P0171 Nightmare finally diagnosed!
 

Okay, I was driving home when all of a sudden my engine started "whistling." It sounded somewhere between a bearing on a the serpentine belt pulley, the belt slipping, or a vacuum leak. I could not figure out where it was coming from but it seemed to go away when I pressed on the fuel rail. I also noticed a small oil leak on the passenger side of the engine when I popped the hood which I had not seen before.

I searched and found all kinds of theories about how to fix the problem before running across one that actually helped. The good news is, this falls under the federal emission systems extended warranty so I am going tomorrow to get it fixed for free at the dealer. If only I had known before wasting all the time and effort replacing injector gaskets, cleaning injectors, cleaning the MAF sensor, cleaning the throttle body, etc.

The problem is in the crankcase ventilation system. The pressure builds up and causes the whistle as it is releasing the pressure. The way to diagnose it is simple. With the engine running, pull your dipstick. If you hear the pressure escaping, and the whistling goes away, that is your problem.

I hope this helps save somebody a lot of time and frustration. I have been dealing with this for weeks now! BTW, the service manager knew exactly what I was talking about as soon as I started explaining it. Apparently this is common. I cannot believe something so common was so hard to get an answer to, and the other solutions were expensive and time consuming, even for a DIY'er. Props to the guy who posted this and saved me. I cannot find the link again or I would give better props.

Ok, first of all, I would like to know what model and year car you have. Secondly, I would really be interested in knowing if you were able to get your PCV system serviced by a stealer for free. :eek:

2006 year + S40.

not sure about that emission law, never heard of such and having a dealer do work for free.

2 yrs, 24k for everything emissions related (which is just about anything) but that's covered under the new car warranty anyway).
8 yrs, 80k for;Catalytic converters, ECU's,and Onboard Diagnostic computers (OBD).

PVC systems fall in the first category.

It's a shame really- I was kinda looking forward to the collective screams of 10's of thousands of Volvo owners who have paid for, or replaced their own, system.

Yeah i have had many cats replaced for free some car manufactures even do 10 yr 100,000 on the cats and other stuff vw and toyota that i know of. I think it is a if you dont ask we wont tell u kind of think because i have had people who have been charged even though it should of been covered for free.

is that a federal law?

yeah in the usa federal mandated. i did not read the whole thing but this site seems to sum it up. i just typed in "government mandated emissions warranty" into google. u dont have to be the original owner either. might just be parts

http://www.epa.gov/oms/consumer/warr95fs.txt

I guess 17 years and 200,000 miles kinda knocks me out of the park. LOL

Sorry for not clarifying earlier that this is an 07 s40 2.4i with 60k miles. I bought it from someone who bought it certified pre owned so had extended warranty but that ended in January, Volvo extends the warranty though for emissions an yes there is a federal regulation regarding emissions as mentioned. I had my cats replaced by the dealer on my chevy tahoe about 8 years after purchase and 75k miles on it. The dealer was Roger Beasley Volvo in Georgetown and my service advisor is Joe, I recommend them highly.

Oh yeah, to clarify, Joe said it was covered by CPO but even if I didn't have that Volvo would have covered it, so yes, the repair was done for free. In fact I dropped it off Friday morning at 8:20 and picked it up at 1:00 p.m. the same day! She runs as good as ever, much quieter, and no more "check engine" light. Now to sell her before the next thing goes wrong!

i have just bought a s40 2.4i 2008 model and that stuipid light comes on, i plug my computer on and it says system to lean bank 1. wtf?

Joel, best to start a new thread. "lean bank 1" means your engine (being a straight 5 and not a V6 it only has bank 1) is running lean and the system can't compensate. Usual causes are air leaks - vacuum lines, intake tubing so do a visual inspection. After that you can check how clean your MAF, idle air valve and ETM (throttle body) is. Could also be a sensor somewhere but there should be additional codes if that's the case.

What is the actual fix?
 

What is the actual fix? You’ve only said how to diagnose the problem. This is exactly what’s wrong with my XC60, but I don’t know how to fix this. Please help.