphin 4 Auto

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Good fuel flow AFTER the pressure regulator should mean good pressure. Especially with a new regulator.

The injectors are batch fired 1&3, 2&4. Signal comes direct from ECM, no connectors.

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When I get the new pump installed, I'll do a timed fill . i.e. on the return line, see how long it takes to fill a 1 pint container. I had flow on the return line, but nothing to compare it to. I would guess there was more than enough to run the engine.

JOhn Mc

88 Dolphin 4 Auto

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Hi John

I can't offer any advice on your non running issue, just encouragement! if anyone can figure this problem out, "you be de man" good luck with this and I'll read your follow up posts with interest, must say you had an ingenious way of getting your rig home, one question, I believe you have an Auto trans too, towing like that, do you have to remove the drive shaft?

Mike

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Mike,

Thanks, We've been thru all the easy and obvious stuff, so now its almost down to simply guessing and throwing a couple more parts at it (Fuel pump and ECM)

As for towing, if you have an Auto, if you were towing a short distance, a couple miles, and at slow speeds, I would say your OK. Think about the thread on this forum regarding the aft transmission bearing. The engine must be running to lubricate these bearings, and the rest of the tranny.

YES - You MUST remove the drive shaft. This takes about 15 minutes, need 2 14mm wrenches. The drive shaft is split, so its easy to just remove the aft shaft on both ends.

John Mc

88 Dolphin 4 Auto

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Replaced the fuel pump. there was no difference. Putting the tank back in is a real pain in the butt, mainly getting the hoses to connect to the tank.


The truck started and ran great, I drove it for about 15 minutes. However, when I shut it off, It reverted back to the same problem again, it would start, then stall out.

ECM - I bought an ECM on E-bay for $60, match the part number with my original ECM.

The truck started, and drove OK, I shut it off, and it restarted OK. I've since restarted it 15 -20 times, and it has started every time. This is starting to look promising. I'm getting the courage to take it to the gas station for gas, and shut it off.

John Mc

88 Dolphin 4 Auto



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Replaced the fuel pump. there was no difference. Putting the tank back in is a real pain in the butt, mainly getting the hoses to connect to the tank.

The truck started and ran great, I drove it for about 15 minutes. However, when I shut it off, It reverted back to the same problem again, it would start, then stall out.

ECM - I bought an ECM on E-bay for $60, match the part number with my original ECM.

The truck started, and drove OK, I shut it off, and it restarted OK. I've since restarted it 15 -20 times, and it has started every time. This is starting to look promising. I'm getting the courage to take it to the gas station for gas, and shut it off.

John Mc

88 Dolphin 4 Auto

Good luck John hope that is the cure!

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Throttle Position check OK, voltage measurement on the ECM, all were in the normal range The Factory Service Manual has a very good troubleshooting section that includes how to test components, and also normal readings you should see in the different sensors and ECM.

I drove around today, got brave and shut it off for gas, restaurant, store, etc. it restated no problems. ran with no problems.

It looks like the problem was the ECM. This is very unusual and stumped several long time Toyota people.

With that said, If you ever have a similar problem, there are a lot more common faults that will cause this problem. The most common in order of cost/probability from Toyota techs;

1) broken, air leak, intake hose or vacuum hose.

2) EGR stuck open, leaking

3) Brown Injector electrical ground return wires on Intake manifold - corroded, bad connections.
4) Cutoff Relay not turning on fuel pump. Can be bypassed on test connector.

5) ECM power relay.
6) Mass flow sensor - (not turning on fuel pump, again, this can be bypassed at test connector.

7) Fuel filter blockage
8) Fuel pump defective
9) Fuel Pressure Regulator

John Mc

88 Dolphin 4 Auto


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