MAP sensor existence?
This is a '91 2.3L EFI Ranger S 2WD made in 06/91.
I haven't been able to find mine. The access port into the plenum where everyone says it should be is empty, so is the access port in the middle (which I figured anyway, but why not try...)
Some guys say the sensor is on top of the heater core and you either have to remove the dash, or remove the entire heating apparatus to get to it.
I've also read that if your truck says "Solely for sale in the state of California." it will have a MAF and not a MAP.
Still others say you can have both.
I need some clearing up before I rip the passenger-side of my truck open possibly for no apparent reason (plastic pieces never go back together right and you always end up with a rattle).
I've been hunting and pecking at this because it smokes like a Banshee, idles rough, and misses. All common problems to a faulty MAP sensor. I just can't find it. I'm starting to think I only have a MAF.
I cleaned my MAF with Brakleen at the recommendation of a mechanic and the smoke noticeably decreased and the idle turned to a barely noticeable quiver, which I've heard is common for 4-bangers, though mine never did it before. I could be hyper sensitive because I've been sitting in it trying to time the miss and feeling for every little bump.
I just replaced the head with a brand new one, lapped valves, new guides, new seats, entirely new seals along the intake route.
I checked the breather tube for leaks, as well as every line I could see with a soapy water solution and a paint brush (how I was taught to do it) and everything was fine and dandy. So I got out the trust vacuum gauge and went to town and everything was also fine.
The valve cover has insane vacuum and actually sucks oil up into the throttle body, and the PCV line also has a ton of vacuum, but that's normal.
I cleaned my oil separator thinking it was causing backpressure, but it's entirely the opposite.
I'll clean my IAC later, having that stuck open can be a really bad problem, too. When I unplug it at idle, nothing changes...
I got a code for my ECT and my O2 sensor, replaced those, still getting a code for my ECT. I've got about 12 ohms of resistance on the ECT harness and about 30 on the ECT.
'91 Ranger, 2.3L 4-Banger knocking out 140 HP. Plopped the head out of '94 and an RV cam in it. 2WD, zero options. But, I love her to death.
Avatar is when I drove up the Bohemia mining saddle in Oregon, a fairly well-known 4WD trail around here.
Last edited by Rangerlove; 07-09-2011 at 03:19 PM.