An 04 Evo RS wanted to compete in a big race this past weekend so he made his tuning appointment in advance a few weeks out. Upon his arrival to the facility we noticed coolant and oil leaks galore and were very hesitant to allow the car on the dyno as those messes are hell to clean up. For any other local customer we would have politely declined but since they drove in 4 hours or so from out of state we went ahead and suited up the Evo with our wideband and monitoring equipment so we may be able to closely watch the engine vitals while testing and tuning the car.

After calibrating the roller speed of the dyno so that the dyno understands how fast the car is traveling at 4000rpms so it can automatically start and stop recording of data within the given rpm ranges we looked at our datalogger and it was showing coolant temps already in the 235*F range which was into the high range for the temps. Keep in mind this was without boost.

So at this point a bad headgasket was already suspect, it has already been determined that the engine was leaking oil like a sieve and it was just a matter of time before our suspicions were validated. A baseline pull or two later, with both fans working properly, the coolant overflow was pissing out so that was our confirmation. The cylinder pressure was leaking through the headgasket into the coolant passages, increasing pressure and heat and pushing it out of the reservoir. Unfortunately outside of swapping the HG which is a half a day job, the tuning would have to be postponed.

The moral of the story is: Don't rush things when it comes to such vital parts of the car. The heart of the car is the engine. If you do not have the proper bolts for the turbo return line, then wait for them to come in. If you do not have the gasket for here or there, then get it. If your engine is leaking oil, then don't drive it until its fixed. If your coolant temp needle is rising, then get your Evo looked at. If you don't want to spend the time to seal a leak, then have a pro do it for you. If your car is misfiring or has old spark plugs, then change them. You will only thank yourself later when the car runs as it should on dynotuning day.

 

nICE... what was the outcome of the car?

 

....it always amazed me when such things like you descibe are occuring from the engine why people insist to get dyno/tuned... has a good risk to lead to catastrophic outcomes.

 

its because alot of newbies assume the tuner will also magically fix his car for free with a snap of a finger

 

A friend of mine wrote this a while back.......he got tired of dealing exactly with what you guys posted....(it speaks specifically for 300ZX's, however, alot of it can be generalized)

http://www.twinturbo.net/net/viewmsg...cal&dtSearch=1

 

A lot of newbies are unware of existing physical and mechanical issues, and think problems can be 'tuned out'. This is severely flawed reasoning, and leads to loads of frustration and expense, later if not sooner.

I won't touch the tune without having a careful look over things myself, and asking pointed questions about the car. If it's not in clean running order and free of pressure leaks, the worst thing one can do is seek more power out of it.

 

Thats true TED B , sometimes the car has all the correct parts on it but people overlook at whats needed to make the most out of they have ... assuming is your worst enemy when it comes to making high power

 

Nice parts need a nice install too. A lot of people automatically blame the tuner when their car doesn't belch out the power they want.

Fortunately we drive nice, fairly new cars with a good baseline set in. Most race car tuners won't even touch a car that was not built by them because of this problem.

 

That looks like a ga evo, guess he doesnt trust any shops in ga to look at it