HELP! 1997 Q Overheating and High Idle at 80 mph

[blackqguy]

Hey guys. I just purchased a used 1997 Q45 and while driving at 80 mph, I noticed that the car was idling very high (4-5000 rpm). I also notice that the temp gauge was at the max suggesting that the vehicle was over heating. I let the vehicle cool and once it was at a normal temp, I resumed driving with no problems. The day before this occurred, the coolant was low, so I filled it.

Has anyone experience this problem. Additionally, is there a correlation between overheating and high rpms? I'd appreciate any feedback provided.

[cccpman]

The Q won't just overheat on its own, plenty of people regularly go for 120+ mph spins in them without problem. If your coolant is low again then you clearly have a leak, possibly a radiator leak, or just a hose. Check the levels again, you just bought the car so it may not have been filled up by the previous owner. Now that the car has overheated you may have killed the Knock Sensors along with a couple others, however since you shut it off on your own (and it didnt cut out) you could have skipped by

The high RPM idle is what really could help solve this problem. Your car is newer then mine, so you could always go to an auto zone or whatever and have them read the ECU codes for free for you (they do it here). If not you can count the flashing lights by turning the ECU to diagnostic mode (search feature). It will probably give you a code 34 - meaning bad KS (if the heat killed them), and another code (which will help determine why it idles so high, BTW it could just be going 80 there is some wind resistance and it has to keep pumping gas in there - what is the idle at idle being 0 mph, give it a few seconds to level out if you must, that will tell us a lot also)

Welcome to the Q45 family, great cars and great people. You just have to do that little bit of work to restore the car. Good luck with your problem

[paranoidjack]

Depending on how long the car was overheating (you say it was AT the max, which indicates it was overheating for a little while), you might consider returning the vehicle to the dealership you bought it from as I'm sure you have some sort of warranty. Overheating can case some serious damage, and "normal driving" afterwards doesn't mean small leaks aren't formed!

[Skibane]

Excessive engine speed for any given vehicle speed means that either the transmission is slipping, or is in the wrong gear. There really isn't anything else that could cause what you're describing.

[greenwar]

at 80mph my FGY33 will rev at 2500 - 2600 if I am not wrong. Was your OD engaged? in 3rd gear it might be going to 4-5K rpm however I never tried that.

Overheating could be because of bad radiator or even worn fan clutch as well as the other things the gentlemen above mentioned. Return the car if at all possible other wise I would do the following. Gurus please correct me if I am wrong:

1) drain coolant and put new2) check fan blades for crack3) check fan clutch - I think this can be done after the car is at norm temp - SHUT the car DOWN - then try to spin the fan with your hand - if it spins freely fan clutch is probably in need of replacement. 4) If none of this is the problem - check for bad thermostat - take it off and boil it in water to see if it opens - or just replace it.

Hmm, what else? I am a novice and fortunately never had to deal with overheating car. Gurus please add your steps.

[blackqguy]

As I stated previously. This occurred after driving the car for ten minutes and after I allowed the engine to cool, I've had no further problems with high rpm or overheating. This was several days ago and I drove the vehicle on the highway for 2.5 hours as I was out of town. I bought the vehicle very cheap from a friend, but plan to take it to T3 in Atlanta to get it up to speed. Thanks again guys!