racerr900

I have a 1989 Toyota pickup. I recently swapped my 88 motor into the 89 truck. It ran fine for 4 days and on the fourth night it just shut off on me on my way home from from work. Now it will start up and shut off immediately. I checked all relays, fuses, new fuel filter, and replaced the ignition switch. I used a fuel pressure guage and I have 34 pounds of pressure before the fuel filter. I also have pressure returning through the return line. I even swapped out the fuel pressure regulator from my 89 motor. After I was convinced it was the ignition switch I replaced it and it does the same thing. I am still thinking the fuel pump. It might have had 34 lbs of pressure, but loses after it starts up. I also ran a hot wire straight to the fuel pump to eliminate any electrical troubleshooting with the fuel pump. I have a Haynes manual with wiring diagram I have been using to check with my multi meter and all electrical is checking out OK. Oh yeah, I ran the truck with starting fluid directly into the intake and it ran fine, so I am thinking it is a fuel problem. Any help would be greatly appreciated! I am stuck, and I am too stubborn to take it somewhere and get bent over for a diagnostic!

Waterboy

Mine would do the same thing when I had the intake tube pulled off. The truck can't figure out what to do with all of the air when the MAF says it's not getting any. Maybe try checking all of your intake pipes. Sorry I don't have any better ideas. Good luck.

DeathCougar

iTrader: (23)

Airflow meter, definetly. Just like waterboy says, the ECU does not know what to do with all the air so it just shuts it off the fuel. Thats why it will run when you spray starter fluid down the tubes. The engine is now getting all the necesary ingredients: Air, FUEL, and Spark. Check wiring connections around your Airflow meter, and throttle position sensor. Those two main components are most likely the cause of your problem.

racerr900

[There was one thing different on the 88 motor I installed that was not on the 89 motor I pulled. just under the intake on the 88 there is something called an air switch. It has a two pin wire connector, and the 89 motor did not have one. I read about it in the Haynes manual. I don't think my motor swap had anything to do with the problem, or else it would not have ran for those four days. It ran good, just like it did in my 88 truck, except for this 89 is in better shape than the 88. Sad part is I junked the 88 shell the day before this one quit.

racerr900

hey guys thanks for the input so far, but the air flow sensor is not the problem, I tested it with a ohm meter and it checks out according to specs. I even switched it with an extra one I have and it still did the same thing. I am going to try a fuel pressure guage again and make sure I am getting constant pressure. I am borrowing a diagnostic scanner off a friend to see if anything will come up on the computer.

Unhappy99

34 psi fuel pressure is way too low. Should be ~40psi, and not drop. Even a Haynes manual should have this spec. Replace fuel pump, or find the clog.

If I recall correctly, you can get to the fuel pump through the cover underneath the passenger rear seat, thus not having to drain and drop the tank.

racerr900

Unhappy, that sounds good--unfortunately I have the pickup not Forerunner, so I have to drop the tank. Thats OK, cause I had it dropped once, I will do it again. The fuel pump is the only logical thing to point fingers at now that I have tested everything electrical. And that is the only thing I can think of that would just up and quit while I am driving it. If there was a problem with my motor swap it would not have worked from day one. Once again, I appreciate all the input and will let you guys know what comes out of this mess.

Oh yeah, anyone need advice on 2 stroke dirt bike and quad motors, I am pretty good with that!!

Kevin

racerr900

I checked the Haynes manual, and Unhappy was right, my 89 calls for 38-44 pounds with the ignition switch on, engine off. I am using an 88 motor though which calls for 33-38 pounds with ignition switch on, engine off. I am using the 88 motor with everything else 89. So I figure the specs should go according to the 89. I am going to put the fuel pressure guage on again and double check my pressure. I had a friend do it last time and he told me 34 when cranking--he did not measure with the ignition on, engine off.