Intermittant low idle and slow accelleration

[dunedin]

Can anyone help..
I have just bought a '82 911sc coupe and it runs great when motor first starts out. I can drive it for 10 miles and everything is fine. Stop and start again and it acts up with low idle and slow accelleration and during long hauls. Could the problem be that the distributor advance is sticking? The car was only driven 500 miles in one year, could it be bad gas? Or could it be a simple adjustment of the fuel mixture? Has anyone had this problem?

[82sctarga]

Since my 82sc had that low hunting idle, I disconnected the O2 sensor (Black 1/2" dia plug just ahead of CD unit) I could not believe the difference. You will probably have to adjust your idle speed after this.

[wckrause]

Sounds like mixture, but as a new owner, you should go over the basics.

1. Check ignition timing.
2. New plugs.
3. New cap and rotor. Remember to oil the distributor, under the rotor.
4. Get a shop to set mixture using an exhaust gas analyzer. A lot of SC owners disconnect the O2 sensor (and still pass emissions).


------------------
Bill Krause
'79 911SC Euro
MY PELICAN GALLERY

[john walker's workshop]

what you have most likely, is a intermittent relay problem. if the relay that operates the lambda computer under the passenger seat fails, the car will run exactly as you describe. it gets it's power from the domelight fuse. it sits next to the computer against the tunnel. it's a $5 part, so replace it and find out. the computer needs to work regardless of the oxy sensor being connected or not.

[dunedin]

Originally posted by 82sctarga:
Since my 82sc had that low hunting idle, I disconnected the O2 sensor (Black 1/2" dia plug just ahead of CD unit) I could not believe the difference. You will probably have to adjust your idle speed after this.

I will check to see whether the O2 is connected or not. Previous owner said he had his mechanic make some adjustments for performance.

[dunedin]

Originally posted by wckrause:
Sounds like mixture, but as a new owner, you should go over the basics.

1. Check ignition timing.
2. New plugs.
3. New cap and rotor. Remember to oil the distributor, under the rotor.
4. Get a shop to set mixture using an exhaust gas analyzer. A lot of SC owners disconnect the O2 sensor (and still pass emissions).

Thanks. I've heard that the vacuum advance under the rotor can get sticky, so I'll check that out as one of the first things. I planned on going through the whole car, just wasn't expecting it have a problem the day I took it home. I'll advise.

[dunedin]

Originally posted by john walker's workshop:
what you have most likely, is a intermittent relay problem. if the relay that operates the lambda computer under the passenger seat fails, the car will run exactly as you describe. it gets it's power from the domelight fuse. it sits next to the computer against the tunnel. it's a $5 part, so replace it and find out. the computer needs to work regardless of the oxy sensor being connected or not.

Thanks so, much. The relay sounds like a good bet. I'm going to see if I can get one. By tunnel are do you mean between the seats, or exactly where is the relay?

[lagoon]

It is under the passenger seat next to the computer with a 6 wire connector on it.

Originally posted by dunedin:
Thanks so, much. The relay sounds like a good bet. I'm going to see if I can get one. By tunnel are do you mean between the seats, or exactly where is the relay?

[jason1guy]

would any know the part # of that relay that john walker mentioned in this post.
lambda sensor relay? thanks

Jason
81 SC

[john walker's workshop]

relay #821.951.253. it's a universal relay. lots of uses. this one just has a mounting tab on it.

[dunedin]

Originally posted by john walker's workshop:
relay #821.951.253. it's a universal relay. lots of uses. this one just has a mounting tab on it.

Would you know if there is an aftermarket or Bosch part number? Having problems with parts shops referencing the #821.

[dunedin]

Originally posted by john walker's workshop:
what you have most likely, is a intermittent relay problem. if the relay that operates the lambda computer under the passenger seat fails, the car will run exactly as you describe. it gets it's power from the domelight fuse. it sits next to the computer against the tunnel. it's a $5 part, so replace it and find out. the computer needs to work regardless of the oxy sensor being connected or not.

Able to locate a new relay and it did the trick! The car performed exactly the way it should. What a difference even at the turn of the key. Thanks again, for all the responses from everyone! This site is a great learning post.

[jason1guy]

do tell, where did you get it?
is there another part #

Jason

81 SC

[dunedin]

[QUOTE]Originally posted by jason1guy:
do tell, where did you get it?
is there another part #

Jason

81 SC[/QUOTE
Bosch part #0332-019150 and Echlin cross ref part #AR230 which I got at a local Napa parts store.