AM993

Hmm, I am not an expert but had the same problem with my car after my shop did the suspension upgrade back in August. They had to unplug the temp sensor on the left side of the engine compartment to access the top of the rear left suspensionwithout damaging the wiring harness. I looked carefully at the connector and figured out that it was not the correct connector (looked slightly different from before, it was missing the rubber/weather protection). I went fishing underneath the heater blower and found the correct connector hanging (not connected anywhere). I took the car back to the shop and after a few minutes the tech advised that they had incorrectly replugged the temperature sensor (wrong plug) and that the "incorrect" was not applicable to my car (meaning would stay unplugged). The tech explained that the wiring harness for the 993 is a standard product and therefore will fit any 993, with any option and for any market, meaning that there are a bunch of connectors that are not plugged). After plugging the correct connector, no more problem. Is it possible that you replugged the wrong connector?

tonytrini

I had the same issue when I did my suspension. The connector was loose and the fan would run for extra 20 mins or so before cutting off. It resumed normal operation when it was correctly seated.

MarkD

Very intersting to hear others have had the same issue.

I am certain there is no other plug available. I am very intimate with the rear of that car now... I think my wife is jealous
All of the connections I had were unique.

Bill (BG993), that is really interesting. The harness work was done on mine years ago also but I did not have an "extra" plug. I noticed 2 wires that are cut in the harness on the left, which is where the harness upgrade is done IIRC. Looks like someone helped me out there and removed all doubt.
AM993 sounds like the same thing with the second plug.

In any case, the problem appears to have resolved itself (those kind of "fixes" worry me) for now so we will see.

Thanks for the extra info!

c993k

I had problems right after I got my Engine Harness Update done at the dealer Champion.
My fan acted the same as yours, I unplugged it and tried it again and it was fine.
Howerver my temp showed very high and the oil pressure very low after 5 minutes of driving, it also killed the battery.
The readings were not real "Thank God!" This was the third after day after I bought the car.
Took it back to find out that the voltage reg/Alt were dead and caused the temp/press readings to change!. They weren't dead when I drove the car to them!
I think the "Engine Harness Update!" or the installers have caused more problems than any other change to many 993's.
I'm glad you got it back to normal. Chris

MarkD

Well, now that I got it out for a drive, the cooling fan problem is back.

Any new ideas appreciated.

Recap:
Fan runs 20 minutes, shuts off
Car is not hot
Engine was out for clutch job, etc.
Temp sensor tests OK based on Jason Andreas' specs. previously posted
Harness recall was done years ago
There is only one plug for the temp sensor available in the harness
All HVAC controls operate normally. Front fans runs, A/C works, etc.

Wierd.

Mike J

I seem to remember if you don't plug in all the connectors to the heating system on the engine (i.e. the fan power, temp sensors, flapper valve activators, etc.) the fan will run even if the engine is cole and in fact run without the ignition on. I encountered this when I reinstalled my engine after a rebuild and, becaues I wanted to check on some stuff, did not fully install the heating system. I eventually had to unplug the fan to get it to turn off.......

Check all the connectors (ie. bent or dirty pins, pinched wires, wire breakage near the connectors, etc.).

Cheers,

Mike

MarkD

Thanks Mike. I think that is where I am headed at this point. Other stuff to do right now but when it's time I guess I will start taking stuff off and looking for physical problems.
I know everything is plugged in but maybe I have a wire issue. That would be odd but I guess there isn't anything else left.

Mike J

Now that I think about it some more I remember I left the fan plugged in but the ductwork was out which means the temp resistor was not plugged in nor the activator on the vacuum solinoid. That keep the fan running. I never looked at the wiring diagrams to figure out why, maybe by not having the temp resistor plugged in the computer thinks the engine is hot, hot, hot and needs a fan cooldown....just guessing though..

Cheers,

Mike

MarkD

Found the problem. Didn't take long once I started looking.

Mike, your post above was very close to my problem.

Just about every plug back there is unique or at least there are no identical plugs near each other... except two. The plug that goes to the vacuum solenoid and the temp sensor. They are the same and I had them swapped. They both reach each other's mate but they are more comfortable (wire routing) in the right place. Figured it would be something simple and somewhat embarrassing. All in all, if this was my biggest problem dropping the engine/trans, I am happy

Thanks for all of the tips and advice. If anything, I learned more about these cars. Hopefully someone else will also benefit from this.

Fini!

Mike J

Its always great with its simple! Good news!!

Cheers,

Mike

chris walrod

Excellent! Glad to hear this!