Hey guys new here. I have looked everywhere for the MAP sensor. Does anyone have a pic or diagram of where it is on a non supercharged 1995 Bonneville. I found the PCV valve under a cap with a bolt on it. but for the life of me cant find the MAP.

The reason im looking for it, is because the engine idles rough an sometime stalls out. I have changed the MAF and the sensor on the air intake.

Another problem is the ECT sensor reads normal then jumps to 300 and stays there for a bit then back to normal. I have changed the ECT (under the thermostat, 3 prong connector) and still does it.

Thanks for any help you can provide, i have hit a wall.

I think this might help you out. I hope so
Remove the grey upper engine cover, standing in front of the car, you will look over the top of the engine and see fuel rails that go across the top of the engine. The sensor is located at the back of the engine just next to the fuel rails. Its a black, rectangular device that is about an inch and quarter by three inches. There is a 4 wire connector and a vacuum line going to this unit. Be careful removing the vacuum line and connector, they become brittle. If you replace the sensor, also replace the vacuum line going to it with the proper size and distance.

95'* don't have a MAP sensor.

Check all of your vacuum lines and test your Throttle Position Sensor.

Along with Mike'* suggestion might I add my '94 had rough idle that would smooth out once i stepped on the gas....turned out to be the EGR valve. Replaced that and smooth idle returned

Just wanted to say that i have fixed the problem and have passed emission tests. The problem was a bad PCM. PCM kept giving codes even though the sensor was sending them. Finally fixed thanks to this site.

It'* odd that your PCM would do that, but I'm glad you got it fixed!

LOL, the 95 PCM'* have been know to be flaky. I'm glad I didn't have a bad one when I did own it.

Based on it still operating except wrong values triggering codes, I suspect it might have just had dirty or oxidized contacts on the PCM itself or the harness connectors, introducing addt'l resistance and/or intermittent contact that changes the sensor voltage (signal).

i saw ur quest casue i was actually searching for diff issues, but figured stop by real quick. so not sure if anyone mentioned this but i ur car dont have MAP it should have MAF or some else atleast. Map is what reads barometric pressure from vac lines running from intake, u will find MAF somewhere on throtle hose going from it to the air filter.