BHUDDA

First off, truck is 1992 Toyota Pickup 2WD stripped down 85,000 Miles on the clock and yes is 85 not 185 lol. Well the problem all started when The truck had some rough idle and that got me curious. Such a simple motor I got to poking around and discovered that if i unplug the throttle positioning sensor the truck runs decent just the idle is a little high and the truck has reduced acceleration. I replaced that and that still didn't fix the problem but I left it in anyway. So next was the mass air flow sensor, expensive part, so i replaced that. Truck ran great with no problems. then about 4 months later same problem. Again unplugging the TPS solved the rough idle. So under warranty I replaced the MAF and again running like a top. So last week it started again. I am just baffled to what could eat up those MAF's I could just keep replacing them but I really want to get to the bottom of this, Any Ideas? ANY help would be greatly appreciated to get my baby back on its feet!

EDIT
Doing a little reading about the TPS and i'm reading something about adjusting it? Should I have done that when I installed it, could that be eating up MAF's?

Co_94_PU

iTrader: (-1)

Well firstly it's a VAFM(Vane Air flow meter, or AFM) not a MAF(Mass air flow), so if you cleaned it like it was a MAF you broke it It's not supposed to be exposed to chemicals.

You'll need to do the inspections, both the resistance tests at the AFM and the voltage and resistance checks at the computer. Could be anything from flaky/wet wires to dirty/wet/loose connectors.

There are usually water proofing of some type on the under hood connectors, rubber O-rings and/or rubber bushing/plates. These are good but they're not fool proof and are prone to failure, best to use a dielectric water proofing grease.

BHUDDA

No, didn't clean it. Sorry for the confusion, Name of the part I bought was mass air flow sensor lol. But I'll try to get under it tomorrow and check out all the wires.

wyoming9

iTrader: (1)

If it ran good for a few months.

Was there any thing you noticed when it started running bad again

Like very heavy rains driving through a creek .

Perhaps doing other work around the engine .

Is the spring clip that holds the plug on still there.



Maybe I just have good luck I never had a AFM fail yet

Be nice to know where you live help could be close at hand

BHUDDA

The only thing I noticed was the rough idle. There is nothing else mechanically wrong with the truck. I live in ohio, the truck never sees snow, it hardly ever sees rain its a garage kept truck. The plug is secured.

Gamefreakgc

The issue is probably not due to you VAFM. Having two go bad is unheard of.

Yes, you do need to adjust your TPS. This is most likely the culprit, it was for me. Read up in the Factory Service Manual on how to do it, you'll need a multimeter ($10), a feeler gauge ($4), steady hands and LOTS of patience. It's an easier job with two people since one can hold the multimeter in place while the other slowly turns the TPS to spec. Easier done with the Throttle body off but then you have to change the gasket.

BHUDDA

Thanks! yeah it just started acting up today I just ordered a manual and Ill be doing adjusting that as soon as it gets in.

Gamefreakgc

While you are at it, also check the ECT sensor (Engine Coolant Temperature Sensor). It's a cheap part that often goes bad after time and could be sending bad signals to the ECU and the TPS. For the 22RE, I believe it's on the backside of the engine on the coolant bypass. It should be a green or gray sensor. It's smaller than your cold start injector switch (right next to it) but has the same connector.

T4R War Eagle

Having same prob with mine too keep me informed,thanks.

GasTurbine

I don't know if they moved it, but on my 85 and 86 4Runners with 22REs the coolant temp sensor is in the front on the engine. Very easy to get to, and right beside the larger cold start time switch.

T4R War Eagle

Changed ut out allready,today its runin fine