Fabrik8

Wow, sounds like fun. Make sure the cooling system is bled properly.

HighPSI TSi Guy

leak, clogged radiator, bad rad cap, bad fan switch, bad connector. could be plenty of things. If it's boiling at 212 ("normal" temp) then you either have a bad cap or a leak. Sounds like a combination of those problems.

widebody91hatch

well we are thinking it's either the thermostate or the thermo sensor... but that's not the big issue now we've noticed that there is oil going into the intake most likely from the turbo so i got to get that fixed first... so alot of work yet but it's be worth it....

HighPSI TSi Guy

I've never had a thermostat fail in that direction. Ever failed thermo I've ever seen was stuck open. The fan is controlled by a fan switch sensor in the bottom of the radiator. I'd be trying to fix overheating before a leaking turbo. Get a 300zx rad cap on there and fix any coolant leaks. Might as well do a new thermo I guess, they are cheap. make sure the connector is making good connection. Never seen the fan switch go bad but certainly possible.

91cb7

idk what's up with this thing.. it's not over heating now.. it has all the timing done as well as a new water pump. I changed the valve cover and it sounded worse. my brother took off the pipe from the by pass valve and it made it idle better but smoked bad and fell on it's face. That pipe has oil coming out of it badly when he took it off. I changed the pcv valve and and reconnected the piping it's idleing better but still stumbles when about 2k till about 3300 as well as smokes but only on boost. Now what i'm thinking might be wrong is that there is oil where it shouldn't be, and it suffacating the system. I know that it's had one maybe two turbos go on it and that the oil might be from one of them... ... And should there be a hose running from the left side of the valve cover to the air box pipe..

HighPSI TSi Guy

oil will not only foul the plugs but it lowers octane as well. In stock config yes a hose comes off the pass side of the vc to the intake. You don't need it as long as the intake tube hole is plugged. sounds like you have boost leaks or a blown turbo or a combination of the two, among possible other problems. Also check your base ignition timing and verfiy that is correct (properly adjusted CAS).

91cb7

the oil isn't as bad as i thought it was... and the stumbling throught the rpms is something else compleatly now... Simply cause i have no spark now and i'm getting nothing from the coil... is there a fuse or something that controls the coil...

HighPSI TSi Guy

MPI fuse controls both fuel and spark. The spark outputs directly to the ignitor which directly energizes the coil. If you have a lack of spark it is either coil or ignitor. Have you hooked up a datalogger to the car yet?

Join www.sovadsm.com if you have not already

91cb7

no not yet haven't brought it up to a shop... but i'm going to replace the coil first and see it that helps

rhoades

its been a long time since i delt with dsm's, but if I remember correctly from the "cavcar" days Dave is a dsm guru, maybe he can back me up. Have you pulled your ecu and looked to see if the caps have started to swell and pop?