2007 v70 2.5T Codes: P2188, P0101, & P2178

generationsbsq · Post by **generationsbsq** » 07 Jan 2023, 18:30

2007 V70 2.5T stalled on my daughter last week at a stop sign. She said it stumbled, shook, recovered, then shut off. I drove it immediately after and it ran fine. No CEL came on.

Parked it then checked it a day later. From cold start it had a very rough idle, stumbled, recovered, and stalled. Restarted and it did the same. I cleaned the MAF sensor (bought MAF cleaner), allowed it to dry, reassembled, and restarted. Idle was WORSE. Still no CEL. Left it 3 more days til this morning.

Cranked it up and it idled fine. Finally the CEL came on. My domestic OBD2 wouldn't read the codes so I drove it to Advance Auto (about 7 minutes from my house) where they have a Volvo enabled reader. Pulled stored P2188 and pending P0101and P2178 codes this morning. It drove fine to and from Advance. Idled fine in the driveway.

I have not cleared the codes to see if they come back. Should I?

Everything I've read points to various parts such as the MAF, fuel filter, fuel pressure sensor, and the PCV system. None of these parts are particularly cheap (at least from FCP).

Any suggestions on how to further narrow it down or actual fixes?

Thanks!
cbb

MDK · Post by **MDK** » 07 Jan 2023, 20:21

So.. 2188 is too rich fuel...2187.. too lean fuel. 0101 stall. It's good you haven't cleared the codes yet. The first 2 sounds like what they call fuel trim issues . The last one points to the maf sensor.. cleaning maf sensor doesn't always fix them and that may not be the problem I think I'd would look at cleaning the throttle body assembly. They get sticky. Also.. points to vacuum leak or leaks.. also in your post you stated 2178?.. that's a cylinder miss fire code.. MDK

Post by **cn90** » 07 Jan 2023, 22:31

Sudden stalling in P2 2.5T, in my experience:

1. Search forum for PEM unit. Yiu can buy a good used PEM on ebay (look
for newer date of mfg) for about $50 and swap it to see what happens.

2. Dirty Throttle Body, cleaning this is free (well, you need Carb Cleaner, afew dollars at
auto parts store).
I wrote a DIY in XC90 forum.

93SCMax · Post by **93SCMax** » 08 Jan 2023, 06:30

Good advice provided so far, but I'd also recommend checking the electrical connector to the MAF, and the pins on the MAF for corrosion. This is an easy check, and that sensor could still be the issue.

Good luck.

generationsbsq · Post by **generationsbsq** » 08 Jan 2023, 18:12

MDK wrote: ↑07 Jan 2023, 20:21 also in your post you stated 2178?.. that's a cylinder miss fire code.. MDK

I went back and checked the scanner. Correct codes are: 0101, 2188 (stored and pending), & 2178. Per the scanner, 2178 is "System too rich off idle bank 1.". Photos attached. See also my update below. I'm more confused now.

generationsbsq · Post by **generationsbsq** » 08 Jan 2023, 18:37

**UPDATE*

I took it out this evening to try and get it to stumble, rough idle and stall. Cranked right up, idled fine. I let it sit and idle for about 5 minutes and revved it a few times. It settled into a normal idle each time. Took it for an "in town" drive with starts and stops as well as some 35-45 mph driving. It drove great.

Next I took it out to 60+ mph with hard acceleration, steady cruising, and 45 to 70 speed ups and slow downs. Ran like a scalded cat. Always settled into a regular idle when coming to a stop.

Pics of real time data is attached.

I haven't cleared any codes yet.

Thoughts?

generationsbsq · Post by **generationsbsq** » 08 Jan 2023, 18:42

Also did the glove test. Limp at idle. Minor suction at 3000rpm.

It was suggested to do this on another forum to test whether the PCV system is working properly.

MDK · Post by **MDK** » 09 Jan 2023, 13:42

From your last post and from what you're saying everything seems good. Just make sure to run premium.. 93 octane or higher. On a good day your dipstick should have -5lbs of pressure. Clear the codes and see if they return. MDK