Actron CP9110 and STFT/LTFT

[repinS]

Just got some exhaust work done earlier today, got a new front pipe and cat. With a new donut gasket and a fresh cat that wasn't falling apart internally, the ticking under boost I've had for a long time has disappeared. I was under the impression that this was the cause of some of the false KR I've been getting, about 2-4* at WOT. I originally thought the problem to be manifolds, but that doesn't seem to be the case. So, just took it for a run tonight in 21F weather and without the ticking, I'm still getting the same 2-4 degrees of KR. The car pulls as hard as it ever has, and it seems to be independent of temperature. Winter or summer, it's been the same.

My (PeterG's... dude, I realized I still owe you $ for this. We need to meet up) Actron CP9110 LTFT and STFT are both jumping around in the 120 to 130 (128 stands out in my head for LTFT) range according to the scanner - I'm not quite sure what this means, but it doesn't strike me as an extreme condition, considering it's always there and doesn't throw a code. LTFT/STFT will be this way even taking it easy around town without KR, and at idle as well. O2 never shows a lean condition while doing the high RPM pulls.

I have noticed the occasional Knock Sensor count bump up even at idle, especially in the few seconds after startup.

I can't really explain the odd behaviour. I'm bone stock except for an intake. Another example of a freak 1995 PCM? Do I need to drive around more to have the PCM "learn" the new exhaust conditions?


edit: Might I also add, the PCM always throws a "code" of a Quad Driver fault but will never show a light, even after resetting each time.

[willwren]

I'd have to look up numbers to get it straight in my mind before answering, and I will if someone doesn't beat me to it.

In the meantime, do NOT put your foot on the brake with the scantool hooked up. It will throw a QDM fault.

[J Wikoff]

128 is what the PCM wants. Higher numbers means it's adding fuel, lower means it's taking it away. Staying in the 120's is fine.

[PRD2BDF]

In the meantime, do NOT put your foot on the brake with the scantool hooked up. It will throw a QDM fault.

So that code, QDM, is just a nice way of saying "You're an idiot for using the brake with a scantool"?

[willwren]

Much more complicated than that, but in this case, it's a known bug with the cp9110 and our cars.

[repinS]

Sweet, thanks guys. Been snowy the last couple days, so no more test runs for the next couple :(