P0101 still chasing.

johnboy77 · Post by **johnboy77** » 07 Jan 2019, 09:49

I’ve been chasing a P0101 since I got car. Had a p0088 which I fixed by replacing PEM. Checked voltage on MAF. 14v from one pin, 5v from another and 1v that rises when I hit throttle. Can’t find any leaks in vacuum hoses. I also did a hard reset by disconnecting the battery and tying pos and Neg together for 10 mins. I’ve also tried to do the fuel trim reset by turning key to pos2 for a min before starting car but I didn’t hear any noises. Sprayed starter fluid all over hoses and no change in rpm. Glove test shows Neg pressure. Car has 120,000 mi. Drives fine although I feel it loses some Acceleraion after warming up. When cold it’s fast. And twice after driving on highway I have come to a red light and it stutters for a sec and feels like it’s running out of gas. But that goes away when I give it gas. If i unplug MAF there is no real change except it’ll start throwing codes. I one time had a P2188 code but haven’t seen it in a week. I have freeze frames from idle and 2000rpm. First pics are from idle.

: Idle

: Idle

: Idle

: Idle

: Idle

Second pic is at 2000rpm

: 2000rpm

: 2000rpm

: 2000rpm

: 2000rpm

Post by **RickHaleParker** » 07 Jan 2019, 16:49

P0101: Possible source
Contact resistance or oxidation in the mass air flow (MAF) connectors
Air leakage in the intake system
Blocked intake system
Damaged mass air flow (MAF) sensor.

1. Clean the connector, MAF cleaner works good.

2. Clean the MAF sensor using MAF cleaner. Anything else might leave a residue that will interfere with the operation of the sensor. Do not to touch the sensor elements. Do not use compressed air on the sensor. The elements are fragile and a slight touch can break them. Just spray the elements with MAF cleaner, let the fluid carry away the contamination.

3. Check for blockage in the Air intake.

4. Replace MAF.

#2 should be done periodically, a clean MAF will increase performance and efficiency.

Post by **ggleavitt** » 07 Jan 2019, 18:15

Car is a 2005 XC90 2.5T AWD

Please put a signature in so folks don't have to wonder. See if this link works, pretty easy to do- ucp.php?i=ucp_profile&mode=signature

In 2005, 3 powerplants and 3 transmissions were offered for the North American market in this car. Gets easier to guess after 2007 but 05-06 is a funny couple of years.

johnboy77 · Post by **johnboy77** » 08 Jan 2019, 00:10

I have cleaned MAF with CRC MAF cleaner. Twice. I’ve checked repeatedly for intake leaks using starter fluid and by hand. The PCV was changed once already in this car and is passes the glove test without issue. I changed the spark plugs yesterday and that gave a ton of pep back and runs great but it still is throwing the MAF code. Not right away but within 20 miles of driving. Do my fuel trims look ok?? Does the MAF volume look off at all? I know P0101 in Volvo means either too much or too little air.

Post by **ggleavitt** » 08 Jan 2019, 12:52

I have one of these on a shelf in my garage, failed and tried to clean it, got around a week before failing again. Was my second replacement (first was "cleaned" by a young dealer tech at my 50k service, lasted about a week as well).

Bunch of write-up's on MAF, here's one- https://forums.swedespeed.com/showthrea ... le-Stutter , I found the cutdown 6-point T-25 security Torx in my toolbox and opened up my MAF to have another look.

My assembly (2005 2.5T) is Bosch PN 0280218088, the MAF inside is Bosch PN F00C2G2064. Seeing just the -064 MAF itself for sale in the event this is the direction you end up going.

Good luck !

johnboy77 · Post by **johnboy77** » 09 Jan 2019, 12:18

The cel came back on today after changing plugs. The usual P0101. I disconnected the MAF harness to see if there was difference and there was none. Does that mean it’s shot.

johnboy77 · Post by **johnboy77** » 11 Jan 2019, 13:41

Installed New Bosch MAF sensor. CEL came back on P0101. Also when I disconnect MAF no change in engine. Glove test sucks glove in. New plugs.

johnboy77 · Post by **johnboy77** » 11 Jan 2019, 13:42

Installed New Bosch MAF sensor. CEL came back on P0101. Also when I disconnect MAF no change in engine. Glove test sucks glove in. New plugs.

Post by **mrbrian200** » 11 Jan 2019, 14:31

At engine temp of 86 degrees C, if those readings on your tool were taken with your foot off the gas with with the trans in 'park' that throttle position reading at 12% is way too high. It's stuck open/not returning to the idle stop. If you've already cleaned the throttle body and it's still doing this then the internal mechanism is probably shot and you'll need to replace it.

Been there done that. This is one of the exact things you'll see with a failed bosch ETA.

johnboy77 · Post by **johnboy77** » 11 Jan 2019, 19:04

Thank you. I’m leaning towards the same.