JeTTe35

Was having rough idiling issues, so i took to mechanic. He said I need to replace the MAP sensor. Looked in manual and they say where MAP sensor is and how to replace. They say its on left rear corner of intake manifold, even showing small close up pic, making it look like it is easily accessible. But I cant find it.

Anyone shed light on this?

rodj

Find a new mechanic.
85 -89 TPI are MAF

It is if you have a 90-91 TPI which use MAP

JeTTe35

So your saying the Code 33 that he seen is the MAF sensor on my 85?

Bondami

X2 Find a new mechanic, the Mass air flow sensor is right out front over the radiator in the intake air tube.

JeTTe35

Not arguing on the mechanic, but you get what you can pay for.. And as times are I payed for him to hook up equipment out of his house. Was told to buy and replace MAP sensor.

Bondami

nope.. the car doesnt have a manifold absolute presure sensor.. its a Mass air flow sensor. do your self a favor and go buy a can of sensor safe throttle body spray cleaner (like carb cleaner but for Fuelie cars)

Spray that inside the MAF (there will be a screen and two small wires, just spray them off) the MAF pops right out of the intake tube. If the car runs ok other than rough idle I would bet its dirty.. and a sa new MAF can go 300 bucks..

65Z01

cumbercr

To confirm the MAF is the problem, disconnect the wire harness from the MAF. If the idle improves, the problem is the MAF. If not, look elsewhere. Like someone else stated, spray the inside of the MAF with MAF cleaner. You can get it at any auto part store.

azrocketman

Have you ever replaced the MAF relays? MAF relays can generate codes 33, 34, and 36. If the '85 is like an '86 they are located on a bracket behind the battery on the driver's side. One relay provides MAF power and the other controls the MAF burn-off (After the engine shuts down the burn-off circuit provides power to the MAF sensing wire to burn off contaminants). Cost is about $20.00 for new relays. Most folks consider relay replacement preventitive maintenance on these cars.

Steve

AGENT 86

Unfortuantely, 85 uses a one year bastard MAf module that is hard to come by.
Glad I bought an 86

Pete K

Did he mean Mat sensor?
Manifold
Air
Temp

azrocketman

Is it still a weak link like the '86 relays?

Steve

rons85

Nope, it's about as dependable as the Frame. The redesign to the paired relay arrangement was to save cost, apparently - it did NOT help the reliability. The '85 MAF modules do not fail.

They aren't that hard to Find, either - NAPA...

RonsRed88

I think Pete is correct, the MAT sensor is located where you described. It's on the bottom of the plenum and hard to see until you remove the plenum.

Ron

AGENT 86

Yes, if you want to spend $324 on a new aftermarket unit. I was referring to a used 85 GM unit.