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I have owned the car since new, and from my recollection, very early on there was an issue with a rough idle. Almost like clockwork, after starting the vehicle (cold) and driving to the first traffic light just outside of my neighborhood, it would surge lightly while in D and with my foot on the brake. This has gone on for easily ten years, and I'm pretty sure the dealer didn't know or couldn't replicate the issue. Nonetheless, it was a minor thing and essentially I just ignored it, as it would only happen at most, once a day.
I don't drive the vehicle very often, but more recently (past few months) it's become much more noticeable. By noticeable I mean: happens more frequently, but probably mostly when the engine hasn't been running that long. Also, it's much more pronounced in terms of a greater surge while on the brake. If I kick it into neutral and blip the throttle, sometimes that will clear the problem. It's also worth noting that I have sensed a bit of hesitation, at times, moving from closed throttle to just opening it, as the vehicle moves from a stop.
No codes have been thrown. Is this a known issue? I took a look and I'm aware of other issues, such as motor mounts, which leads to a different type of 'rough idle,' but that's definitely not my situation. I can think of vacuum issues, coils and wires...and? Thoughts?
Check all vacuum lines for breakage/cracks.
Check the MAF - clean the sensor and monitor.
Do the simple rev test to check you motor mounts.
When was the fuel filter last changed?
I’ll inspect the lines and take a few moments to clean the MAF. I am dubious that it’s a vacuum leak. Hadn’t thought of the filter. Good idea. I’d have to look back at the records, but it has been years I’m sure. The motor mounts are not an issue. Never did have that funky vibration that others have had when they were broken. I am on my third set...
Hope to get to this in a week or so. Appreciate the suggestions!
Last edited by sesquipedalian; Jun 24, 2019 at 09:20 PM.
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