: serious question about my n*



99Classillac
01-29-07, 08:25 PM
Ok, I have a 99 deville. I posted a question about it making a hiss sound when it's at WOT in between shifts. Well today I was highway racing one of those new Maxima's and that hiss sound is now louder and it happens at all shifts instead of just between 1st and 2nd. The car feels faster but when I stopped at a light, I saw steam. I'm in NYC so it's cold up here so it could've been anything but I stopped and checked it out anyway. I left the engine running and popped the hood and smelled a faint trace of coolant. I got the waterpump replaced a year ago so it's not that. I read on here to do the bubble test on the coolant tank to see about head gaskets. So I took off the cap and the level was were it is supposed to be. I revved the engine by pulling on the TB thing. The coolant level came up and started to spill out a little. I let off the throttle and it went back down and bubbled a little and then stopped. It went back down to the right level at idle. I did it again and it started to rise again, I let off and it went down and did it's little bubbling on the way down. At idle there is no bubbles. When revved, there is no bubbles. Only when it's going down does it bubble. It bubbles until it gets to the right coolant level then stops bubbling. While I was doing this, I did not realize but a puddle of coolant was dripping out from underneath the coolant tank. More than what had spilled out the top. I put the cap back on and moved the car to get a fresh spot of concrete and revved the engine with the coolant cap on. I looked under the car and it was a very very small dribble. It seemed like it was just some dribble from when it spilled before and was just falling off the car and not really coming out of anything. My question to those who know is what is happening? Is my N* headgaskets going bad? Do I need to clean out the purge line or something? Where did all that coolant drip from when I revved the engine with the coolant cap off? I love my Deville to death and I'm never gonna scrap her. I'm not scared for it. I know I will fix whatever is wrong with her, I'm just scared of the $$$ it's gonna cost me. I guess I'm a hardcore Caddy fan because even if it's something serious, I'm gonna fix my baby and I'm still gonna go buy another damn one. I don't care what it costs me in the long run, I love caddy's. The pro's outweigh the cons to me. But any insight as to what's going on with my caddy would greatly be appreciated. Thanks in advance!


PS- I beat the Maxima. I don't know if he got scared of the speed or if my Deville is really just that fast.

Ranger
01-29-07, 08:48 PM
What you described sounds normal. The bubble test is to be done when cold. If done at operating temperature, the engine will likely overheat and the coolant will overflow. Surging with increased RPM is also normal. That's why it is called a "surge" tank. The drip you saw was probably from the coolant overflow you described. Some of it went down the overflow tube before it went over the filler neck. The small bubbles you saw where from the purge line and are normal. If the gasket was gone and putting exhaust gases in the cooling system, you'd be overheating, overflowing coolant and would see bubbles at idle on a cold start with the cap off. I think you have a bad case of internetitis. Relax and :alchi:

Not sure about the hissing sound. Could be a vacuum leak. Does it idle OK?

99Classillac
01-29-07, 09:02 PM
Glad to hear the car is ok for now. As for idle, yea it idles perfect. In my last thread about the whoosh/hiss sound, someone said it could be a kink in the exhaust or my cat is falling apart. It idles perfect though and doesn't miss a beat when I hit the gas for a WOT run. It just hisses like I got a badass turbo under my hood everytime it shifts gears. Sounds cool kinda cuz you can hear it in the car and outside of the car too. My brother commented on it to my once. It sounds like a turbo wastegate openin up to dump the excess psi. It's loud but it makes my car sound fast, kinda like a ricer wants to do to his car.

Ranger
01-29-07, 09:14 PM
Ack, last thing you want is your Cadillac sounding like a ricer. Wish I could help you on that hiss. No leaks? Can you hear it if you rev it in neutral? Since you are in Staten Island I doubt that a rattler has taken up residence under the hood.

99Classillac
01-29-07, 09:39 PM
I was thinking maybe there's a leak in the intake but then again the guy on the other thread said it may be the exhaust system. It doesn't make the sound in neutral. It only does it when it is in between gears and I let off the gas in between the gears from a WOT.

Ranger
01-29-07, 10:19 PM
If it was exhaust or intake it should make the same noise. Maybe it is in the trans.

chazglenn3
01-30-07, 08:20 AM
They actually sell a "blow off valve" to the import tuner crowd that does just what you describe. Did you recently purchase the car, and if it has done this since you bought it, I would look for one of these aftermarket "improvements". Here is an example:

http://cgi.ebay.com/ebaymotors/TURBO-BOV-SOUND-on-N-A-Blow-Off-Valve-Horn_W0QQcmdZViewItemQQcategoryZ33742QQhashZitem26 0081222323QQihZ016QQitemZ260081222323QQrdZ1QQsspag enameZWDVW

99Classillac
01-30-07, 08:28 AM
No I owned the car for about 3 and a half years now. The guy who owned it before me was a old guy in Tennessee. I doubt he would have done that to a caddy. I hope it's not the trans. It'll make a sound like that?

By the way, that fake turbo thing on ebay is retarded. Ricers are retarded for buying that crap. Who wants to have the sound of a turbo and not actually have one, so you can talk trash and then get your a$$ handed to you in a race. Typical Ricer.

AaronZ34
01-30-07, 10:40 AM
It sounds like a turbo wastegate openin up to dump the excess psi.

Not that it really matters in this discussion, but that's not how a wastegate operates. Wastegates bypass exhaust flow around the turbine, thus only allowing the turbocharger a certain amount of exhaust volume, which controls how fast the turbocharger spins, thus controlling how much air the compressor can flow, thus controlling boost pressure.

