Probably a vacuum leak. Check all hoses are nice and tight.

 

took it to the dealership and they did a leak test and found nothing! At least they didn't charge me! But check engine light came back on a week later same code!

 

A quick google search suggests that the car is running lean. Could be your air supply. I would make sure the pvc clamps aren't loose and leaking. then check the charged air pipes for the intake manifold. Makes the manifold is not loose either while you are at it. There are some small hoses on the manifolds left side. There appears to be three but in reality it's just a line being routed by a welded guide to the manifold. IN the middle of the little cluster is a hose that should be connected with a clamp to the manifold. That's another thing to check as well. IF all of those are properly connected just keep walking backwards in the air system checking all air pipes. the over pipe front and rear connections can be loose, I've not tightened them down properly and full boost hits and PHWOOSH. coupling or something blew off. The front coupling of the over pipe can be a weak spot.

Give those things a try Like I said some ob2 generic code for p2177 says the bank is running lean. If it's not stumbling weird like it doesn't have enough fuel then it must be the air supply.

 

I have the same problem!

Hi,

I recently bought my first S60 R (2004) and I am experiencing the exact same behavior with the P2177 code. I had the Volvo dealership perform a full diagnosis when I purchased the vehicle from a private party and the dealership couldn't find anything wrong.....figures the P2177 code magically disappeared before I went in for my appointment. Now 2 weeks later the engine light came on again - and the P2177 code returned as well.

So I'm very curious to know what your resolution was and what you learned.

My two cents is that I noticed the light come on while I was down-shifting into 4-5 RPM as I exited the freeway. Immediately afterwards I could definitely notice a big difference in the turbo's boost. Currently it seems like it doesn't launch me forward as dramatically as it did before the light turned on...It's possible that I just became paranoid after seeing the light come on, but the previous comment "the over pipe front and rear connections can be loose, I've not tightened them down properly and full boost hits and PHWOOSH. coupling or something blew off. The front coupling of the over pipe can be a weak spot" sounded like it might be backing me up and could be on the right track? Hoping for good news...

 

I recently replaced my fresh air pipe with a snabb setup. My original oem fresh air pip was all nasty and gross from ptc housing and parts were corroded and the seals weren't sealing 100 percent. I also replaced all the vacuum lines to the tcv and all of those were getting hard and cruddy. all new silicon and the snabb pipe, no leaks no codes. Car runs like a top with 230xxx on the clock.

Go through the air system all the way to the intake gasket. tighten everything make sure everything is seated and not rubbing or stretched. even small leaks and imperfections can seriously effect the system. small slightly unseated coupling will ruin how the car runs.

 

Ok, update to the P2177 code:

I ended up taking my car into the dealership for an $80 plug in their scanner....but I think it actually paid off.

The Volvo code certainly was more precise and definitely identified the exact problem.

Autozone code P2177:

Definition - system too lean off idle bank 1;
Explanation - failed MAF;
Probable Cause - Low fuel pressure, vacuum leaks on engine, failed heated oxygen sensor

Volvo Dealer's Code ECM-280A (Exhaust control module):

Front heated oxygen sensor bank 1 - faulty signal

The dealer quoted me $500 to replace the bad front O2 sensor....said it had fried the wires. Instead, I took it home and looked at the O2 sensor myself...and sure enough the dealer was right, there was a very obvious 1.5" long tear in the black (unshielded) section of wire. It was clear that it had been touching the very hot part of the exhaust system directly beneath it...and melted through and exposed/ruined the wires.

For $100 I bought a Bosch replacement O2 sensor at Autozone and replaced it myself. However, I also salvaged the 8" woven metallic heat-shield sleeve from the bad sensor and slipped it onto the black part of the new wire where the previous one had melted. The attached clips on the black section of the new wires should help keep the wires out of reach of the hot surfaces but now I've got double the protection by using the extra sleeve.

That was yesterday and today the CEL is still on...but I've heard it may take a day or two for the CEL to go away on its own. Fingers crossed.

Now about those codes....has anyone figured out how to get the same "more precise" codes as the Volvo dealership?

 

Volvo's VIDA software will give you those codes.

Sent from my iPhone using Tapatalk

 

Volvo's VIDA software will give you those codes.

Correct but you also need the DICE hardware to plug the VIDA computer into the car.

Get one from AliExpress.com

 

Newest update for everyone is it was my mass airflow sensor. I had replaced it about 8 months ago and it just went bad again! Long story short it was an aftermaket! I am learning everyday to never put that crap on this car! Which has me confused because I read on here about so many of you all changing over things to get more horsepower and other things but no problems!?!

 

The "add HP" stuff is just an ECU tune plus simple "plumbing". Not fancy sensors...

 

A quick google search suggests that the car is running lean. Could be your air supply. I would make sure the pvc clamps aren't loose and leaking. then check the charged air pipes for the intake manifold. Makes the manifold is not loose either while you are at it. There are some small hoses on the manifolds left side. There appears to be three but in reality it's just a line being routed by a welded guide to the manifold. IN the middle of the little cluster is a hose that should be connected with a clamp to the manifold. That's another thing to check as well. IF all of those are properly connected just keep walking backwards in the air system checking all air pipes. the over pipe front and rear connections can be loose, I've not tightened them down properly and full boost hits and PHWOOSH. coupling or something blew off. The front coupling of the over pipe can be a weak spot. Give those things a try Like I said some ob2 generic code for p2177 says the bank is running lean. If it's not stumbling weird like it doesn't have enough fuel then it must be the air supply.

Hey at the end you mentioned a weird stumble . My 2004 Volvo s40 t5 every now and again will do that very thing what could that be ???