Mine has been doing something similar, idling around 1200 rpm, shooting up to over 2000 rpm (sometimes well over) when in neutral or park. Surging while driving, seems to be mostly during deceleration coming to a light and such. Was sitting in line at a drive-thru and it was revving up pretty good and got way hot. One time it got real hot and also had really rough transmission shifts, but only once did that happen. Inspection showed some serious oil consumption and water was low.
Had erratic idle a while back but not the surging, etc. Replaced the IAC back then, problem pretty much went away until a week or so ago when all of this started occurring.
So anyway, a little over a week ago it started surging pretty bad then getting too hot. Got a CEL when it overheated, oil & water low, changed oil, added water, new air filter while I was at it. Checked PCV, sprayed IAC and throttle butterfly valve with carb cleaner. Have not done EGR though. Has not overheated or thrown another CEL since but still was surging. Problem is intermittent, may act weird right at start-up, drive great for 30 minutes of so, then start misbehaving. Some times worse, some times not at all. No apparent leaks other than a very slow power steering fluid leak I've known about for some time. Was advised to just keep an eye on it, shop was in no hurry to replace the pump and didn't seem to think it was a big deal.
VX was finally in the shop today and the code they got indicated a faulty throttle position sensor. Would be nice if that's it because it wasn't obscenely expensive ($40 part, though that is a lot for no more than it is). Since that was replaced this afternoon it is still idling a bit high, just over 1000 rpm, but if I shift it into drive while sitting still it settles to normal idle speed. Short little drives tonight yielded no surging though, will see how it goes from here.
I forgot to tell them not to use the windows, and it seems like mechanics always do. So the window glass came off the lift mechanism, dropping the glass free into the door. Since they made no attempt to make it right after doing it and I was sort of mad about that and would pretty much just rather they didn't anyway, I had to pull the door apart tonight and get it back in place. Got that down to a science now, done it plenty. It's a wonder the glass has not broken yet. The rubber in the forward channel is totally shot and needs replacement. I like using my windows and my main gripe with the VX is I've had mine since 2003 and the windows have never worked right. Really crappy design.
Reply With Quote