Jim in Tucson

iTrader: (3)

Now that I'm on E85 I am getting occasional P0300 Random Misfire Detected. I don't feel anything. Does not seem predictable at all. I never had this on gasoline.
New plugs gapped tight at 0.020".

Any ideas? Is this simply coincidence?

skiracer

iTrader: (1)

"The Check Engine Light is a DSM badge of honor. It means that your car is fast!"

Mike W of RRE

RazorLab

iTrader: (8)

What kind of timing are you running at cruise and idle?

[EVO]Cookie

iTrader: (3)

I had the same thing happen when I first switched to e85. It ended up being a lean condition at idle. I could be rolling up to a stop and have it pop up. I run my Idle rpm neutral and idle rpm drive no less than 1K. I think it's a little more common with cams and bigger injectors if your timing is to low. I run no less than 11* at idle. I have the RC1000's and 272 cams they don't like stock timing.
If your trims are spot on try some timing and do some logging.

Jim in Tucson

iTrader: (3)

Bryan, at cruz I'm at 38* and at idle it's 15*. Idle is set at 991rpm.

Jim in Tucson

iTrader: (3)

You may have hit on the cause. I had the idle at 1,000 and just recently set it back to OEM. I've now put it back at 1,000.

RazorLab

iTrader: (8)

Do you have a freeze frame of when the CEL was triggered?

Jim in Tucson

iTrader: (3)

Not exactly sure what you mean? Do you mean a data log?

PeteyTurbo

iTrader: (9)

yeah he means a log of the instant the code was set off, so you can see what all was going on at that exact point in time..

RazorLab

iTrader: (8)

OBD2 stores information on what was going on the instant the CEL was triggered.

If you use scantech you can see this information.

draconx

iTrader: (6)

LMFAO!!!!! oh man thats awesome!

skiracer

iTrader: (1)

I've received P0300 codes previously and seemed to happen in low RPM or idle situations. It dissapeared recently, didn't do anything different with the tune.

Jim in Tucson

iTrader: (3)

Mine is getting worse...

I'm getting the dreaded P0300 everyday, sometimes 2-3 times per day. I would not really mind except that whenever I have a "code" the CEL blink-on-knock functionality is DOA.

Jim in Tucson

iTrader: (3)

Just thought of something...

I'm turning off closed loop by setting the load switches to all zeros. Is that a bad idea? Could that cause or exacerbate a lean-at-idle condition, especially at drop-back-to-idle situations?

Maybe I'll try going back to closed loop for idle, but retain open loop for cruz? I doubt I'm actually wasting much fuel at idle anyway.

Comments welcome...

PeteyTurbo

iTrader: (9)

Try pullung back some timing at idle, Thats way higher then what I am running..Also what rom version are you running?