240 - 1992 - Idling fast when engine warm

Rob1 · Post by **Rob1** » 17 Dec 2009, 10:42

138k original miles.

It seems to idle fast when the engine is warm (only in park when you are ready to shut it off) but if you shut the engine off and restart it seems like it "resets" back to the proper idle.

Ran the on-board diagnostic:
*with the wire is the 2nd hole - it flashed the following codes 3-1-1
(speedometer signal) and 2-3-2. Went through the process 3
times and got the same codes with the exception of the 2-3-2
(Lamda adjustment)which I only got on the first time around.
*with wire in the 6th hole - code 1-1-1. ( no faults ).

Any suggestions would be helpful. Thanks!
Just curious??? What are the holes 1,3,5 on the OBD used for?

Take Care!
Rob

Post by **billofdurham** » 17 Dec 2009, 11:49

3-1-1 Did you run the test as detailed in the 'Fault Code Testing' section of the instructions?

2-3-2 May have been triggered by the higher idle speed which could have caused a richer mixture. Is the higher idle speed still occurring?

My usual approach to fixing codes is to read them, erase them and run the car to see if they set again. A lot of times they don't as they have been the work of those notorious Volvo gremlins, whose sole purpose in life is to make you worry that you have broken your car.

The OBD box was ahead of its time. On the 200/700 sockets 2 and 6 were connected but the others were not used. Cruise control can be tested using the OBD box but it has to be linked to the cruise unit with an extra lead. The power seats can also be tested with an extra lead.
On later models two boxes, A & B, were used giving access to more diagnostic testing. Again, not all sockets are used.

I think Volvo were going to expand the uses of the diagnostic system but OBD11 became the industry standard and from 1996 models you need a code reader.

Bill.

Rob1 · Post by **Rob1** » 17 Dec 2009, 12:41

Bill:

Thanks for the response.

Yes, fairly certain I followed the directions.

That is a good idea to erase the codes and drive the car and reread the codes.
I will erase the codes today and then read them on Saturday. Then will post the codes late on Saturday or Sunday.

Thanks for your help and Take Care!
Rob

Post by **billofdurham** » 17 Dec 2009, 12:59

Yes, fairly certain I followed the directions.

I wonder if you misunderstood my query.

I wasn't doubting that you followed the directions on using the OBD but for certain codes, marked (2), there is another section immediately after the code list that gives instructions on how to test the unit the code relates to.

However, I still stick by my erase it and see what happens policy.

Bill.

Rob1 · Post by **Rob1** » 17 Dec 2009, 13:12

Bill:

No, I did not test the unit the codes referred.

Take Care!
Rob

Rob1 · Post by **Rob1** » 22 Dec 2009, 14:27

I apologize for not getting back when promised by Sunday.

I have been trying to duplicate the fast idle to no avail.

Have reset & read the codes. It shows a 1-1-1 or a no fault which matches.

Guess I will wait until the problem shows up again and reread the codes a couple of times and then get back on.

Appreciate the help. I have a plan to follow when it happens again.

Take Care!
Rob

Post by **billofdurham** » 22 Dec 2009, 15:15

Guess I will wait until the problem shows up again

Hopefully that will never happen.

Bill.