96 5sfe won't rev past 3k-FIXED Options

[two55309]

OK a little bit a history first. 1996 celica with a 5sfe 2.2. brother in law threw a rod in the car gave it to me. Replaced the engine with a 3sfe block and used everything else from the 5sfe (i mean everything. all i used was the block and head from a 3sfe) got everything back together and car fired right up. ran perfect no problems. drove to the gas station. got some new gas in the tank. drove home (ran perfect all the way back) parked the car for the week because still needed to fix a steering leaking problem. Next weekend, started car went for a little ride around the neighorhood to let things warm up. Half way through the ride, car started acting up. Wouldn't rev past 3k. Would hit 3k and knock back down to 2k. Acts like engine dies and then comes back. Replaced the spark plugs, the coil, the dist cap and rotor. Also replaced the crank angle sensor (it had given me trouble before and so i went ahead and replaced it.) Still the same problem.

It's weird. The car is hard to start now, taking a couple of tries before finally starting, and then if you hit the gas before its warm it dies. Once the car is warm its fine. But once you try to rev, it hits 3k, dies, picks backup at 2k and idles okay. I know it dies at 3k because i can hook up a timing light and watch and at 3k the light quits flashing.

Anyone have any ideas at all? The only thing i can think of at this point is a possible fuel system problem.

thanks

This post has been edited by two55309: Feb 25, 2007 - 10:32 PM

[Silver94CelicaOw...]

Was it ever able to go over 3,000 RPMS prior to sitting or no?

[two55309]

Yea. It used to rev all the way up without a problem. Just that one week is the only thing that changed between it working and it not.

I've also replaced the fuel filter and I just pulled the fuel pump to change its screen. I've changed everything else that I can think of so far.

[lagos]

check your ECU for any stored codes.
it might be your igniter.

[two55309]

i've pulled all the codes from the computer and there was no problem there. I have some software that lets me monitor the ecu, but i can't get a code from it because it happens so fast. (just obdII software reader).

when this happens everything on the dash dies. basically displays what happens when the car has the key on before start.

[Silver94CelicaOw...]

Hmmmm. Thats pretty odd then.

It sounds like something on the 3SFE doesn't quite agree with the 5SFE ECU. It could be a matter of something simply putting out the wrong resistance for the computer to read, I just don't understand why this would happen a week later and not occur right away.


I would examine the problem closer, maybe post up a video of what happens for us to check out.

[Negative]

once you try to rev, it hits 3k, dies, picks backup at 2k and idles okay. I know it dies at 3k because i can hook up a timing light and watch and at 3k the light quits flashing.
The only thing i can think of at this point is a possible fuel system problem.

Doesn't sound like a fuel system problem. If it cuts the spark then why would you think it was fuel related? This sounds like an ECU thing? Kinda like the way the rev limiter works?

[two55309]

Right now I think its fuel related becuase I honestly can't think of anything else.l I've replaced nearly everything in the iginition system, minus the ecu or the ignition computer.

I don't understand either why it didn't show up in the beginning. I've tried reseting the ecu (you know, unplugging the battery overnight) just to see if something was reading wrong, but it starts up with this same problem.

I'll see if I can get a video this weekend of it,

thanks

[two55309]

FIXED.

turns out that i'm a moron. always remember to question yourself. turns out when i was reinstalling the engine i only hand tightened a bolt on the rear of the intake tube that is a ground for the eletrical system (for the injection and fuel system to be more precise). I had hand tightened and before i got a chance to put a wrench on it, i had gotten distracted. it was tight enough at first that it made good contact but through normal vibration it had backed off. every time i would rev, a hose along the firewall would hit it and cause it to break ground. found it by pure accident, just wiggling until the car.

man i feel stupid now