Dumping excess pressure is controlling boost via bleeding, and it is loud, inefficient, and is dangerous to the turbocharger/supercharger, as well as your engine.

Ranger
01-30-07, 11:10 AM
No I owned the car for about 3 and a half years now. The guy who owned it before me was a old guy in Tennessee. I doubt he would have done that to a caddy. I hope it's not the trans. It'll make a sound like that?

By the way, that fake turbo thing on ebay is retarded. Ricers are retarded for buying that crap. Who wants to have the sound of a turbo and not actually have one, so you can talk trash and then get your a$$ handed to you in a race. Typical Ricer.
Not sure. Using the process of elimination, if you can't duplicate it in neutral, that (may) take the engine out of the equation, unless it has to have a load on it to duplicate.

chazglenn3
01-31-07, 12:52 PM
No I owned the car for about 3 and a half years now. The guy who owned it before me was a old guy in Tennessee. I doubt he would have done that to a caddy. I hope it's not the trans. It'll make a sound like that?

By the way, that fake turbo thing on ebay is retarded. Ricers are retarded for buying that crap. Who wants to have the sound of a turbo and not actually have one, so you can talk trash and then get your a$$ handed to you in a race. Typical Ricer.

I totally agree with you. While I am glad that the car isn't "equipped" with one of those things, I am also, like everyone else wondering what it could be.

dkozloski
01-31-07, 01:27 PM
Stand behind the car while somebody hits the gas a couple of times. If the exhaust is blocked or kinked it'll sound like a big air hose.

Is this noise loud or subtle?

99Classillac
01-31-07, 04:54 PM
The noise is pretty loud. But it only happens under load during a WOT when it shifts gears. Just as it shifts gears, it makes the loud hiss and then it changes gears. It seems like when it goes from high rpm to low, as in a shift, it does the sound.

Eldobroken
02-02-07, 01:37 PM
If it was exhaust or intake it should make the same noise. Maybe it is in the trans.
Dude hate to say it but 00 ETC was doing the same thing I just got it back. The pistons were wasted in the tranny. Funny thing was it worked fine but had developed an axle seal leak. Long story short $4000

99Classillac
02-02-07, 09:05 PM
Are u serious? Jeez. Did it throw any codes? Can I keep drivin it or is it gonna grenade on me?

Eldobroken
02-03-07, 07:47 AM
Are u serious? Jeez. Did it throw any codes? Can I keep drivin it or is it gonna grenade on me?
I hope it does not for you. Mine did not throw any codes the check engine came on once but it was not related it was from the map sensor. Anyway I would get it checked.

99Classillac
02-03-07, 10:09 AM
Yea I guess I gotta take it to a shop. I don't really wanna take it to the dealership but I don't trust Aamco either. Those guys are quacks. Was your trans totally rebuilt?

chazglenn3
02-03-07, 12:16 PM
Are u serious? Jeez. Did it throw any codes? Can I keep drivin it or is it gonna grenade on me?


If I were you, I would lay off of the wide open throttle blasts until you get the problem resolved. Stressing the parts unnecessarily is probably not a good idea.

Eldobroken
02-03-07, 02:59 PM
Yea I guess I gotta take it to a shop. I don't really wanna take it to the dealership but I don't trust Aamco either. Those guys are quacks. Was your trans totally rebuilt?
First I took it to a local Gibraltar shot they screwed me totally and it kept leaking. Then i took it a father away shop that a friend of mine has worked there for 12 years. I had it totally rebuilt runs great so far. My friend just does the torque converters there. He said they only use the converters for the Arora 4.0 N* supposedly the same thing and half the price he said. Runs great so far and I have had it up to about a buck and a half. Figured i might as well hammer it while it is under warranty.

99Classillac
02-03-07, 04:22 PM
Lol, yea take advantage while u can of the warranty. I would. But watch out, 1 mile past the warranty expiration, you trans will quit. Always happens like that for some reason. I found a place that sells rebuilt caddy transmissions for $1250. They'll give back $550 for the core. I figure that's better than payin some jackass who can't do right to rebuild it for me. Only thing I'm gonna miss is I really wanted my car to be an all numbers matching car. Oh well. In 30 years, I'll kick my ass, but for now, I need to save $$$.

Eldobroken
02-04-07, 10:24 AM
Lol, yea take advantage while u can of the warranty. I would. But watch out, 1 mile past the warranty expiration, you trans will quit. Always happens like that for some reason. I found a place that sells rebuilt caddy transmissions for $1250. They'll give back $550 for the core. I figure that's better than payin some jackass who can't do right to rebuild it for me. Only thing I'm gonna miss is I really wanted my car to be an all numbers matching car. Oh well. In 30 years, I'll kick my ass, but for now, I need to save $$$.
This shop used all GM parts so it will still number match. Tranny feels real good and supposedly the rebuilder is top notch. we will see 1 year 12k mile warranty on it.

AlsDeville
02-07-07, 01:30 PM
Sounds like it might be the accessory drive belt slipping when the rpm drops. At high rpm the tensioner has a hard time taking up the slack when the rpm changes abruptly. If the belt slips, it makes a nasty screeching noise. If the belt is old and hard, It may not be up to the job.

On another thread, someone sugested putting a breaker bar in the tensioner to loosen the belt to check for bad bearings in the accessories. If the bearings are making noise, it should go away when you release the tension. When i tried this on my newly purchased 03 Deville, the belt screeched like a banshee.