I am leaning toward having a Porsche bonfire!
OK, do you mean by AFC, the Intake Air sensor? Your question is not random at all, that is one of the items in the chain that could suffer failure. I appreciate your input!
What you are describing sounds as though it's similar, on my drive home she actually started her issues again... as I slowed for traffic on the highway, depress the clutch... poof! Engine dies, when I got off the highway, she was doing all her usual spluttering, smoking and no idle. The problem does seems to diminish when I get the RPM up, however that is difficult to tell because she is overfuelled, so there is still a certain amount of smoke! So once again not dissimilar from what you describe... however here is what we have done again, with some additions, you'll see we actually checked and rechecked and re-substituted that Intake air sensor (Air Flow sensor) with a reconditioned one.
The problem
- The engine is running rich, no idle, smoke and all round pain in the a$$!
We looked at
- Grounding on wires and general connectivity. Found to be satisfactory.
- CHT sensor checked found sattis but replaced nonetheless!
- No significant vacuum leaks.
- Ballast resistors were swapped out with known good ones, originals found to be sattis.
- The main/double relay was clicking more than it should but it didn't have any effect on the car's running.
- Fuel pressure was a little high at 40 psi without vacuum on the regulator. Installed an adjustable unit, it went down to 20 psi and still the same performance issues.
- The cold start valve was checked... ran a separate fuel line around the cold start valve to make sure it wasn't pouring additional fuel into the engine. Found to be sattis.
- Substituted three different ECUs, Original found to be sattis.
- Throttle body itself was examined and was found to be sattis.
- Checked the throttle position sensor (to make certain it wasn't giving the full throttle signal) - found to be sattis.
- We replaced the original Air flow unit, subsequently, Bill even swapped in a second one - Still no bloody improvement!
Bill's question
- "What I have determined is that all four injectors are firing at EACH ignition event and to my understanding they should all four fire at EVERY OTHER event".
Do you think that could be indicative of the problem?
With the money I spent thus far, I could have performed a carb conversion! My head still hurts, and I know for a fact that Bill is about to take her out back and set her on fire, if I don't!
This car is becoming the bane of my existence! I am studying and need transport, now I am stuck spending money I can't afford to spend on a car that's just not co-operating!
Bill, do you think we should consider a carb conversion? Do you have some old carbs and manifolds lying around? Otherwise we may have found a use for all the combustibles in your shop!
I'll see you on Monday.