Quote:
Originally Posted by XfireZ51
....snip...
If it is O/L as you point to here, then the O2 has nothing to do with it.
|
I'd agree with that. But please note in my post. The Open Loop suggestion was about speculation of fuel and is a separate paragraph.
The second paragraph introduces a separate suggestion (topic) and does not imply fuel or Open Loop.
Quote:
Originally Posted by XfireZ51
Whatever the fueling issue is dependent on the base VE table(s). In O/L, the O2 isn't causing the ECM to modify the fueling.
|
See paragraph issue above.
Quote:
Originally Posted by XfireZ51
Having spoken to Lee about it, it appears to happen in cooler weather and before the motor is up to temp. It doesn't go into C/L until about 75C CTS.
|
I didn't speak to him but the OP said
Quote:
Originally Posted by LGAFF
Having an issue, when I first start driving my 90, the car will miss and sputter for a short time(10 seconds) then run fine, no related codes..... as the exhaust is poping its unlikely fuel.
....snip...
|
He also mentioned that the car stalled and died once. Does your cal get run only after the first 10 sec or so? Could the problem be something outside the cal table? Could the MAP vacuum line have oil in it? And gurgles free? (sucked out) Or could it be a massively leaking injector whereby the excess fuel causes popping in the first 10 sec while being burned off?
Quote:
Originally Posted by XfireZ51
I know that since its my calibration he's using.
|
I see
Quote:
Originally Posted by XfireZ51
And because he's using a copy of my cal, I also know that it's likely a bit lean since his motor has both larger intake and exhaust cams while my cal is for a larger intake cam only.
|
I see, so because he's using your cal and the car has not been tuned it runs rough for the first 10 sec or so?
Quote:
Originally Posted by XfireZ51
.... snip... And I know Lee's car has not been tuned properly for driveability. Given the specific conditions of Lee's problem,
|
I agree driveability is important.
Quote:
Originally Posted by XfireZ51
I suspect the cal needs to be tweaked. To me this seems to explain what is being observed in a manner much simpler than a flaky O2 sensor. Especially if its happening in O/L.
|
Sure would be a shame to spend a lot of time tweaking the cal only to find a failure in vacuum or a sensor or injector. While it is doable to fix or hide a hardware issue in software you can end up chasing your tail.
I'd agree with your assessment of O2 sensor if it's Open Loop only. I wonder though if it really is open loop only? Still the the reported issue goes away in 10 sec. Sounds like he needs to try a different chip (of any kind) to see what happens in that first 10 sec. Grabbing and using the most obvious symptom like the 10sec one seems wise.
The goal is to help get the car fixed. A step by step "what to try next" is in order. I'd say the next step has to be gather more info/symptoms.
Possibly attach a data logger if possible.