mmjohnston

Im looking for any suggestions, I bought a 89 toyota 3vze was running and driving then just quit is what im told...... Now i have read forums and tech help colums for a week straight before i joined here. It has new distributor tests good, I have spark at the plug after i replaced ecu with new used one, it fires up for a 1/2 second then dies found out that this is because its running on the cold start valve if i unplug it it wont fire at all.. doesnt seem that injectors are squirting fuel. Ive jumped the Fp and B+ no luck. Have been reading about various water temp senders/ switches and cant figure out if they could tell the ecu not to pulse injectors?

rattlewagon

Any check engine codes? Even if the light isnt on there my still be getting a code.

Is the fuel pump coming on? If you squirt gas in the intake will it fire? If you crack open the line going into the fuel rail, is it getting gas there?

Welcome to the forum!

scope103

"runs for 1/2 second then dies" is the classic symptom of a COR/VAF problem. You correctly identified jumpering FP to B+ as the test, but "no luck" isn't much of a result of that test! You should have been able to hear the pump running with jumper in, key on, engine off.

If that isn't it, you should check to see whether the injectors are opening BEFORE you start thinking of reasons "why" they aren't opening. You should be able to hear the injectors clicking (since you may be doing this while cranking, you may need a real stethoscope http://www.harborfreight.com/mechani...ope-69913.html instead of just the tube inside a roll of paper towels). If you can't hear clicking, then you'll want to check for pulse, and the easy way to do that is with a "noid" light. (You make your own from an LED and resistor to save about $25. Remember that LEDs are polarized.)

mmjohnston

OK ill try the noid tester, No engine codes / just flashes forever have tons of fuel pressure at the rail (pulled regulator). Fuel pump kicks on with it jumped and also on its own through Ignition on and open flap door in air box. Yes it runs if i spray either or something in the intake stops as soon as i do. Also tried replacing ignitor, coil, 2 ecu's first one had no spark second one has spark, distributer, efi relay, checked ground locations one is missing behind intake to fire wall it has the half to the firewall but other half to intake is missing. after looking at other 3vze engines ive notices that it bolts to a nice clean machined surface on the back of intake, well mine does not have that. So i made a temp ground to fenderwell to intake bolt instead. tested and i have ground.

scope103

There should be a ground wire to the aft cam bearing cap on the passenger side. The injectors are all "switched ground" (the hot side is at 12v with key-on, and the ground side is switched by the ECU), so the important ground is the one the ECU goes to, which is the bearing cap.

The ground wire to the top of the plenum doesn't really do much.

Good luck.

mmjohnston

OK Im back and have tested with the NOID light. Here's the kicker I pulled the injector plug from the one just under the fuel pressure regulator easy to get to. So i have my wife turn the key with the noid light attached and it fires up and runs!!!!! a bit rough but it runs!!WTF I say!!! so when i plug it back in i instantly kills the engine. said plug has injector pulse signal and flashes when runnning but if its clipped onto injector it will not start. does this mean its bad injector?

scope103

Could be. But first, check the resistance of the injector. http://personal.utulsa.edu/~nathan-b...90injector.pdf Should be 13.4-14.2 ohms (as if you could measure it to that resolution!) IF your vehicle does not have the big ballast resistor on the inner fender (I think that ended in 1986, but I don't have the figures). If you don't have the resistor, you can connect the injector directly to 12v to see if you can hear it open (DON'T do that if you think it's shorted; you could have some fireworks using a car battery into a short)

Another possibility is a short in your harness; wiggling it opened the short and let it run. Be systematic.

RJR

Sure sounds like the injector is shorted, but measuring the resistance as scope suggests will tell you for sure.

mmjohnston

Ok yes that injector tests bad. Seems odd that it would short the whole system for one bad injector. Will be replacing this weekend hope it works! Thanks for all the help

mmjohnston

Replaced injector Fired right up. Only one was bad or shorted and kept it from running. strange. Anyways Thanks again for all Help.

RJR

Glad it's now working. Given that all of the injectors in a bank of 3 are wired in parallel, it makes sense that one bad one could shut down the whole bank. Unusual, but it looks like you were "lucky". Next stop, the lottery!:-)