Rough idle (low rpm) during cold start - New feul blend issues reported

[jackmac]

Rough idle (low rpm) during cold start - Issue with new fuel blend reported

After a 2nd service appointment and reflash of the ECU, I was told today that there is a new known issue with the recent ethanol fuel blends (or switchover to summer blend?) that were introduced recently causing rough initial idle and low rpm. I have LR3 HSE with 4.4L V8.

Dealership indicated today that they have at least 15 customer reports, and that the regional rep was onsite yesterday. They are collecting VIN's and customer info, and anticipate a TSB will be forthcoming, and possibly a software ECU update to address the condition.

Just curious if anyone else on the board is experiencing this problem too. I only have it during cold starts in the morning. For the first 5 or 10 seconds, the RPM bounces around below 1000 RPM (dips as low as 400 briefly), then settles into normal fast idle. It is really just a minor issue from my perspective, and I'm sure a fix will come soon. Should also mention that it did illuminate the check engine light prior to the 1st dealer visit earlier this month, but has not returned so far since the ECU reflash.

Thanks,
JackMac

 

[DonA]

I have this issue with my 05' V8 SE

I suspected it was the ethanol. I usually fill up at the same station and when they switched from MTBE to 10% ethanol the rough cold starting problem started the next morning

My guess is they will have to richen up the cold start tables a hair