Gus B.

I know I've mentioned before the rough idle when I first start the vehicle after refueling (when the tank has 1/4 left or less) and only for the first 10-20 seconds, but yesterday, after having filled the tank two days ago, I went for a "10 minute spirited drive", parked the car for 20 minutes, and upon restart, rough idle for 5-10 seconds. Drove slowly for 20 minutes, parked it for 2 hours, and upon restart, again rough idle for 5-10 seconds. Drove it slowly for 5 minutes, parked it for an hour, and again, upon restart, rough idle for about 5 seconds. Went to run another errand (that is what Sundays are for...) and no rough idle upon restart. No lights ever on the dash and everything works perfectly at all times, except for the first seconds after initial startup.

Any clue as to what is going on? Never had this happen before (besides just after refueling).

jaustin

did you try and pull codes to see if you have anything pending? How are the spark plugs? Coils, Fuel filter?

Gus B.

Don't have a scanner, so unless I pay $50, not going to see any codes. If this odd behavior is still present, will take it to the local indy and see what he has to say about it. Just wanted to go in there having a better idea about what could potentially be causing this.

As per the service receipts I got when I purchased the vehicle, plugs and coils were changed back on June 2021 and the vehicle has been driven ±17K miles since, so I doubt it could be those based on mileage. The odd thing is that the fault is only present for 5-10 seconds upon startup, but then disappears and all works perfectly fine. It has been documented that post refueling, some fuel vapors get trapped and causes this odd behavior upon startup.

Haven't seen that the fuel filter has been replaced.... Will add it to the list of jobs to be done when I take it in for regular service.

garrett376

You need a scanner if you want to own one of these cars.
Often the camshaft lifter solenoids start to stick as they age, and the result is a very rough idle with misfire codes for an entire bank. But again, without a code reader, any and all thoughts/comments are a shot in the dark.

Gus B.

Guessing scanner time it is...

Any preference on the vs.

jaustin

I have the icarsoft and it has worked good for my needs. I think I bought mine off ebay for 80$ new.

Gus B.

Thank you. They do look quite a bit different these days after polishing them due to water stains. See post #73 for final results.