I just bought a '90 Ranger with the 2.3. It has a "cold air intake" that the previous owner installed, although it's just sucking in hot air from under the hood. I noticed the mass airflow sensor isn't hooked up. I can't find the harness that plugs into it and I don't see where it would have been cut off. The truck runs perfect, though. How is that? If anyone could shed some light on this for me, I'd appreciate it!! Any info on a wiring diagram online that would help me would be great also.

Thanks

Trevor

 

Holy crap! No MAF and it still runs? Something is fishy...

Does it get moderate gas mileage?

 

Weird, huh? I know it's not the original engine, Would later model engines not have a maf sensor? I don't know what year the engine is, though. It seems to get pretty good milage, but haven't checked it.

 

I was told today that the 4 cylinder trucks didn't have a maf sensor until '93. Any truth to that?

Thanks

 

I don't have any 1990 documentation but I do have a wiring manual for 1989. That year's 4-cylinder Ranger was "speed/density", meaning that the airflow is not actually measured. Instead, the airflow rate is inferred from manifold pressure and RPM. This is a good system as long as the engine remains basically as the factory built it.

My 92 and 93 books show the 4-cylinder Rangers as having a "mass air" system that uses a MAF sensor to measure the actual airflow. This system is more precise than speed density and can compensate for production variability and aging. In general, mass air can also tolerate some engine mods better than a speed/density system can.

From your description, it sounds like your engine is speed/density.

 

FWIW, according to the venerable Charles O. Probst, the '90 2.3L (VIN code A) uses a Speed Density system to calculate engine load, the exception being CA vehicles, in which case MAF systems are used. So I believe you are correct Bob.

 

Thanks guys! I appreciate the info.

Thanks again

 

Yeah good job guys! But we all forgot something...

Why does his speed-density motor have a MAF sensor?

 

Agreed.

 

you guys are right. I found out from the guy I bought it from the the maf is from a v-6 truck that the cai came off of.

Thanks again!!