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Idle lag/stumble

3551 Views 7 Replies 4 Participants Last post by  XR650R
So I had an interesting event yesterday. After work I went to get a carwash, it's too cold here to wash by hand still, and right before the dryers kicked in my car started to lose idle RMPs. I normally idle around that 1000-900 area but the car dropped to 500 and came back up, back down and back up and down once more to where I thought it would stall out. I had it in neutral and was just sitting there at the time. When the door went up I didn't even dry the car, I just went to the parking lot and sat. I did manage to catch it doing it again. Went from 900 to 500 back up then down to 700 and came back. I decided I needed to get it home and it hasn't happened again.

Anyone else have anything similar happen? The closest thing I could find was after filling up with gas but I didn't fill up yesterday. This morning on cold start it ran fine but I did notice when I got to work it seemed to idle low and was around that 700-800 range.
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I did manage to catch it dipping to 500 when I pulled off to the parking lot. I've been watching it but is hasn't done again really. I planned on going soon because a horn connection is also starting to go I think, have a video of that too. Won't beep when you lock it and when you start it and try to honk the horn you can hear it click until it decides to make a noise. Comes and goes unfortunately.
So update time. Last night I went for a wash and got home just fine. This morning on the other hand..... not so good. Pulled the car out the garage and it idled up and down until it idled so low it shuttered and stalled. I got my phone camera ready and started it again. Idled fine and then idled up and down until it idled down to 300 shuttered and stalled out. Started again and kept it going to get to the dealership. Got a block away and had no power in 2nd. Flicked the gas with the clutch in and started on my way. Could notice some power, no power, power in some spots will just normal driving. I got about a block away from the dealership and it was running fine. Parked at the dealership and watched it idle just like it normally would, no jumps or dipps. Went in and showed a tech the videos I had and talked it over with them. I also have a horn that doesn't like to work when its cold out, also very safe. Of course the horn works now because it warmed up but I had video of that not working. They might get to the car today, if they don't have time today it will be first thing tomorrow.
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So update:
Probably should have provided more background. I have the injen intake installed and have had this on for probably 2 years now. This problem didn't occur until after my dp and exhaust upgrade. The first post was after I went through a car wash with all three components for the first time.

Dealership basically said they think I sucked in enough moisture to through the sensor and make it freak. Kinda makes sense, because of the exhaust upgrade I could have just enough extra air flow that I hit the tipping point of water being pulled in.

My thought on the second occurrence is I may have been good if I would have drove a little bit and any moisture when have evaporated. Instead I went straight home and the car sat over night. Any moisture froze and when I started up in the morning, water was reintroduced.

So I serviced my filter to make sure it good and I am waiting for a hydro sleeve to try.
Two questions for anyone
1) does anyone have a problem going through a car wash with an open intake (like injen w/o a box) and exhaust mods
2) when you do go through a car wash, do you leave your car running
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