Hi Guys



I have just got my 1982 928 back from 18 months in Sydney (400km away).



Hope one of you learned gentlemen can assist?



Its idle is too low. I can find lots of things on too fast, but not too slow.



I understand there is a screw adjustment on the throttle body.



I have a stupid question – where is it?? Can someone up/download a photo showing me the location.



Sorry for the question.

 

Welcome back!
According to my chart you have a K-Jet (CIS) injection car, if in Australia. Please confirm.
If the car ran fine before you parked it, I wouldn't mess with the air/fuel mixture until you rule out some other things.
First, how long have you run it since it's hibernation? Long enough for the fuel system to "clear itself"?
Does it seem to run fine when your are on the throttle and driving around, or is it sluggish?
The reason I ask is a low idle might suggest you are not firing on all cylinders. Double check your spark plug wires, and check your ignition timing.
Make sure you battery is charged and you measure a good 12v at the jump post at rest. And 13v+ when idling.
If it is a fuel issue, some of the CIS guys will have to chime in....that system is above my pay grade.
-Jason

 

Hi Jason89s4



Thank you.



It has been with the mechanic in Sydney for 18months (no one in the bush was capable) and most of the important mechanical jobs “should” have been done.



I thought it was a L-jet. But how do I check. But you are far more knowledge than I, so let’s go with what you said.



I took it for the 400km drive back to the bush on Sunday and when we stopped at the 200km mark it was had to start and at idle it was not charging the battery. This is the first time it has had a long run ever in my ownership (aside from taking it to the mechanic 18months ago).



I also did a short run to the car wash (we have water restrictions and we are not allowed to wash our cars). Took it home and about 1hr later is was hard to start. In a similar manner to the stop on the way home from Sydney.



It has a new battery. The mechanic suggested I adjust the idle that is “somewhere” in the middle of the V.



Driving around it seems fine. But honestly, I bought the car and then immediately took it to the mechanic, so I am not familiar with this car. My last Porsche was a 1971 911 T, so a totally different cup of tea. I drive a Toyota Camry 2005 V6. So, a novice.



But having got very upset with google, I could not find the position of anything that resembled an idle screw.


D

 

There is a large screw (slot) head at an angle in FRONT of the throttle body, front of the spider body - anticlock turn to increase idle.If you have hard steel tubing lines to each injector the car is CIS or K-jet - a mechanical injection system that does NOT do well if left unused for long periods , due to residue left behind by evaporating petrol. If you have this system, DO NOT play with the mixture adjuster behind the spider body! If you can see wire leads connecting to each injector, you should have an L-jet electronic injection system. This link might work for you....
https://www.google.com/url?sa=i&sour...68519710481502
400kms from Sydney is where?
Idle should be 700+/- 50 rpm in neutral
jp 83 Euro S AT 57k CIS

 

In order to help you decide which fuel injection system you have, the first pic is of my '83 with an L-Jet. I don't have a K-Jet car, but the second pic I snapped in a junkyard and is of a Euro with K-Jet. Notice the fuel injectors..the K-jet does not have wires to the injectors. The L-Jet does, and has the fuel pressure damper up front. (The K-Jet is Continuous Injection System-CIS so the fuel distributor sends pressurized fuel directly to each injector in the appropriate rotation, the L-Jet is Electronic Fuel Injection-EFI, so each injector only opens by electronic signal when told to do so by the ECU.)
If yours is K-Jet (CIS) as I previously stated, I would follow jpitman's advice and don't mess with the mixture until you have the fuel pressures correct.
Again, folks from this forum with more CIS knowledge can chime in, or you can search for CIS threads. Process of elimination--check what I mentioned in previous post and report back.
-Jason

 

Jason,
the man says he has an AFM, so I think its at least L-jet. Either way the idle screw is in the same place.
jp 83 Euro S AT 57k

 

Hi Guys

All great answers. But I still have no idea if I have K- or L-jet.

I am in Orange, famous for water restrictions, most expensive council rates in the state, cool climate wines and the Orange Watch Company.

“The man says he has an AFM”…what is an AFM.

I took the car for 45min run in the country. Blistering acceleration, got past the 100km speed limit in no time. But I had myself and my 11 year old, so stuck to 100km. Mostly good, the A/c was not working and I still have to find my radio as the Sony one that came with the car does not work.

I do find the accelerator pedal a little stiff. A good thing, so I do not speed, but is this a feature.

Anyway, I did find the screw and screws it anti-clockwise and basically nothing happened. The car was ticking over at about 400rpm. At least the battery light was not on.

You say 700…so I am low by 300.

D

 

If you have hard steel lines connected to the injectors, you have CIS or K-jet - pic2 above. If it has wires connected to the injectors its an L-jet - early electronic system. Try screwing the adjuster out some more maybe. If its at 400 in neutral, I would expect it to stall when put in Drive. ? If your VIN goes WP0ZZZxxx your car is a Euro (as distinct from a US type model), and is probably CIS. In this case there is a mixture adjuster behind the spider body, but its VERY VERY sensitive, and should NOT be played with until you have the right equipment.
If you are in Orange, join Landsharkoz, and post there - there are some 928 people not too far away.
Any history on the car - why was it with a mechanic? What was he trying to fix?
jp 83 Euro S AT 57k

 

Or, upload a photo of your engine and we'll tell you what you have.

 

Thanks for the replies

I have a WP0ZZZZ 1982.

I bought the car about just over 2 years ago from a guy who was not into cars. He bought it from another guy the purpose of flipping it. It sat in his garage and was unregistered. Knowing the guy was typical aussie into football meat pies and Holden cars,

I told my mechanic to do all the big things than needed…water pump, timing belt, spark plugs etc. I still have the little jobs like: sunroof, radio, A/c, low idle; that hopefully can fix or pray to all the gods that the locals can do something. Last time I tried a local mechanic was with a Volvo 960 Wagon, they said it was “an exotic car” and the shook their heads. Joy of living in the bush.


D