Jeff PE

The rear spoiler on my 1990 Carrera 4 suddenly stopped deploying correctly. At 45 mph, the spoiler deploys as it should. It does not retract when I stop. I can cause it to retract with the switch on the console, but when I again reach 45 mph, the process starts over again. I get a dashboard warning when I stop, which cancels when I use the console switch to manually retract the spoiler. Car has 49K miles. Anyone have any ideas?

nine64

Jeff,

Post this on 964 board, i am sure some one will be able to help.

springer3

I would start with a search in the 964 archives. The spoiler is pretty reliable, but there are a number of threads where people describe their problems and solutions.

I understand the 92 and up system very well, but your car has different controls. Since the wing deploys both up and down, mechanically you are fine. You have a problem at the controller, wiring, or possibly the extend limit switch. The best advise I can give is to get the wiring diagram for your system, and check the connections and the limit switches. If all that checks out, the control module has failed.

In your car, the control module is located under the passenger seat. If you have the wiring diagram, you can check the limit switches and most of the wiring from the controller plug. The control module is expensive ($245 for a 92 MY), so check the cheap/easy stuff first. The chassis wiring diagram is in the factory manual, but you can't get internal schematics for the controller. I found a bad switching transistor that drives the retract relay. It was an easy board-level repair, and that saved the $245 expense.

Good luck.

mojorizing

Hi Jeff,
here is a schematic of your spoiler wiring


As Springer3 says, look at all the exterior items (limits,connections,etc.), they're the usual source for problems. A little cleaning and checking goes a long way for these old cars of ours. I suspect you might have more than a stuck/dirty limit switch just from your description of your problem.....

In any case, if you read this post from WMRiceman:

post

He kindly set me his failed controller unit and last night I was able to check it out. As Springer3 found, I found a shorted switching transistor that activates the retract relay. I replaced it with a NPN general purpose 2N3904 transistor. I also found a dirty/burned contact on that relay, which I cleaned up. It seems to work on my bench as it should.

It's no use to me because I have a '91 and that takes part # 964 618 212 00 and this is 911 618 112 00 for -90 cars. If after exhaustive troubleshooting you find you could use it and you're in the States, let me know and I'll send it to you.

later, Kevin

garrett376

As seen in Kevin's diagram, I'll bet your "MICROSWITCH REAR SPOILER EXTENDED" is not working correctly. Clean/adjust/replace it as that is likely your problem. Or, switch the microswitch for the retracted microswitch, and likely your problem will reverse- this way you don't have to buy anything to troubleshoot - use the parts you already have!

Jeff PE

Gentlemen, thanks. I was traveling, but when I returned I checked all the connectors and the limit switches. There were no obvious problems, but it must have been one or the other as the spoiler is now working. Now if I can find that pesky oil leak (showing up just ahead of the right rear wheel). The return tubes have been replaced as well as a few o-rings, but the leak remains.

Jeff

HSB

Check your power steering pump and or the camshaft oil seal. Both drip out in and about the same location. If it's the power steering pump it should be hydraulic fluid. I just replaced mine.

dkeen

How difficult is this seal to replace? I just bought a 1993 964 which has a very slow leak here. The mechanic who checked out the car said it was a 3-4 hour job. I would like to do it myself if it is not too difficult.

garrett376

I will sadly admit that I went to replace those two little bastards, and gave up. I found that I HAD to have the pulley holder tool, as I could not get off the dang bolt on the end of the camshaft. I even tried to lock the engine with the tranny, but it didn't work - that bolt is REALLY on there.

Getting there is pretty tough, too - you can see how the oil line crosses over where you're trying to reach - make sure you've got lots of various extensions.

garrett376

Here are the two pieces you'll need if you can get past the pulley:

garrett376

My oil drip is SUPER SUPER slow - doesn't even make a drip, but it's a little wet in the area so I tried to go after it. Since it was not required, I gave up pretty easily. I do recommend you get a pulley holder. I couldn't lock the cam...

Jeff PE

First, thanks to all for help.

Before I return to rear spoiler problem, the oil leak turned out to be one or more of the three hoses connected to the bottom of the oil tank. All three were replaced (parts were about $110, with clamps) and, voila', the drip disappeared.

Now for the spoiler: I replaced the set of limit switches, checked the fuse and connections, and still no spoiler action. It will not actuate from the console switch or when driving.

Is there some sort of reset I must do? If not, is the next likely culprit the motor (which I haven't tested as yet) or the "brain", given that the spoiler does not actuate either way?

Again, thanks.

540964

My spoiler quit after my mechanic had been unplugging and replugging everything in an attempt to find the probelm causing the Christmas Tree Effect. (another long story but I think the car is cured of that now). Anyway, I troubleshot the problem down to the control unit under the passenger seat. Removed the control unit from the car, took the cover off and found that the solder joints that connect the circuit board to the connector were cracked, probabl from unplugging and replugging the connector. I took a soldering iron and re-flowed these joints - the spoiler has worked fine ever since.

Jeff PE

Kevin, if you still have the control unit for the earlier car, I would be interested in it. I am in Northeastern US. Thank you. Jeff

mojorizing

Hi Jeff,
Email your shipping address to me at my911targa@***.net and I'll send it to you. If it works out for you, please send me your failed unit and I'll check it out.
later, Kevin