2001 S60 Stalls at Idle

linuxrunner · Post by **linuxrunner** » 28 Oct 2013, 18:59

my car has started hunting RPM's at idle and acts like it wants to stall. ONLY while warming up though. runs fine when first started (completely cold) and fine when fully warm it only acts up when it's in between cold and warm.

I foolishly assumed based on many posts i read that this was the ETM so i ordered a Sacer contactless TPS without doing any testing. installed it and the problem has not changed at all. (when i pulled the old sensor the film was still in great shape no grooving like i saw on other bad units.)

I have cleaned the snot out of the MAF sensor, but i REALLY want to figure out how to test this unit before i go buying more parts. I looks like it sends an analog voltage so i feel like i should be able to get a multimeter in there and watch it while warming up?

Am i missing something?

No codes even after it stalled during 2 consecutive trips.

linuxrunner · Post by **linuxrunner** » 29 Oct 2013, 18:23

found some instructions on how to test the bosch MAF sensor, mine is the denso unit but it seemed similar.

Test numbers were totally different then what was expected for the bosch device (not sure what the denso should be)

Went to an autoparts store and picked up a new Denso MAF sensor installed it figuring that if it does not fix it i'll return it and say it was the wrong part

fired it up and still jumping around at idle (and if i hold VERY lightly on the accelerator it will rev up and down like it has a mind of it's own.)

Unplugged the battery to reset the ECU now i have to wait until it cools off again to test it again.

Does not look promising.

Post by **regent** » 01 Nov 2013, 09:28

Have you checked the ECT sensor?

Post by **precopster** » 01 Nov 2013, 14:48

Just because a Sacer sensor is fitted it doesn't necessarily count this out. 40% of ETM failure is the film problem. Other issues are enlarged (corroded) magnets, board problems and foreign fluid entry.

+1 on the ECT Someone recently posted a range of resistance values to expect without unnecessarily tossing this out in place of a new one.

Post by **mikealder** » 02 Nov 2013, 04:11

Did you mean this graph Mike, shame I can't find the other one I did which is zoomed in around the fan speed switching temps, guess I will have to do that one again - Mike

Post by **regent** » 02 Nov 2013, 16:53

Also, I would inspect the harness for cleanliness, contamination could get the comp confused.