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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
your 1986 2.8 V6 MPFI does not have a MAP sensor, it has a MAF sensor instead. The MPFI V6 did not get a MAP sensor until 1990, when it went from 2.8 to 3.1 Liters.
Here is your 1986 wiring diagram showing the MAF sensor......
Last edited by OrangeBird; 12-27-2023 at 07:09 PM.
Near the firewall (Pass Side) there is a what looks like some kind of a sensor. I had it off and it has a 4-Prong male connector that attaches to it and on the bottom there is a small rubber tube with a 3/16" hard plastic tube that goes over to the solenoid switch next to the EGR valve. There also are a few more wires attached to it, but I was unable to detach them, so I kind of gave up for now until I can figure out how to get those wires disconnected. Can anybody tell me what that thing is called?
I took a picture of it, but I am having some difficulty retreiving it from my Nikon camera photo file. I'll post iot a soon as I can, so you can see what I am talking about.
The pic would be most helpful, but as it was built by GM in 1986 you car is not supposed to have a MAP, the 1986 diagram clearly shows a MAF. Now, with that said, it was a very common modification in the V6 world to convert the (factory) MAF system to MAP, so sometime in your car's 37 years of life it may well have been converted, involving an ECM, wiring harness, and of course sensor swap.
Figure out a way to post your pic so we can get an idea of what's going on with it......
Hi Vader,
the tan & black are connected to the "Manifold Air Temperature Sensor", and not to a MAP sensor
Good catch! I went back and corrected the post so that no one gets the wrong idea in the future. It gets confusing enough searching old posts for content.
I think the P/D sensor was used on some earlier carbed V-8s as a BARO sensor, and was mounted to the firewall. I'm pretty sure I've seen them stuck to the firewall in some early ThirdGens.
You are correct. I am almost positive it is the Manifold Air Temperature sensor.. The only other MAP sensor is the one connected to the air intake hose that goes to the throttle body and the air filters.
Recently, I had a 32 code, so today I took off the EGR valve and cleaned it good, but it really was not that loaded with carbon. I had replaced it about a year ago. At times I get a 34 code, which pertains to the Mass Air Flow Sensor. I've replaced it once or twice, and I also make sure the screen is good and clean. There isn't much on that engine that I have not replaced, since buying it 5 years ago off the original owner. It has about 150,000 miles on the engine and it really runs like a dream. I love driving it. Recently, I bought a used radio/CD player. Now when I am out driving I 'm listening to my rock and roll music from the 50"s and 60"s.Even though it it not a real show car, but I still get a lot of comments from people how good it looks. I love going to car cruises and car shows. I am a car guy I love working on my car. I am always replacing something, just to keep busy. I just turned 79. Oh, by the way, I buy almost all my car parts from Rockauto.
12-27-2023, 10:33 AM
