Alright, my car's been acting up a lot lately, just wondering if anyone could give me a clear-cut yea or nay on if my motor (S4 if it matters) is going out or not. Here's what's been going weird:

- Car sometimes will not start if it has been sitting for about an hour and a half or so. Car starts normally in the mornings and starts pretty normally when the engine is fully warmed up.
- Three times in the past week, the temperature gauge has gone up to about 3/4 of the way (!!!), and today when I stopped at a gas station, when I turned off the car, the coolant overflow bottle cap popped off and the car dumped about a quart of coolant on to the ground. When I limped the car home (1-mile trip), my e-fan did not turn on, although it was on before I stopped at the gas station.
-Coolant buzzer goes off every now and then, went on one week after I topped off the coolant.
- I checked the compression when the motor was cold, and it read at 110psi front and 110psi rear, still have not checked the compression while the motor is warm.

Any speculation is welcome. Thanks.

 

Compression sounds fine, even when cold, but your coolant seal might be shot.

Pull off the coolant filler neck cap and have someone crank the engine (with EGI fuse pulled so it wont start) and look to see if there are any air bubbles surfacing. If you get some bubbling action then your seal's probably shot.

Does your car smoke at all hot? Cold?

You said you have an e-fan, well the reason your gauge is going up to 3/4 might be because it is either not working properly, the thermoswitch isn't working properly, or it's not set up properly. Which fan and thermoswitch are you using?

 

When my car is cold it steams a lot, so lots of white "smoke" when it's cold. It doesn't smell particularly sweet, though.

It could be a faulty thermoswitch controller, which would explain why sometimes the fan clicks on when I start the car cold in the mornings. It's just the one that I ordered with the black magic kit.

 

Thought so. I used to have a black magic thermoswitch and it crapped out on me the exact same way as that. Afterwards I searched a bit on the forum and talked to some people and they had the same issues with the black magic thermoswitch. If you'd like to try something ditch that thermoswitch and order the generic electronic one from JCWhitney (that's the new one I'm running) or some other generic one from somewhere else and hook that up and see if it works better. You can also try getting rid of the thermoswitch completely for now and running it with the fan on all the time so you don't overheat anything.

Also try the bubble test I described and see what happens.

 

I'll be sure to do the bubble test, thanks a lot.

 

No prob, hope your engine ends up being fine.

 

thats how my motor started... well now... well... yea.

 

I did the bubble test, and no bubbles surfaced, but my coolant level rose about an inch, almost overflowing from the filler neck.

 

k.. remember surging coolant is bad. rising an inch is... still not terribly normal. you may have a small leak. the only thing i can tell you is try getting a new rad cap. that may be causing coolant loss. remember, if you ever open up your rad cap when the car is cold, and its pressurised... coolant seal

 

It's a coolant seal

 

If it was a coolant seal you'd know.

BTW forgot to ask, except for when your overflow bottle filled up like crazy were you losing coolant regularly? Like did you continuously have to fill it up even with the overflow at normal level?

 

try pressure testing the system to see if yuo are losing any coolant also and if you are pull the plugs to be sure it is not going into the combustion chambers...

if you find you have a blown seal, remember i do rebuilds.

 

Only once or twice, whenever it was me who wasn't in charge of filling up the radiator, so someone filled it up in the wrong manner. I guess my motor is fine, I think it only has about 55k or so on it.

 

Check the plugs for rust or similar. It's very likely it's a coolant seal, that's a very typical indicator, and not all of them will bubble either.

 

The plugs are pretty much brand new, and they weren't rusty the last time I pulled them.

 

Only way to know for sure then is a coolant pressure test.

 

This is like doing the test only half way.



Start the car, when it's cold, with the rad cap off. Let her idle. Now watch it. The coolant level may rise and fall, but if the seals are okay it won't overflow much (if at all.) A few bubbles are nothing to worry about, either. Stop worrying about your seals.

But, if it geysers like Michael Jackson at a Cub Scout Jamboree, it's rebuild time...

 

You can have a bad seal even if it doesn't geyser, then water just slowly seeps in when it's left sitting, and eventually will start to make your plugs form rust/etc, and eventually you'll end up with the car acting like it runs on one rotor until all the water is pushed out, then it'll come back to life and you'll be good.

 

LOL

 

My car has different symptoms but I think it's a similar sort of problem. First off, it's about 20 degrees here which seems to make everything worse. It all started out with a little smoke when the car was warming up from a cold start but it went away fairly quickly. A few nights ago I got into my car and started it up and it turned over, revved up to 3k and then dropped like a stone to 0. Now, whenever it's colder than 35 degrees it almost never starts. In the rare times that I can get it running, I let the engine warm up and then go to drive it. The engine feels fine until I try and push it past a third throttle and then it feels as if there is no power whatsoever. Are my apex seals done or could there be another problem?

 

First off, stay open to the possibility that what is happening is due to several small problems instead of one big, far-reaching one.


A little smoke or a little steam? Did you get a chance to smell that steam? Next time it happens, give it a sniff. That'll tell if a) it's just steam or b) maybe a little burning oil or c) coolant (sickly-sweet smell.)

The first place to look if your starting problem is temperature related is the water thermo sensor. It's just below the mounting bolt/bracket for the alternator. This sensor tells the ECU what temp the coolant is, and thereby what temp the engine is. When the ECU stops getting a signal from this sensor (if it's broken or disconnected) then the ECU defaults to a 'hot' air/fuel mixture. On a hot day, it doesn't make much of a difference. In winter, it makes the car nearly impossible to start.

What is a "third throttle"?

Your apex seals? Do a compression test to eliminate (or affirm) this one.