CEL codes P1128 & P1130

[speedyspaghetti]

Originally Posted by dsallean

I cleaned the trottle body and the MAF, then replaced the MAF, checked and replaced the throttle body gasket and oil filler cap and every time I reset the codes would come back. Kinda running out of ideas and then I noticed a crack on the underside of my dipstick tube. The tube was brittle and when I took off the upper part that goes thru the bulkhead it just broke in two pieces. I replaced the tube (very easy and not expensive). Since then no CEL codes.

Interesting idea - I'll have to check that. I'm hoping it is something that simple. I'm probably going to sell the car soon and I want it all working properly.

[Steelepuls]

Speedy, I too am having the same codes and it started just two maybe three weeks ago. I've done the same things you have, cleaned the MAF, checked for vacuum leaks, checked the oil cap, replaced all the coils, and cleaned the throttle body. Once I clear the codes, about 50 miles later they come back. I am currently late on the smog test due to the CEL and monitors not clearing.

I'm wondering if the low humidity we have been having in the last month could be the problem. All summer long I've had no CEL, but two weeks ago they popped up when the cooler dry air came in.

Anyone else have this issue?

[kk2002s]

When I got these codes it was because of a poorly seated AOS to TB hose. I had removed to clean the TB and Pipes and I didn't seat it back properly. I think you have a vacuum leak unless you have a defective MAF. But people do have issues with the Oil fill and dipstick tubes. Any where a vacuum is present for both banks.

As far a AOS vacuum, the quickest test you can do is remove the Oil fill cap while the engine is running to see how much vacuum you feel there. Should have some but not overpowering.

[blue62]

Originally Posted by Steelepuls

Speedy, I too am having the same codes and it started just two maybe three weeks ago. I've done the same things you have, cleaned the MAF, checked for vacuum leaks, checked the oil cap, replaced all the coils, and cleaned the throttle body. Once I clear the codes, about 50 miles later they come back. I am currently late on the smog test due to the CEL and monitors not clearing.

I'm wondering if the low humidity we have been having in the last month could be the problem. All summer long I've had no CEL, but two weeks ago they popped up when the cooler dry air came in.

Anyone else have this issue?

"If" your MAF sensor is the problem cleaning it doesn't always correct the problem.
Perhaps it needs replaced????

As to your question about low humidity.
the MAF sensor accounts for changes in humidity when it is functioning properly.

[Steelepuls]

Originally Posted by blue62

"If" your MAF sensor is the problem cleaning it doesn't always correct the problem.
Perhaps it needs replaced????

As to your question about low humidity.
the MAF sensor accounts for changes in humidity when it is functioning properly.

Blue,
The MAF is only 2 years old, along with new O2 sensors. What I tried today was cleanning the throttle body and recalibrating it. It seemed to fix the CEL coming on after about 20 miles of driving. I now only have the SAI monitor after driving about 40 miles. Hopefully I can continue driving it so I can reset the last monitor with no CEL. Then I can get the smog finally and hopefully it passes.

[Jager]

With those two trouble codes, P1128 and P1130, the AOS is also suspect.

[blue62]

Originally Posted by Jager

With those two trouble codes, P1128 and P1130, the AOS is also suspect.

There is a spec for vacuum at the oil filler cap. It Has to be read with a manometer as a regular vacuum gauge is not calibrated fine enough. I do not know the spec but if it exceeds the spec then the AOS is suspect. This info has been posted by member "JFP in PA" so if one does a search you should be able to find the info.

[blue62]

I just went and did a search under manometer.
The spec calls for under 5in/wc at operating temp.
You need a manometer and an oil cap with a fitting for the vacuum hose.

[Fred111]

Originally Posted by Steelepuls

Blue,
The MAF is only 2 years old, along with new O2 sensors. What I tried today was cleanning the throttle body and recalibrating it. It seemed to fix the CEL coming on after about 20 miles of driving. I now only have the SAI monitor after driving about 40 miles. Hopefully I can continue driving it so I can reset the last monitor with no CEL. Then I can get the smog finally and hopefully it passes.

I have had these codes for a while. I cleaned the MAF and helped briefly. I finally bought a used one on ebay a few days ago and so far the codes are gone.