MAF Sesnor Problem

[bve32k]

I am getting a MAF sensor error now on my car since I re-did the timing. I went to the u-pull it the other day and grabbed another MAF from a 95 Monte Carlo and installed it today. I am still getting the same error. The error I am getting is P0101. I don't even know where to start now.

The only other things I did was changed the air filter, plugs and wires and I added in the chip that Ben made me to delete the EGR, I also put in a better condition computer from the Monte Carlo and swapped out the chips that were in my car.

[Darin]

Here is a quick run down on a few things to check.....

Inspect for the following conditions:
An incorrectly routed harness--Inspect the harness of the MAF sensor in order to verify that it is not routed too close to the following components:
- The secondary ignition wires or coils
- Any solenoids
- Any relays
- Any motors
A low minimum air rate through the sensor bore may cause this DTC to set at idle or during deceleration. Inspect for any vacuum leaks downstream of the MAF sensor.
A wide open throttle (WOT) acceleration from a stop should cause the MAF sensor g/s display on the scan tool to increase rapidly. This increase should be from 6-12 g/s at idle to 230 g/s or more at the time of the 1-2 shift. If the increase is not observed, inspect for a restriction in the induction system or the exhaust system.
The barometric pressure (BARO) that is used in order to calculate the predicted MAF value is initially based on the MAP sensor at key ON.
When the engine is running the MAP sensor value is continually updated near WOT. A skewed MAP sensor will cause the calculated MAF value to be inaccurate. The value shown for the MAP sensor display varies with the altitude. With the ignition ON and the engine OFF, 103 kPa is the approximate value near sea level. This value will decrease by approximately 3 kPa for every 305 meters (1,000 feet) of altitude.
A high resistance on the ground circuit of the MAP sensor can cause this DTC to set.
Any loss of vacuum to the MAP sensor can cause this DTC to set.

[bve32k]

Check all the wiring. Changed thr MAF to a used one I got from the u-pull it. Electrical is out of my league so I think I am giving it up.

[Juglenaut]

Fuel advance problem possible check rated fuel pressure.

O2 undercompansated A/F check O2.

Leaks after MAF.

Possible wiring fault, could be the connector.

[Juglenaut]

I also put in a better condition computer from the Monte Carlo and swapped out the chips that were in my car.

Hmmm Seem like this is the pointer...

I need you to verify current application to the T:
Year
Make
Model
Transmission
Engine

Donor ECM:
Year
Transmission
Engine

CAL pacs or EEproms are highly prone to static damage.

Lastly why did you replace an ECM that may have been working or at least you never said the old one failed.

[bve32k]

Hmmm Seem like this is the pointer...

I need you to verify current application to the T:
Year
Make
Model
Transmission
Engine

Donor ECM:
Year
Transmission
Engine

CAL pacs or EEproms are highly prone to static damage.

Lastly why did you replace an ECM that may have been working or at least you never said the old one failed.

My car:

1995 Grand Prix GTP
Tranny: 4T60-E
Engine: 3.4L DOHC

Donor car I belive was from a 96 GTP, same tranny and same engine.

I replaced the ECM because the one in the car that I had I opened up put Ben's chip in and it was like filled with dirt or sand or something. When i opened it up 3 out of 4 screws broke. Then I couldn't get the mother board out of the case to clean it up. I thought I messed it up so I went to the U-Pull it and grabbed one from a 95 Monte Carlo and just swapped chips. There was no dirt in this one and no rust. Mine had so much rust on it.

I did some more testing with Ben's chip. I capped off the EGR so I didn't bother putting it back on. I got the car all together and then SES light was coming up. Plugged the scan tool in. MAF and VSS sensor were coming up bad. I then put the stock chip back in. Only error that came up bad was a circuit fault. Plugged the EGR in and it went away. So I plugged Ben's chip back in still coming up with MAF and VSS sensor codes. Then I plugged the EGR in while the car was running and it went away. So I come to the conclusion it needed to finish the circuit for some reason. But the EGR code wasn't coming up at all when ben's chip went in the car because he deleted it.

[Juglenaut]

You may have swapped in a mid generation ECM.

1995 ECM:
1. Uses Digital EGR
2. Uses stanalone MAF, Pin D15
3. Uses the KPS to drive the injectors, and ICM has a low res KPS input.
4. May not have a map
5. VSS pin Location 17 Red 22 Pin Connector Position B21, B20 (may very)

1996 ECM:
1. Uses a Linear EGR
2. Uses a EGR circuit intergrated MAF, Location 1 80 pin connector Position 68, 54.
3. Uses 2 KPS sensors one low and one high resolution, computer drives ICM and injectors.
4. Has both MAF and MAP.
5. VSS input pin Location 1 Blue 80 Pin Connector Position 47, 6.

Something doesn't sound right, you may have gotten a hybrid mid generation that was flashed to use all the stuff on a 1996 engine. I Would get a ECM from the same year just to play it safe.

[bve32k]

I have the 95 ECM. It's not the silver boxes that the 96's have. It is a black box. The car is running now. It was running before I plugged in the EGR too so I am guessing it was fine because if the MAF sesnor was bad the car wouldn't start. But now the EGR is plugged in with no codes, it is still blocked off though. Just doing nothing.