Over 60, the 4wheel drive light came on.

[Hawktel]

So in my 89 C4, I was out on the free way for the first time and the ! light came on, and then the 4 wheel drive idiot light over the oil level came on.

It has done this every time I have it over 60 for more than a minute or two.

When I stopped and did a visual I see nothing happening, no heat issues no unusual noise. No problems I can find and it goes out, until again I get up to 60 and withing a few minutes it comes back on.

A guy I spoke to told me this is common for C4's.

Can I ignore it? What should I be doing?

[budge96]

Well if I were you I don't beleive I'd ignore it and whoever told you this is common for C4's is
an idiot and that should be your last question to him!
First thing if you have a manual check there for cues as to running problems and faults with
the four wheel drive mechanism on your car.
The early C4's had a complex clutch mechanism style coupling that sends a small modicum of
torque to the front differential unlike the later C4's that use q viscous or liquid torquing
mechanism.
My 993TT has a small reservoir for a vegetable oil fluid that needs topping only once every
two or three years if that..I don't beleive the earlier C4's have that reservoir but it might not hurt to check?
The idiot light must be indicating loss of torque on one or the other end so maybe the clutches in the transfer tube are in need of service.
With that car I would certainly consult a professional that knows what hes doing and can be trusted ..let us know what you come up with, thanks and good luck Bert

[Hawktel]

Ugh I was really hoping more would chime in! Thank you very much for the response though Bert.

On your ride does the light come on when you don't have the reservoir topped up?

[budge96]

Uhm ..no I don't recall ever seeing that symbol or if the torque "4-wheel" symbol exists in the same manner on a turbo.
I believe they're different designs entirely,I could make a call to a tech that I know see if he has any pointers for you ..Bert

[budge96]

Hawktel, i spoke breifly with a bud thats a factory trained porsche tech at the dealer ,he
suggested having the transmission examined by someone knowledgable, (ie auth service center) reason being the front differential is not receiving specified torque from transaxle and
torque tube (light warns of slippage),indicative of warn clutches in transfer portion of trans.
You could luck out and discover front pumpkin needs service but doubt it.
Good luck and post what you find out..thanks Bert

[Hawktel]

Ugh. Not good not good at all. Not what I wanted to hear on a car I have driven for a week and a 1/2. It didn't do this when I bought it!

Well, you don't win them all.

[budge96]

I don't know where you bought it,private owner or business but 10 days is unreasonable to have a catastrophic failure..
You need to contact them immediately and inform them as such to refund cost of repairs
(they had to know about it) or your money back!

[Hawktel]

I spoke to them on it, they are aware of the issue now, but he did quote me the as is guarentee..

I really like the car, and I am going to see if I can fix this. Here is what the owner's Manual for a 89 says about this idiot light.

Longitudinal and Transverse Interlock Warning Light. Red.

This Warning light indicated a malfunction or failure of the interlocks. If this occurs, you must adjust your driving to the resulting changes in your Porsche's handling characteristics.

So I guess I'll start a new post on the Interlocks and see what people can tell me.

Consult the nearest authorized PORSCHE dealer to have the Malfunction corrected.

[911Urge]

If the warning light comes as you described its throwing an error code. Have a pcar shop see what the code is along with a visual inspection and start there.

[Hawktel]

What does it take to pull the codes on the 964s? To much to hope for some turn the key on and off action?

[Garrett]

It is actually a common problem with C4's. Your longitudinal accelerometer needs to be cleaned.

Search RennList for the specifics...

[colo964]

What Garret says is true. Mine did what you described for the first year. After that I grew a pair and started messing around with sensors etc. I suggest you do the same. The accelerometers are under a hatch that is on the right side below the shifter. Really it's easier to pull the console.

One of them sits sideways and the other long ways. I forgot which turns which light on (1 does the 4WD and the other works the ABS and 4WD, if I recall). You can unplug one at a time - the one that sparks the 4WD light only (as soon as you turn the car on) is the one you need to crack open and blow out dust and recent the little arm. Those are pricey to replace,but relatively simple devices. Get the Bosch book on ABS system for some good background on them. Good luck.

[Hawktel]

Hey guys thats a great help. I'll get on Renlist and get working this out.