Another P1128 and p1130

[DaveRad]

Hello there everyone, I’ve been chasing this problem down endlessly and nothing seems to work, I’m truly at my wits end. I got these 2 codes, and here are the symptoms

Hunting idle

There seems to be a decrease in power, it feels like there’s more power on the table. Some days I start up the car and it feels fast, other days it feels slow.

Here’s what I have done to no avail to remedy the car

Replaced the AOS

Poured some Techron in

Cleaned the MAF

I’ve had the car smoked at a shop, and they didn’t find a vacuum leak.

My idle MAF reads about 10kg/hr with AC off, and here are the fuel trims

short term bank 1 and 2 bounce around from -.8 to 0 to 0.8

Long Term Bank 1 32%

Long Term Bank 2 30.5%

Can anyone make sense of this? Help would be greatly appreciated.

[DaveRad]

Update: a new code has appeared today, P0102, it’s a pending code, but still concerning. Im leaning towards buying a new MAF, is this the right choice?

[blue62]

What year is the car?
How many miles?
Any mods to the intake or exhaust?
Are you running a stock air filter or after market type?
Any oily residue any place on the engine?

[DaveRad]

Originally Posted by blue62

What year is the car?
How many miles?
Any mods to the intake or exhaust?
Are you running a stock air filter or after market type?
Any oily residue any place on the engine?

1998
55k miles
No
Stock
No, when I replaced the AOS I also cleaned out the throttle body. There is as some oil residue in there

[blue62]

If you ran the car with the MAF unplugged or had the Key on with the MAF unplugged you will get the P0102 code.
If you didn't do that then the MAF is suspect...a bad MAF can also cause your other codes.
so I would replace the MAF clear the codes and see what happens.
If you replace the MAF replace it with a Bosch these cars don't like after market sensors for some reason.
Keep us posted on results please...

[DaveRad]

Originally Posted by blue62

If you ran the car with the MAF unplugged or had the Key on with the MAF unplugged you will get the P0102 code.
If you didn't do that then the MAF is suspect...a bad MAF can also cause your other codes.
so I would replace the MAF clear the codes and see what happens.
If you replace the MAF replace it with a Bosch these cars don't like after market sensors for some reason.
Keep us posted on results please...

Sounds good, will do. Thank you very much. I’ve read that the MAF’s are very specific for the year, do you know which one I can buy?

[JFP in PA]

Originally Posted by DaveRad

Update: a new code has appeared today, P0102, it’s a pending code, but still concerning. Im leaning towards buying a new MAF, is this the right choice?

P0102 is either a wiring issue or a harness short to ground. You need to be testing the wiring running from the MAF to the DME. The MAF itself may not be involved.

[DaveRad]

Originally Posted by blue62

If you ran the car with the MAF unplugged or had the Key on with the MAF unplugged you will get the P0102 code.
If you didn't do that then the MAF is suspect...a bad MAF can also cause your other codes.
so I would replace the MAF clear the codes and see what happens.
If you replace the MAF replace it with a Bosch these cars don't like after market sensors for some reason.
Keep us posted on results please...

I’m trying to find the right MAF for my car, which one is the one I need for a 98?

[blue62]

You can check the MAF voltage with your Durametric
Should show 0.9 volts - 1.1 volts ...with key on engine off
1.2 volts - 1.5 volts engine running at an idle

[DaveRad]

Originally Posted by blue62

You can check the MAF voltage with your Durametric
Should show 0.9 volts - 1.1 volts ...with key on engine off
1.2 volts - 1.5 volts engine running at an idle

Unfortunately I don’t have a durametric, I got my readings from a $30 OBD2 reader

[blue62]

Originally Posted by DaveRad

Unfortunately I don’t have a durametric, I got my readings from a $30 OBD2 reader

Does it show MAF voltage?
In your first post you stated that you got reading of 10kg/ph for a MAF reading.
So I assumed you were getting a MAF signal.
BUT JFP in PA is correct that you need to prove your MAF wiring is sound.
MAF voltage would be another way to check for a signal
or see if the MAF reading on your scanner changes with engine RPM.
I am just looking for an easy way to confirm that the ECU is getting a signal from the MAF.
If the ECU is getting a signal then the wiring is good.

[JFP in PA]

Originally Posted by DaveRad

Unfortunately I don’t have a durametric, I got my readings from a $30 OBD2 reader

Do you have a multimeter? If so, check the continuity of the wiring from the MAF to the DME; this is exactly what the OBD II manual for your car says to do if you get P0102; and just a by-the-by, if the wiring is sound, the next step is to check the DME..........

[DaveRad]

Originally Posted by blue62

Does it show MAF voltage?
In your first post you stated that you got reading of 10kg/ph for a MAF reading.
So I assumed you were getting a MAF signal.
BUT JFP in PA is correct that you need to prove your MAF wiring is sound.
MAF voltage would be another way to check for a signal
or see if the MAF reading on your scanner changes with engine RPM.
I am just looking for an easy way to confirm that the ECU is getting a signal from the MAF.
If the ECU is getting a signal then the wiring is good.

Unfortunately no, there’s no option to read MAF voltage. Could this possible be done with a multimeter?

[DaveRad]

Originally Posted by JFP in PA

Do you have a multimeter? If so, check the continuity of the wiring from the MAF to the DME; this is exactly what the OBD II manual for your car says to do if you get P0102

I do. Where would I find that connection?

[JFP in PA]

Originally Posted by DaveRad

I do. Where would I find that connection?

OK, disconnect the harness at the MAF and at the DME. Pin #4 at the MAF end is the same as pin #47 at the DME, test it for continuity; pin #5 at the MAF end is the same as pin #17 at the DME end, test it for continuity. Then test both wires for a short to ground. If everything passes, it isn't the harness, if any wires fail, you need to find the break or ground and repair it.