I need a little help tracking what exactly my problem is. The vehicle is a 1996 4Runner, 3.4, 5spd, 4x4. The 4runner was wrecked (right front damage) but still ran great, and while fixing it I decided to swap in the lower mile'd 5VZ-FE from my '99 donor 4Runner. I kept all elec off the 96 engine except the newer style MAF and air-box.

now it isn't running so great.

OBD-II codes:
100 (MAF circuit)
101 (MAF actual input different from actual)
110 (IAT sensor circuit)
1300 (Igniter circuit)

SYMPTOMS ARE:

Starts and dies

will start and high idle on second or third try

warms up and idles down to 750rpm (slightly rough sometimes)

throttling slowly it revs smoothe

hitting the throttle bogs down (and it stays bogged until I let off)

exhaust is strong smelling and leaves carbon mark on driveway under tailpipe

I can drive it if I'm easy on the throttle, but if I get into ANY hurry at all it's gut-less


WHAT I'VE DONE, OR KNOW SO FAR:

cleaned MAF w/ elec cleaner

cleaned throttle pos sensor (tried the spare)

cleaned throttle body (tried the spare)

checked for vacuum leaks

checked for any loose wires or bad grounds

Compression check (180+ on all 6cyl)

new NGK plugs


I'm wanting to say this is a wiring issue. Any ideas? Is there a possability of an issue in the fuse block? Maybe resetting the ECU? (I did try to clear the codes on the OBD-II)

thanks for any input

 

Your pins on the maf are different now since you are still using the 96 harness and ecu. Get an EWD and switch the pins around to the right spots

 

x2 what he said.... it will run great then

 

X3

Definately MAF pinout problem.

 

that.... would be awesome.

I did try swapping back to the 96 intake tube and MAF to see how it would run. It ran better, but still not great (but none of the codes were reset at).

I'd still be using the old style MAF- but the 96 air box was crushed in the wreckage

thanks- I'll post outcome (might be this weekend)

 

Yeah that was it. 4 of the 5 wires were in the wrong spot- amazing it ran at all.

Thanks for the info

 

It would run the same as if the MAF was unplugged.
......which is pretty bad, but it will run nonetheless.