RPM surging, rough shifting, overheating

[Heraclid]

Didn't get to deal with it yesterday, but should later today.

ICV is fine, in fact it's a pretty new one I recently put in. I periodically clean the usual places with carb cleaner. Air filter not great but not too bad. The water was low as previously stated, so I filled that up.

One thing you'd normally check right away but I hadn't checked because I check it pretty often? Oil. Figured that was fine. I check it often because I worry about it even more than usual with a VX for reasons we all know about. I've seen no indications of leaks. But sure enough, the dipstick came back practically dry. Will get underneath this morning and see what I can tell from that. So that's part of the problem at least. That makes me feel pretty stupid.

Seems intake manifold gaskets would be a good thing to look at too, will see. Never had to replace any, maybe I'm due.

Also found a little twist cap sort of like an over-sized one for a tire valve stem. Found it sitting between the rear edge of the hood and the driver's side wiper arm. Turns out it goes on the fuel rail on the driver's side, where there's a little valve stem that squirts fuel if you depress it. It's a miracle it ended up where it did and not lost forever down below.

Haven't been here in a long time, but it's been busy and the VX just won't cause me enough problems, LOL. Did have a melted electrical connection at the gas tank cause some stalling a while back. Also got a very slow power steering fluid leak and it's easier and cheaper to top it off every now and then than to replace the pump. Other than that stuff, just typical maintenance. Oh yeah (and this is a biggie for me), the window has never worked right despite all the "fixes" posted here. It dropped free into the door a while back because the adhesive holding the clips and glass together failed. Re-attached it but it didn't hold. Now if you use it at all the glass will come free of the lift arm and drop free into the door. But as far as getting me from A to B, it's done alright.

[VX KAT]

Oh yeah (and this is a biggie for me), the window has never worked right despite all the "fixes" posted here. It dropped free into the door a while back because the adhesive holding the clips and glass together failed. Re-attached it but it didn't hold. Now if you use it at all the glass will come free of the lift arm and drop free into the door. But as far as getting me from A to B, it's done alright.

For $65, strongly suggest you get the SBC metal brackets from Tim...can't believe the glass hasn't already broken.....and I bet it's much more than the cost of the brackets. Good luck, hope you can get it resolved.
http://www.streetboutiquecustoms.com/vx.html

[89Vette]

Seems intake manifold gaskets would be a good thing to look at too, will see. Never had to replace any, maybe I'm due.

That was one of my first thoughts too. But, after looking at the intake gasket set picture, it doesn't look like water (antifreeze) circulates through the intake manifold of a VX. Because it's running extremely hot, I would suspect antifreeze involvement because it creates lots of extra friction (when it gets into the cylinders) plus it burns hotter. (See if you see any white smoke when it acts up.)

As such, I might be more inclined to suspect a head gasket problem. Certainly water has to flow up to the heads. When a head gasket blows water can get into the cylinders and oil can get into the radiator (fluid). Maybe that's where your oil went?

You need to stop driving it until it get figured out. With the 3.5L engine history, this could lead to BAD news -- if you push it! (I could already be bad news.)

[Heraclid]

Thanks a bunch 89Vette - it is running fine right now, just for a couple of short trips. Plan is to get it to a good mechanic tomorrow for a thorough inspection. I thought I did see white smoke once, but I'm not even really sure and I didn't notice it the next time. But a lot of oil and water seems to have gone somewhere real quick, so that makes a lot of sense. I will mention your thoughts on this to the mechanic. Haven't even spent much time on it myself, things have been kinda crazy and now my brother's wife is in labor and I'm about to be an uncle.

[Heraclid]

Diagnosis was a faulty throttle position sensor, had it replaced. We'll see if that's really all there was to it. Still idling a little bit high.