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Aronkovacs
10-23-2014, 11:55 AM
Hi guys,

I am a happy owner of a 2000 V70 XC. 173K miles. Looks good, feels good, Drives goo...., until recently, when after starting up, the idle started fluctuating, and the car stalled after starting up. Giving some gas helps, and it;s driveable as long as you press on the throttle. Slight misfire, with no code. Gone as I step on the throttle.
Recently all spark plugs were replaced, new motor/tranny mounts, new air filter, fuel pump+fuel filter, oil change, all the maintenance stuff. I threw the following codes:
ECM-130A Intake air leakage. Faulty signal
ECM-4801 TCW (30way cat. conv.) efficiency
ECM-262A Long-term fuel trim
ECM-261A Long-term fuel trim.

It also threw a code for MAS, but that had been replaced with one from a 2001 XC70 (Identical part/model number) That's gone.

Air leaks had been checked, but none were found. Turbo hoses tight, now I'm clueless.
JRL
10-23-2014, 01:40 PM
CAT
02 sensors
vacuum leak (until the car is smoked you really do not know if there is a leak or not)

Take your pick
All need to be tested for efficiency
Aronkovacs
10-23-2014, 01:57 PM
CAT
02 sensors
vacuum leak (until the car is smoked you really do not know if there is a leak or not)

Take your pick
All need to be tested for efficiency

Would a clogged/cracked PCV System also show vacuum hose leak? I can't find the breather box on the turbo model.
hoonk
10-24-2014, 06:49 AM
I can't find the breather box on the turbo model.

It's under the intake manifold

6593


And as others have suggested a smoke test is a great way to find air leaks. It is possible your used AMM is better than your original, but still not good.


"New fuel pump" - what is the fuel pressure?
Aronkovacs
10-24-2014, 03:23 PM
OK, So I erased codes, car ran fine, and the idle started moving up and down. Delayed reaction to the throttle, and if I press the brake and gas at the same time, the throttle is not responding. No CEL, no codes
hoonk
10-25-2014, 08:00 AM
idle started moving up and down. Delayed reaction to the throttle, the throttle is not responding.

99-01s are known for bad throttles - since you listed Volvo codes (not generic obd2) I trust you have access to VIDA. That software can test your throttle -
Aronkovacs
11-06-2014, 11:20 AM
OK. So I found a leak source fixed, MAS Replaced, runs good until it rains, then it starts acting up again.