Idle problem question

[goblue]

Merry Christmas everyone,

I'm having an idle issue for the second time, and I'm wondering whether it might be caused by a shady gas station. Here's the story:

I live in VA, mom lives in Jersey. I drove up a month ago, filled up at a gas station (93 octane as always) and afterwards noticed a rough idle...RPMs would go up and down, lights occasionally dim for half a second, and car tries to stall (and a few times it did). This was only a problem when stopped and idling--car seemed completely fine while driving. This happened for a few weeks (I had filled the tank in VA since then), adding fuel injector cleaner did not help. The second week my check engine light came on--engine running lean. Took it to a shop and after they cleaned my air intake system and put some sealant in the vacuum hoses everything worked perfectly.

Now I'm back in NJ, filled up at the same gas station, and right away I'm having the same exact idle problem. I never thought it could have anything to do with the gas or this gas station, but it seems like quite a coincidence. Is it possible that this place is doing something shady with their premium gas and that is what is causing my idle problem? If so, any thoughts on what I can do about it? Octane booster? Any advice would be greatly appreciated.

Thanks,
Rob

[EvoEatr]

What year is the vehicle? How many miles are on it? That is an odd coincidence, You could try some octane booster. however I doubt thats your problem if you mentioned you took it in and they fixed a vacuum leak. There are a couple things I would be checking. Do you notice any loss of power? are you hitting target boost? Is the CEL illuminated now? or even if its not do you have the ability to pull codes from the ECM? I would clean your MAF sensor and also test to see if its bad ( with the engine running tap on the MAF with your fingers and if the engine stumbles or dies than you have a bad MAF). Also with the engine running take a can of 2+2 gum cutter and spray around all vacuum/boost lines and intake manifold gaskets, if you notice the engine idle change you have found a vacuum leak. Also if the vehicle is has somewhat higher mileage than I would think about cleaning the throttle body, I have seen MANY MANY carboned up throttle plates cause idle fluctuations and odd CEL codes before. As said though if you have a scanner and can check the ECM you want to start there...

[EvoEatr]

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