Offroad-Express

new install 1uzfe into 82 hilux.......


but there is a problem

ill try to describe the problem as best i can so bear with me

1) start up hot and cold fine (((awsome))

2) give it a boot full and it revs hard (excellent)

3) increase rev from idle to say 1500-2000(dont have rev counter yet)
gets to 1500-200 and revs drop back to almost stall hold the throttle at same position and then it picks up again to same 1500-2000 the falls.. take foot of throttle and it resumes a good idle ((( this is the problem)))

Dodgy AFM???

Could be TPS.

I have seen similar happen on 1uz with disconnected afm.

unplug yours and see what happens,

tried disconnecting afm and it just stalls dead stop

ECU?
Had a mazda 1500 turbo once. I kept driving on the turbo timer by mistake
When the power was cut, I got lazy and would keep my foot the same and not clutch it, turn ignition back on but this caused a "burnt spot" in the ecu programming and caused the same symptoms.

had a tweek with the tps it did increase the rpm at idle but that was it ...my god son (19yrs) asked if the same problem existed when driving ?? i said dont know.so off we go for a blast down the road and the problem vanished!! returned home to find a smooth idle a quick and steady response to the throttle no dead spot nothing.. the only thing that changed is the temp...so im wondering was the choke still engaged i don,t know..any ideas....

Doesn't sound like an air-flow meter problem to me. I'm guessing it could well be the idle speed control valve. Take it out and give it a good clean out and see if that fixes anything.

Cob Webs
Must of been in need of an "Italian Tune up"

you don't have everything hooked up right and the ecu is throwing limp mode.. check your wiring..
from memory it'll be that the auto trans is not hooked up and I can't remember but placing a fuse in the loom on one of the plugs will eliminate that as the ecu doesn't see the trans(placing the fuse in the ecu will see a connection) BUT i could be wrong.. someone else may chime in..
Check http://www.lextreme.com for more info.
whats ya ecu pin config? mine was a 40/40/40 pin and they are easy to wire up. cheers

Oh i'll be rewiring mine in the next week or two having pulled it from my old 70.. I could maybe help if it's a 40 pin job..

flyingbrick wrote:I have seen similar happen on 1uz with disconnected afm.

unplug yours and see what happens,

With what he said if you do that it'll revert to a base map so you can get home.. it'll run quite happyly but the fuel economy will go throw the roof.. cheers

find a pinout diagram of the ecu.

could be several things

engine speed sensor, afm, vacuum leak or if it was originally bolted to an auto and is running the ecu from the same car you will need to trick the ecu into thinking the gearbox behind it is in either park or neutral.

Could also be fuel reg. If the pressure does not build up enough in the fuel rail it will idle sweet, but as soon as you suck the fuel out it starves as the regulator is not holding the required pressure.