Where's the smoke coming from??

[ryan.hess]

I just can't seem to figure this out... I have steam/burnt coolant smoke coming from roughly below the transmission dipstick area after the car has warmed up. Obviously, I don't want a fire, so I need to figure out where the coolant is coming from. Where are all the locations of the heater hose on a GTP? I see one line coming from the intake manifold and going into the car next to the brake booster... I see another from the plenum to the radiator junction at the front of the car... None of these are leaking, so there has to be one underneath everything that's dripping on my exhaust!! WHERE IS IT!?! HELP!

[robby1870]

could be a head gasket or lower intake gasket

[jmgtp]

I wouldnt really worry about a fire as coolant inst flammable. Steam, a mess, and a horrible smell is the worst youll get. I guess if you ran it bone dry without coolant things could possibly get hot enough to burn something but I think the engine would quit running before that happened. Theres lines that run into the throttle body from underneath. Suspect those, especially if you have removed the plenum recently. Coolant from there would drip right onto the crossover pipe and boil off making a steamy mess. Otherwise theres the line going into the firewall by the brake booster, it leads to the heater core. Then theres a metal line that runs from the water pump down the passenger side, you could just follow that, it tends to rust and leak, but I cant see where it would leak onto anything hot enough from there to boil off and make steam.

[ryan.hess]

I think at least for the lower intake, there would be a puddle around the distributor area... but there isn't. I checked the vacuum, and it's pulling a steady 14" (seems a little low, but it's steady is the point) so I don't think it's the head gasket. Plus it runs too darn good.

[robby1870]

14" does seem low.......I think closer to 20 is normal. You can still have decent vaccum and have a bad head gasket. The rings on the head gasket around the cylinders help that out.

[SappySE107]

14 is fine. I dunno what spec is but its 16 for a 3100.

[ryan.hess]

Theres lines that run into the throttle body from underneath. Suspect those, especially if you have removed the plenum recently.

Yeah, they were a little drippy after I took it off, so I replaced everything, and while it's steaming, it's bone dry, so I know it's not that nor the plenum o-ring.

Otherwise theres the line going into the firewall by the brake booster, it leads to the heater core.

I just found that (thought it went into the passenger compartment at first, but then saw the metal line). It *appears* to be bone dry as well... I pulled up the reflective fabric on the heater core lines, and checked those... Right now, that's my guess as to what's causing the problem - BUT, they're completely dry. The rubber looks a little worn, but it's dry.

Then theres a metal line that runs from the water pump down the passenger side, you could just follow that, it tends to rust and leak, but I cant see where it would leak onto anything hot enough from there to boil off and make steam.

Is this one of the hoses/pipes that leads into the heater core? God, this thing has be stumped... The steam/smoke seems to be coming from around where the crossover connects to something or other near the firewall. I'm gonna go start it up again to see if I can locate a source. This thing is gonna be the death of me..

[ryan.hess]

The steam seems to be hugging the tranny dipstick. I can only see down to the exhaust crossover, so it may be coming from below that.. I think I can almost rule out the area around the heater core, as they're still dry (as near as I can tell without burning myself). Are there any other hoses around the tranny dipstick area!?!

[ryan.hess]

Is there another hose I can't see?

[grandprixgtp_91]

there is a spot where both my gtps was leaking coolant from, it is where the line that plugs in right next to the thermostat goes. it is on a quick connect and they break very easy and leak alot all over your exhaust crossover pipe giving you lots of stinky white smoke. it is almost impossible to see it leak though. i replaced both of them on my cars and it was only $20 for a newer better coupler and quick connects and o-rings for the pipe. i got it all at the dealership. also check to make sure that the line is bolted to the plenum and bolted on straight, this can also make it leak.

[SappySE107]

You can get that part from advance for 9 bucks, if that is what the leak is.

[jmgtp]

ah yes I remember dealing with that stupid fitting. Well on my car the fitting never broke but the o-ring inside crapped out. I just popped a new o-ring in (actually ended up double o-ringing it cause the new single one still leaked) that fixed the problem. The 96 manifolds use a different coolant line instead of that pos snap in piece so I dont have that anymore.

[ryan.hess]

Just an update... I believe I fixed the problem. Turns out there was some "fabric" type stuff where the exhaust bend is near the firewall... It was soaked with coolant from changing the intake before, and it appears to have been draping over the exhaust, therefore steaming/smoking when it got warm enough. I tore off the offending sections, and it hasn't done it since. [knock on wood]

[93GTP]

I had a similar problem, only the sound absorber on my car was soaked with power steering fluid from when my high pressure line popped.

Damn power steering fluid stinks so bad when burning, almost as bad as brake fluid.