Help with cel and p codes

[boxsterg]

CEL light is on again. Just got Durametric. It says P1128 Porsche FC 360 oxygen sensing adaptation idle range bank 1, P1130 PFC 361 Oxygen sensing adaptation idle range bank 2, P0159 PFC 23, sensor ageing behind converter bank (4-6)
Just got the durametric. Is there further diagnosis I can do to track this down? or what exactly does oxy sensing adaptation mean and what should I be looking for. I have recently replaced the MAF and Air filter. Also I don't know If it's related but I get a gas smell on occasion.
Thanks for any help or advice.

[newlife]

Originally Posted by boxsterg

CEL light is on again. Just got Durametric. It says P1128 Porsche FC 360 oxygen sensing adaptation idle range bank 1, P1130 PFC 361 Oxygen sensing adaptation idle range bank 2, P0159 PFC 23, sensor ageing behind converter bank (4-6)
Just got the durametric. Is there further diagnosis I can do to track this down? or what exactly does oxy sensing adaptation mean and what should I be looking for. I have recently replaced the MAF and Air filter. Also I don't know If it's related but I get a gas smell on occasion.
Thanks for any help or advice.

Hi

There is alot posted here re those two codes. I had an issue with those codes and CEL. After studing Wayne's book and his site and a few other web pages.

I did the following.......

1. Cleaned MAF sensor
2. Replaced air cleaner
3. Cleaned throttle body
4. Added a bottle of techron to my gas tank.
5. Checked for vacumn leaks (found none)

Now its been 450 miles later and still no codes or CEL. When i started studing those codes, it was confusing. Some may think its oxygen censors, but I'm not so sure... maybe... check out the codes and even google them. You will learn alot about them and will figure out how to troubleshoot.

Rod

[Dale_K]

Write down the values of the fuel adaptation range data points and post them. I think there are 4 different ones, One FRA and one RKAT for each bank.

[boxsterg]

Ok I'll get the values of the fuel adaptation range data. Thanks

[Dale_K]

Here's my thread on the fuel adaptation. In my case a new MAF sensor fixed the problem.

Bought the Durametric but I need help understanding the numbers

[JFP in PA]

Dale, did Todd ever identify the source for this information on fuel adaptation levels? Reason I ask is that I would like to read more about this for obvious reasons........

[paulv]

Originally Posted by JFP in PA

Dale, did Todd ever identify the source for this information on fuel adaptation levels? Reason I ask is that I would like to read more about this for obvious reasons........

JFP,

Did you ever see that TSB that Loren has? It's #0901 : "Actual Values Information to Aid in Vehicle Diagnosis" -- 6/19/09, total of 17 pages. Although it's for MY09, there still a lot of good info, e.g., RKAT, FRAU, FRAO, etc that helps me understand how all this stuff translates to conventional LTFT (which I already understand). The TSB is in the misc section, IIRC.

Regards,
paul...

[JFP in PA]

Thanks, I'll look into it............... Turns out to be very similar to the DME diagnostics section in the printed manuals set.

[boxsterg]

OK. Here are my adaptation range values:
FRA B1 88 B2 88

RKAT B1 3.89 B2 4.22
Any explanation or interpretation would be greatly appreciated. Thanks.
Garry

[paulv]

Originally Posted by boxsterg

OK. Here are my adaptation range values:
FRA B1 88 B2 88

RKAT B1 3.89 B2 4.22
Any explanation or interpretation would be greatly appreciated. Thanks.
Garry

Garry,

How many kgs/hr is the MAF sensor showing? Also, RKAT is the measurement when the engine is close to idle.

Regards,
paul...

[Dale_K]

The high RKAT values would seem to show intake leaks. The car is adding fuel in the idle load range, where the car is most sensitive to vacuum leaks. The FRA values are less than 1, meaning the DME is taking away fuel at higher loads. That's my interpretation based on the explanation of genuine expert in my thread with the link above. I'm not a real expert - just trying to pass on how it was explained to me. Here is a quote from the expert in my earlier thread....

"RKAT is the adaptation value near idle.
FRA is the adaptation value under load and further divided into FRAU (lower load range ) and FRAO (higher load range) ranges (perhaps the durametric doesn't display these divisions).

The RKAT values near idle are used to change the length of the injector pulse to account for deviations from ideality (ie intake leaks) to maintain the proper O2 sensor reading. The RKAT value is an additive factor and can deviate by +/- 4.5%. The FRA value is a multiplicative factor and can deviate by 1.32 to 0.70. The positive values or values greater than 1 increase the injector pulse length to account for a lean mixture, and negative values and values less than 1 are to compensate for a rich mixture.

As you might expect the RKAT values are most sensitive to intake leaks and would be greater than 1, adding fuel to account for the false air."

I found a vacuum leak on the oil fill tube in my car and another on the brake booster line. Some shops have a smoke machine to slightly pressurize the intake system, which lets them spot elusive vacuum leaks. Even after fixing the worst of the vacuum leaks, my car needed a new MAF sensor. Cleaning it didn't work in my case.

[paulv]

Dale,

I re-read your other post and was wondering if you ever checked the MAF voltage with just the ignition on (engine not running). From what I've read, it should be within the 0.9 - 1.1v range. Just curious.

Regards,
paul...

[Dale_K]

I checked the MAF readings at idle and they appeared to be "normal". It was confusing because I wasn't getting any MAF codes so I thought it had to be air leaks or fuel pressure problems. Finally I got frustrated and bought the MAF even though I didn't think it was the problem. At that point I was willing to spend $300 just to rule it out but I was totally surprised when all the adaptation numbers immediately went to almost perfect values. By that time I had recorded the adaptation numbers about 6 times so I knew the pattern and could see a huge change for the better. The CEL hasn't come back in almost 2,000 miles. My case might not be typical but it seems like MAF problems don't always generate MAF codes and a MAF can be bad even if seems to have normal readings. The Durametric paid off for me. Without it I wouldn't know that the data values had changed/improved.

I'm not saying you should buy a MAF because your readings are backward from mine. You could well have intake leaks since your car shows lean at idle.