hosrom_951

Something is wrong, i cleaned out my external cooler (not completely but good enough) and now the car runs like a champ. It is 100F tonite (yes that hot here) drive it hard, temp reads either second mark, or just above that. But ONCE the a/c is switched on, the temp rises and stays between second and third, slowly climbing. When i come to a stop, it drops to just over second mark.

Question: The a/c gas is not empty or low, no bubbles showing at the drier. Last Friday, i replaced the a/c blower relay with a used one from my 88 944 NA. Are there a difference in parts? Even THAT day when i changed the relay, the car has been acting funny.

QUestion #2: How would one know if the fuel dampener (on the opposite side of the fuel rail where the Fuel Pressure regulator is located) has failed? I read that it dilutes with the oil causing low oil pressure. Is this true?

I triple checked the vacuum lines and made sure that everything should be the way it is, here is the diagram i followed. Note, the rear banjo where the FPR, Fuel dampener and Fuel Vapor system meet has a 4-way connector,circled in red, is the right?

phlip

You need to check the operation off your cooling fans. With the engine at full operating temp the fans come on at a certain temp, i'm not axactly sure what temp. Then turn on your a/c. When a certain pressure is attained in the high pressure side of the a/c system the green pressure switch near the drier bottle closes, the fans should come on high speed. It's easy to hear the difference between high and low speed. If you dont get high speed I'd suspect the fan relay. Hope this helps

hosrom_951

The fans work the way they should. Between you and me, i checked the vacuum system once more, one mistake. Fixed it, hope that helps the temp because at this one time, i mixed up the vacuum system, car ran hot, oil pressure was ALWAYS under 2 bar. Fixed it, and everything was fine. But for some reason, i re-adjusted a few vacuum lines (for stupid reasons) and all this happen. But i fixed it now, and i shall check that green switch located on the drier.

Darius Juca

Hosrom....simple way to check the fuel dampener....get a fresh oil change....drive the car(after propper warmup of course)...for about 10 minutes and make sure you get on it...check dipstick level amnd smear oil between your fingers and SMELL your oil on your fingers....if the oil has a unburned gasoline smell that is fairly strong then your dampener is going out.

hosrom_951

Guess what, it turns out the the fuel dampner was plugged in the wrong vacuum. Drove it on my way home from work (115F) a/c on and cruising, temperature never got over 2nd white mark, went up just over that in slow trafiic, then fans kicked in. I never knew that vacuum problems would be such a hassle on the colling system!