Smoky 944 Turbo

[sulzeruk]

Hi all, I have recently bought a 1986 Turbo, there are various small problems on it, the worst being that on a trailing throttle, when I am coasting along in 4th or 5th at about 2000 RPM, if I lift off the throttle and then put my foot down again, I am getting a puff out the back. This is usually a sign of stem seals being knackered, anybody confirm this for me. I managed to scrape an MOT after getting the CO down to 3.4 percent, tried to lean it off a bit more but the mixture screw on the throttle body is at its tightest setting, any ideas, it is also going through the juice at the rate of about 20 MPG even on a run? Any suggestions?
One last one, the last owner sealed up the sun roof, how would I get it out to install new seals, where is the motor for it?
Al Cowan

 

[Indi9xx]

The mixture problem could well be a faulty fuel pressure regulator. They often fail causing either raw fuel to pass the diaphragm into the vacuum pipes (and on to the intake) or they stick causing high fuel pressure.

The airflow meters are also getting to a point where they all need a refurb.

Last of all, the throttle position switch could be faulty.

With the smoke, its probably worn valve guides, worn valve stems or bad stem seals... or all 3 or any combination of the 3.

If its a red 86 turbo, possibly still with BBS cross spoked split rim wheels (gold centre, polished rim), and a badly fitting front bumper, get in touch, I have some bad news for you. (

 

[John Maddox]

I agree the fuel regulator may be the culprit. Cheap to replace so rule it out before going further.

 

[sulzeruk]

No, it is a black one with black leather interior, highish mileage at 139,000. An excellent drivers car I must add. Will order up a fuel pressure regulator and see if this makes a difference. I intend to do a full engine rebuild over the winter anyway as the front pulley seal is leaking oil slightly.
The idle on the car can be a bit erratic as well, it sits just above 1000 rpm sometimes?!?!?!
Al Cowan

 

[Indi9xx]

Hi again.

I have just re read your original post....

The screw on the throttle body is the idle speed screw, not a mixture screw... so if you have wound it all the way in, it will have to low an idle bypass setting, the the idle control valve will be bringing up the revs itself.... you need to set up the idle speed using a jumper wire to stop the ISV working, which will then allow you to use the screw to set the idle speed. If you want I can give you some detailed directions.

The mixture screw on a 944 turbo is in the airflow meter... you will see a hole in the airflow meter next to the intercooler hard pipe which runs over it.. you need to use an allan key to adjust it.. for a non cat car, I normally recommend its set between 1.0% and 2.5% depending on some other factors.

I am sure glad your one isnt the red one I know of.

Its a red 944 turbo 1986... its had two serious front end accidents, which you can see by looking down into the engine bay, where the chassis rails look like they have been attacked with sledge hammers... the car used to be brought to me by a customer who used to refuse to maintain it, just pay to have things that fall off re-attatched... Anyway, it suffered a head gasket failure, we took the head off and the bores had serious scores and gouges from the turbo which had also failed... we advised the customer and he told us just to change the gasket and fit an old turbo he found on ebay.... As a result, it was still a smoker when the work was done, and he promptly sold it to a dealer... who when I last looked, had it up for sale for £5000 and he wanted an extra bit for the number plate SBZ944 or SCZ944 I think... it also had some blue 968 mirrors which looked odd on a red car!

So everyone... beware.. a rough looking car is often just as bad as it looks... Or worse!