additional Maf input needed

[spongebob]

Need some more input regarding my latest faultcodes, P1126 and P1133. Idle range adaptation bank 1 and 2 according to earlier threads.This is the second time I see them this year.Earlier I have had P1128 and P1130 pointing in the same direction, vaccum leak. However, all these codes do only show up when it is raining for some reason. Checked with Durametric to see the fuel trim and at lower range (2) they are both at 1.30 but at range 1 they are at -1.64 and -1.69 what does this mean, can they differ that much if I have a leak. Also did a smoke test without finding anything.
Durametric did also show an intake temp of 107 F at idle although outside temp where only 59F. Can it be the MAF that is gone instead of a vacum leak or is the intake heating the air that much?
O2 sensors seems to be fine as they are on the same value. Can I do something more before I have to buy a new Maf for test?

Sorry but all spelling errors are due to the kids breakfast in the keyboard..

[Johnny Danger]

Neither the codes that you're referencing, or the symptoms that you're describing suggest that it's the MAF sensor . This link may help .


http://boxster.wikia.com/wiki/CEL_Error_Codes

[spongebob]

Forgot to mention but it is a 2,7 2000 Motronic 7,2.Not sure if it is exactly the same as 5,2. But anyway I see a connection here, if the MAF is faulty it might cause the engine to run either lean or rich and then this is corrected by the o2 sensors.Codes does not always point you in the correct direction.Seems strange as one range seems to be running lean and the other running rich. Not skilled enough though to understand all data that can be collected by the OBD prt

[paulv]

Originally Posted by spongebob

Forgot to mention but it is a 2,7 2000 Motronic 7,2.Not sure if it is exactly the same as 5,2. But anyway I see a connection here, if the MAF is faulty it might cause the engine to run either lean or rich and then this is corrected by the o2 sensors.Codes does not always point you in the correct direction.Seems strange as one range seems to be running lean and the other running rich. Not skilled enough though to understand all data that can be collected by the OBD prt

Sent you a PM. In the meantime, use your Durametric tool and measure the MAF voltage at ignition on and engine off -- should be 0.9 - 1.1 volts; with engine idling, the voltage should be approx 1.4 volts.

I don't know about the earlier MAF sensors but the newer ones also measure intake air temperature.

Regards,
paul...

[Dale_K]

I was getting a CEL with codes that pointed to vacuum leaks (and the oil fill tube was leaking) but the CEL remained even after the leaks were fixed. This was on my 2000 S. I got frustrated and bought the Durametric but couldn't understand the readings and eventually posted my numbers over on the Pelican forum where somebody commented that my readings looked odd and he thought I might have a bad MAF sensor. I bought a new MAF sensor and it instantly cleared up the problems and my Durametric readings went to normal values right away.

I'm not a technical expert and hesitate to give advice but I can say that my car was helped enormously by replacing the MAF sensor. I tried to clean it without success but a new unit worked wonders. And there were never any MAF specific codes being displayed, just fuel adaptation range limits being exceeded. The Durametric wasn't very useful in performing the diagnosis but it did work well to prove the MAF replacement was indeed the fix because the before & after readings showed such a huge improvement for the fuel adaptation values. Those were the FRA and RKAT data points.

Here is a link to the thread on the Pelican forum.

http://forums.pelicanparts.com/boxster-cayman-forum/600891-bought-durametric-but-i-need-help-understanding-numbers.html

[tuanle16]

those codes came up on me too just a few months ago. i checked the vacuum leak by trying to open the oil refill cap with the engine running. if it's difficult to open, then look at replacing your air/oil separator (aos). that did the trick for me.