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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.
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