Sudden erratic idle, and consistent stalling within seconds

SpaceCadetSD · Post by **SpaceCadetSD** » 28 Sep 2010, 20:44

I've noticed that many in this room have stated that problems with their ETM accumulated slowly, and only occasionally caused stalling. I have a '00 C70 LPT convertible, which I've never had any stalling/throttle issues with in the past. But, true to Murphy's Law, when I left CA last week bound for GA my car died near El Paso. I had accerated to pass a truck, then the engine basically lost all power--I coasted over to the shoulder. There, when the engine had slowed to idle, it kept slowing and surging (~400RPM up to 2K RPM) then stalled. CEL on. I cleared codes, restarted, same thing engine was erratic stalled, couldn't drive the car more than a few hundred feet at a time (which I could only accomplish by pressing the accelerator up above 2.5K RPM as soon as starting--no surging while idle at higher RPMs, but still not driveable).

My car is still in El Paso, while I'm in GA with a rental. The dealer there still hasn't diagnosed the problem, and is quoting about $2K in repairs. Seems as if they want to just start replacing parts till they get it right.

I've read through several threads and haven't found a real close match to my situation, so I'm just hoping someone has experienced nearly or exactly the same symptoms and can shed some light on this by their own experience.

Thanks!
Brandon

xk150 · Post by **xk150** » 23 Jul 2011, 20:08

Hi,
I am having a smilar provlem with my 2002 HPT C70... but only at start up... The engine runs rough and the rpm's jump from about 800 to about 2500... this lasts for about 4 or 5 seconds then the idle smooths out the the car runs fine... No issues while driving...
Any ideas?

Thanks

SimLyons · Post by **SimLyons** » 23 Jul 2011, 20:26

I had not the exact problem but similar when I failed to reconnect my AMF electrical connector. Before it was connected it would start, run ok, but as soon as I tried to go it died flat, unless I goosed it and did the unthinkable...dropped it into gear.

Also, cleaning the MAF with a $7 spray can of MAF cleaner can make a difference. Front O2 sensor combined with dirty MAF will surely cause these symptoms. Maybe $200 max with labor. (And the O2 sensor can fail fast!)

xk150 · Post by **xk150** » 26 Jul 2011, 19:50

Thanks for your response... What about cleaning the ETM? My ETM does have a yellow sticker..
Other thing, had a vacuum hose disconected... the one that comes off the top of the intake manifold and goes into a Tee fiting... one hose goes to the switch by radiator other goes to the round plastic pipe that comes off the air filter assembly... reconnecting didn't seem to make much differance.
My car has 157K miles on it... runs good except for this new problem at start-up...

Thanks

xk150 · Post by **xk150** » 30 Mar 2012, 21:03

Discovered my problem... it was a defective ETM... Volvo replaced it free of charge... one week before the 10 year extended warrenty expired... what great luck...

Post by **MoVolvos** » 30 Mar 2012, 21:14

xk150 wrote:Discovered my problem... it was a defective ETM... Volvo replaced it free of charge... one week before the 10 year extended warrenty expired... what great luck...

What a HUGE BLESSING in disguise.

Blessings,

BKM
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