Ok so my friend has a 1986 4Runner that i'm looking at buying, i know the truck very well. Its a 22re automatic, but its a pig on gas for some reason. It'll take $20 worth of fuel to do the same trip his 91 ext.cab 4cyl 5-speed will take $10 to do.

Now when he first got it someone bypassed the fuel filter, which eventually ed over all the injectors. Now we spliced in ones from his old runner, which was a 90 or 91 but they had 2 holes in them instead of the 1. Are these different rate injectors or do they just atomize the fuel better? Could this be why its harder on fuel.

Thanks in advance.

 

I didn't think the older injectors would even work with a newer harness, and vice-versa.

Rob

 

They don't...as exact plugs ins. But if you notice, he said he spliced them in

If the injectors are bigger, they are likely adding more fuel when they are open (Bigger injector means more fuel able to pass through in one pulse) but the truck has not been compensated as such. I would suspect that is the culprit.

You also have differences in weight however. IIRC, the 4Runner weighs more than the truck, and is not as Aerodynamic, so that will affect overall MPG's too. Tack on Automatic vs. Manual, and a well worn drivetrain, and viola you have your differences.

 

ah i see... thanks for the replies so far.

I can see where the weight and drivetrain losses come into play... Just didn't think it would affect it that much.. Its definetly running rich due to a presence of some black smoke ( unburnt fuel ).

My main question is there a difference from the newer injectors that are in the truck, to the older ones that were in it besides the obvious wiring differences and appearance with the 2 holes in the newer, vs the 1 hole in the older. If they have different flow rates or # or whatever it is.

Thanks.

 

I'm not sure if Toyota uses low or high impedance injectors or both, but that could also be a factor. Usually OBD-0 would use the low impedance and OBD-1 would use the high impedance injectors. That's how it was for my old Honda's anyways. You could usually tell by the difference in the connectors. You could use the low impedance injectors in the high impedance vehicles, but you needed to use resistors. Saturated/peak and hold

 

Ok so i did some research.

According to repair manuals, the trucks supposed to have early obd-0 injectors, with a resistance of 1.0-2 ohms roughly. The ones that are in it are 13.4-14.2 ohms.

How does this affect it?? Could it make it run rich?

 

that is correct, but i'm doing it bass-akwards using high impedance in a low impedance situation. its 1991 injectors in a 1986.

 

lol I'm not sure what to tell you than. That was never a common swap AFAIK. I'm not sure if that could ever be fixed, reasonably anyways.

 

Well i'll be switching out for the proper injectors this weekend... I'll let you guys know how much of a difference it makes, and also let you know don't let stupid people do stupid things haha.