rsabeebe

a busy schedule and cold(ish) weather here in Dallas has limited my time to look into the cause of my coolant 'leak'. i took these pics this morning because the exhaust looked a bit thick. i know it's hard to tell from a pic, but thought i'd post and see. anyone care to comment if this looks a bit too 'steamy' for a normal start up? temps were probably in the mid 40s and i just thought it looked a bit on the opaque/steamy side.

RT930turbo

Looks pretty normal for a 40* Cold start. Did it dissipate when it was warmed up? Any loss of coolant?

RT930turbo

Nevermind... Saw you mentioned a coolant "leak" in your post. I still don't think the moisture on that cold start is excessive, but if it stays heavy when hot, and you're loosing coolant, I'd investigate further.

mytrplseven

Sounds suspiciously like a head gasket issue.

Ni944S2

if you suspect a hg leak of coolant into a cylinder, check your spark plugs. It will be very obvious, the plug will be "steam cleaned" and look new - noticeably different from the others.

plumbum

Key is what does it smell like? If it smells sweet..it is coolant...also checking the plugs should let you know if you are burning coolant

bordin34

Read through this thread. It is what I did when I thought my head gasket was failing last year. Turns out it was bad.
http://dorkiphus.net/porsche/showthread.php?t=29499

rsabeebe

@bordin, i did read through that thread already and it was quite informative. still waiting to have the time to source my leak/disappearance.

the strange thing that leads me more towards a HG leak than normal is that i lose coolant after the car has been run and shut down. i believe it comes from the overflow which would indicate built pressure pushing the coolant out. aside from that, i would be considering rad leak or water pump (early design, assuming it's original) leak - which is common on early 951s. i have all new coolant hoses from LR and plan to install those this weekend and will inspect my thermostat (and overall WP area for leaks), but if all that checks out, i'm back to thinking HG. going against the HG theory is that the exhaust does not smell sweet and i did just change all the plugs and all looked the same - a nice dry-ish brown color. no particular plug looked 'steam cleaned'.

trying to source a rough idle issue, i also changed all plugs, dist. cap and rotor. the car runs much smoother now (still a rough idle - motor mounts to be changed in weeks) and i lost the stumble i had @ 5k rpms. the car now runs nice and smooth to 6k.

i also have all new vacuum lines and intercooler hard pipe hoses to install. going to check j-pipe for cracks and all connections @ the j-pipe for potential leaks. j-pipe looks to be in great condition, but will still inspect. changing to MAF soon, but maybe not for a couple months.

kev951

rough idle could be coolant fouling out plugs. pressure test car when cold, pull spark plugs, look for leaks. same test with warm engine. does your heater work ok?

rsabeebe

heater works great when coolant is refilled. when it gets low, heat diminishes - as expected.

odonnell

plumbum

He is way to positive about blown head gaskets lol

KevinGross

The "block check" tester in Michael's video post is the way to check for head gasket leaks. Inexpensive and available from any auto parts store.

Kevin
Catellus Engineering

bordin34

Mine tested negative with the block tester yet still had a bad head gasket.

odonnell

Haha I agree. His videos are kind of tacky, but some of them have good content. I'd be lying if I said I haven't learned quite a few useful tricks from him.