05 V70 NA, "reduced engine performance" Topic is solved

[850 LPT]

Hi All,

Yesterday this message popped up while driving to work. It freaked me out at first but then I didn't noticed anything different while I was still on the highway. But when I took off after a red light, the car bogged down for a second after shifting (this is a manual car by the way), and that did freak me out. Then I also noticed a slight hesitation every now and then, almost like what you would get from a misfire.
Leading up to this I also had a "engine system service required" message come on. It started intermittently a couple of weeks ago but now was on pretty much permanently. Could this be related?

Unfortunately, I don't have a VIDA/ DICE setup yet, but this problem may just push me into getting it. I am dropping the car off tomorrow at my indie's shop, but I was wondering what I can expect. What could be wrong with these kind of symptoms? I'm sure I'm not the only one who had this happen. The car has 133k on it now.

Thanks, Dirk

[oragex]

Careful with what the shop says. Unless that's a very Volvo knowledgeable place, these are the kind of electrical issues hard to diagnose and they can come up with random repairs.

The first thing, I'd measure the alternator output and check the cables around it
Then perhaps, I'd go in this order (google up for details): ECM (check the cooling fan works and there is no corrosion at the bottom where the two modules are plugged - a special too is needed to remove the modules), CEM (affected by water ingress).

Also make sure to do this mod on your non turbo

[850 LPT]

Thank you, oragex, that's all great information, much appreciated! Exactly what I was looking for.

As far as the mechanic, I really trust this guy. He is a former Volvo mechanic who has his own business, AND he is very honest. I've known him for a long time now and he is the only mechanic who is allowed to touch my cars. Honestly, I am not sure I would drive these cars if I didn't have someone like him around. I am very aware of the problems one can have with a non Volvo person.

Unfortunately, I will not have much time to test the things you mentioned before I bring the car there tomorrow afternoon. But this gives me some discussion points for sure. And I will do that air box thermostat mod when I get the car back.

[oragex]

If you run out of ideas, there is also this less common but really hard to find issue with a worn crankshaft pulley. Doesn't seem to cause the same issue as yours, but you never know

viewtopic.php?f=9&t=58219

[precopster]

If you don't have a Vida/Dice you can still read any obvious engine or transmission codes with an ELM 327 paired to your smart phone for about $20 or with an inexpensive Autel base model scanner for not much more.

Way too many directions to go in without a clue from the onboard diagnostics.

[850 LPT]

Thanks, I do own a Foxwell scanner which picked up nothing, no codes. Also, I do not have the CEL on.

I dropped the car off at my indie's shop yesterday and I'm sure the first thing he is going to do is hook up his VIDA/ DICE. Since he has a Volvo shop I'm sure he has the real deal too.
Unfortunately, I don't have the time right now to dive into the VIDA/ DICE world, but eventually I will. I know it makes sense, especially because I now own two P2's.

[850 LPT]

Problem is fixed, it ended up being a faulty clutch positioning sensor, and the repair was relatively inexpensive. I guess it's a real problem when the ECU doesn't know what the clutch is doing

[abscate]

I've noticed when the ECU resets or battery disconnect the manual is very different to drive, kind of like you are a rookie stick shift driver