1989 Truck with a 5VZ-FE. First motor and ECU were from a 97 4Runner. Hydrolocked it first time out wheeling :*(

Bought a 98 auto motor (truck is a stick, just threw a couple auto tranny codes but it ran fine). I did not realize the 98 harness was different, so I just plugged it into my 97 ECU. Would not start. Realized harness was different, so I swapped the 97 harness in. But it still will not start. Possible I fried the ECU? Getting fuel and spark, and no OBD2 codes other than the 2 usual tranny codes..... Ideas please?

 

possibly grounds. If you havent already I would double or triple check and make sure you have good grounds.

 

Its turning over, and occasionally you can hear it fire, but it wont start. I will check grounds now.....

 

Fooled around with grounds, didnt seem to do anything.

I can pull OBD2 codes etc - any chance the ECU is dead from being attached to that 98 harness that is wired differently?

 

I'd ask TMZ on here. He seems to be the most knowledgeable about wiring harnesses and ECUs.

 

I sent him a PM.....

 

Is the MAF fried from when you hydro locked it? Possiblity of the ECU being fried but there was another member on here that used a different ecu and harness and everything turned out ok after he rewired the harness. So I would say that its a slim possibility. If you got a significant amount of water into your intake I would say it would take out the MAF. Without the MAF you truck isnt going to run

 

Yeah, i was just thinking about that. found the resistance values, gonna run down and test it right now.....

 

OK, tested per SF28 Toyota document..... Said to check between THA and E2 for resistance - my volt meter had no reading whatsoever for resistance between the two terminals - not 0.00 - just nothing. No reading.

Plugged maf in, tapped VG and E2G, read 1.9V, when I blew thru the MAF it went to 0v or below? Guessing its the MAF, as voltage should climb, not dip, correct?

 

No reading=open circuit. I'd say your MAF is done.

 

Awesome. Gonna hit up a junkyard tomorrow for one Thanks fellas! Will post with my findings!

 

My posts are not necessarily based in fact, truth, or reality. Take what I say with a grain of salt.

But it's still my guess. If you touch the probes on your meter together, you should get 0.00 as a reading. If you don't, you get a blank screen. Same goes if you probe those two connectors. No reading=open.

 

Yes, if the probes touch nothing, blank screen. Touch eachother, 0. I am pretty sure its the MAF. Worse case, $35 out the door, and I know its not the MAF

 

Even with a bad maf normally it will start up and shut right down. You need to check and see if it is getting fire. Don't go by how it sounds. Without repinning the harness it is a good chance that the ecu will be damaged when plugging the ecu into the wrong year harness. Check the 7.5amp ign and 15amp efi fuses.

 

Ended up being a crank position sensor! Even though I checked resistance.... Guess it must have gone bad sitting at junkyard?