running lean

[Eddie the Eagle]

took my plugs out as i was missfing, had turbo plugs in my NA with the wrong gap. also cause its been running lean it has burt the tips away. how to i adjust the mixture for more fuel??? have put new plugs in

[Nick@TC]

You can't!!!!!!!!!!!

It's all done by the ECU, could well be the O2 sensor bolloxed.

[Eddie the Eagle]

were is this. i bet its costly. is there an O2 sensor on an 88 NA auto the same as one on a 90 NA manual

[Bryank]

You *might* not have an o2 sensor though.. my '89 doesn't have one, but somewhere then they started having them. If you look at the exhaust manifold, by the dipstick, you'll see the o2 sensor bolted into it where there is a gap in the rear heatshield, or a blanking plate with two bolts..

My '92 motor had an o2 sensor, which got junked as my '89 ECU doesn't have an o2 input..

I would think an 88 doesn't have one, but then there does seem to be quite a few variations out there so it's possible lol

If she's running lean and there is no o2 sensor, then check for air leaks, as this is the likely reason, or the AFM is possibly dodgy/jamming..

[darket69]

Mixture adjustment is possiable on a pre catted NA .. there is a screw on the afm .. this will give you a very basic and small adjustment to the mixture but this is very unlikely to be the cause .. try cleaning the afm with brake cleaner and checking the timing .. i would say that unless you have a vac or inlet leak somewhere then the timing is the most likely cause .. that is however if the plugs were not just erroded away due to a sevear amount of miles on them !

[Nodalmighty]

You *might* not have an o2 sensor though.. my '89 doesn't have one, but somewhere then they started having them. If you look at the exhaust manifold, by the dipstick, you'll see the o2 sensor bolted into it where there is a gap in the rear heatshield, or a blanking plate with two bolts..

My '92 motor had an o2 sensor, which got junked as my '89 ECU doesn't have an o2 input..

I would think an 88 doesn't have one, but then there does seem to be quite a few variations out there so it's possible lol

If she's running lean and there is no o2 sensor, then check for air leaks, as this is the likely reason, or the AFM is possibly dodgy/jamming..

You can richen the fueling by fitting a resistor in series in the coolant temp sensor wire at the ECU. This is how that AHEM! "20bhp mod" on ebay works.

As it's an NA the flap mafs can usually have the internal spring tension altered to recalibrate it's voltage curve (but knowing toyota, this one can't be :rant: ) .

Nod.

[peter]

took my plugs out as i was missfing, had turbo plugs in my NA with the wrong gap. also cause its been running lean it has burt the tips away. how to i adjust the mixture for more fuel??? have put new plugs in
If it was running O/K before this problem arose then its probably an air leak, as the mixture and timing don't as a rule just go out of spec'. Unless of course someone has been messing with it not knowing what they are doing. So, my answer is, find the cause before messing with mixture screw, particularly if you do't have a CO Meter. :duck: