2002 S60 Rough idle but smooth at higher RPM

[quietcoolone]

You mentioned that once you were in the garage you could smell stink of exhaust fumes-just exhaust smelly, or rotten egg-catalytic converter dying smelly? Granted you are currently running lean, but misfires and a not-leaned out combo will cook a cat. Also, if there is excessive backpressure at idle, it could possibly cause poor scavenging at idle and a funked-up fuel mixture..

The exhaust smells whenever engine runs, but i wanted to make you aware of that detail. It does not smell like rotten eggs just lots of fumes, the type that makes your eyes water.
if by backpressure you mean louder than normal tailpipe then yes.. it sputters at idle, but normal at higher RPM's.
BTW, intake manifold pressure was around 22hg

Thanks

[draser]

Pretty good info. Manifold pressure of 22" Hg is at the top of normal range for a NA engine. Comparing your info to my 2.5l turbo engine (due to lack of NA info) few things jump out: a) your MAF is 4.54g/s (after conversion) mine is 2.6 g/s; b) your load is 15.3% mine 11.8%; and c) I have throttle at 12.2 and pedal at 7.8 all at idle (668 rpm). Again, not sure how close these numbers are between NA and turbo, but MAF is over reporting which generates the positive fuel trim, and the cat is somewhat clogged. I would unplug MAF and read fuel trim to see if it comes down.

[quietcoolone]

Pretty good info. Manifold pressure of 22" Hg is at the top of normal range for a NA engine. Comparing your info to my 2.5l turbo engine (due to lack of NA info) few things jump out: a) your MAF is 4.54g/s (after conversion) mine is 2.6 g/s; b) your load is 15.3% mine 11.8%; and c) I have throttle at 12.2 and pedal at 7.8 all at idle (668 rpm). Again, not sure how close these numbers are between NA and turbo, but MAF is over reporting which generates the positive fuel trim, and the cat is somewhat clogged. I would unplug MAF and read fuel trim to see if it comes down.

Here are the numbers from cold start with MAF connected/disconnected (hunting for idle the entire time MAF was disconnected)
FuelSys1 CL-FAULT/OL-DRIVE
Load_pct(%) 30.2/ 1.6
SHRTFT1(%) 25.0/ 0.0
LONGTFT1(%) 25.0/ 18.0
MAP(psi) 7.0/ 3.2
RPM 896/ 837 (hunting)
SparkADV 14.0/ 10.0
IAT(F) 55/ 40
MAF (lb/s) 0.01/ 0.00
TP(%) 5.1/ 1.6
O2B1S1(V) 0.690/ 0.425
SHRTFTB1S1(%) 24.2/ -12.5
O2B1S2(V) 0.015/ 0.715
ECT (F) 78/ 185 degrees (huge change in less than 3 minutes)

prior to today, with MAF disconnected (car running) the engine would run at a higher RPM but not hunt for idle.

Here's some Freeze Frame data
DTCFRZF P0171
FuelSys1 OL-DRIVE
Load_pct(%) 15.7
SHRTFT1(%) 0.0
LONGTFT1(%) 50.0
MAP(psi) 3.3
RPM 1605
VSS (mph) 47
ECT(F) 186

[precopster]

I was going to say the MAF reading is too low however I'll have to check it on my Denso 2000 V70 when I have a moment.

ETMs can cause your symptoms even with good films and 2.9% variation because of a failed or failing logic board.

[quietcoolone]

I was going to say the MAF reading is too low however I'll have to check it on my Denso 2000 V70 when I have a moment.

ETMs can cause your symptoms even with good films and 2.9% variation because of a failed or failing logic board.

For some reason i get the same MAF reading (0.01) from my 2004 S60 Turbo.
As for the ETM, that is also very possible.. thanks.

[draser]

What about switching gears for a sec, and look at fuel delivery and compression. Did you spray aroung the fuel injectors when you tested for leaks, I believe at this mileage the seals are toast. The other thing is the injectors have developped a film that prevents fuel delivery at full rate. At this mileage you may have to get them out and have them cleaned, but I'd still throw some strong cleaner in the tank to see if it makes the slightest difference. I'd take them out anyways just to see what they and the seals look like. The second thing "due" to this engine is a compression test with a rented gauge.

[quietcoolone]

What about switching gears for a sec, and look at fuel delivery and compression. Did you spray aroung the fuel injectors when you tested for leaks, I believe at this mileage the seals are toast. The other thing is the injectors have developped a film that prevents fuel delivery at full rate. At this mileage you may have to get them out and have them cleaned, but I'd still throw some strong cleaner in the tank to see if it makes the slightest difference. I'd take them out anyways just to see what they and the seals look like. The second thing "due" to this engine is a compression test with a rented gauge.

OK.. new developments.
Earlier today I had to move the car out the garage and notice some oil on the floor.. jacked her up to inspect and found that the passenger side drive shaft and surrounding areas were splattered with oil. I first thought it was transmission oil leaking though the seal, but quickly realized it was motor oil. I then cleaned the area as best i could and started her up. Got back under there to check for leaks--- nothing--- i then ask my son to rev the engine up and as soon as he did oil began to splatter.
I could not tell immediately where it came from but soon realized that this is the same engine used in turbo models and the oil was coming where the turbo return line would connect.
here is a picture of what i'm talking about.
Anyway, Volvo sells a plug for that hole, part number 8687868 $4.23
Went to the local dealership and picked one up. The problem is you have to hammer it in but because of space limitations i was unable to get enough leverage.
Looked around the garage to see what i could use and found this battery post shim which fit perfectly and required little pounding. I believe that issue has been resolved!!!
Started her up and immediately heard a whistle sound, sorta like an air leak. Upon further inspection i could hear it coming out the dip stick hole (i had removed the dip stick to avoid breaking it). Put the dip stick back in and began to hear a squealing sound (as if it was a belt). I had read about this before so i removed the dip stick and the squealing sound disappeared.

I wonder if this crankcase plug blew out a result of PCV clog and built up pressure in crankcase?
t is clear now that i have to fix this PCV problem and i may have to go back in there and check.
My question to you experts is: will a clogged PCV cause a lean condition (rough idle) or the aforementioned symptoms?

Thanks

[quietcoolone]

What about switching gears for a sec, and look at fuel delivery and compression. Did you spray aroung the fuel injectors when you tested for leaks, I believe at this mileage the seals are toast. The other thing is the injectors have developped a film that prevents fuel delivery at full rate. At this mileage you may have to get them out and have them cleaned, but I'd still throw some strong cleaner in the tank to see if it makes the slightest difference. I'd take them out anyways just to see what they and the seals look like. The second thing "due" to this engine is a compression test with a rented gauge.

i cleaned the injectors and replaced the o-rings-- i also had a spare set of injectors (non- turbo) and nothing changed.
please read my new post and advise.. thanks

[precopster]

If this were a turbo I would say no to causing a lean condition however it may alter the perceived metered air by the MAF therefore changing throttle angles to create a rich condition.

How old are O2 sensors by the way?

[quietcoolone]

If this were a turbo I would say no to causing a lean condition however it may alter the perceived metered air by the MAF therefore changing throttle angles to create a rich condition.

How old are O2 sensors by the way?

I'm not sure how old they are, but it appears that they may have were replaced .
Is there a reason for asking?