2002 S60 Rough idle but smooth at higher RPM

draser · Post by **draser** » 08 Jan 2015, 06:54

Well, being as it may, the PCV needs done. You cleaned the ports but reused the cartridge, so I'll speculate that some crud got dislodged and blocked one of the top ports. Not sure if you cleaned the oil return port in lower block, drop the pan, etc. When reassembling gasketed surfaces I'd 2-check surfaces to be very clean, I normally wipe them with solvent after cleaning all visible material. No nicks or scratches are allowed. I'd borrow a torque wrench for manifold. Then we'll see how she runs.

quietcoolone · Post by **quietcoolone** » 08 Jan 2015, 07:27

draser wrote:Well, being as it may, the PCV needs done. You cleaned the ports but reused the cartridge, so I'll speculate that some crud got dislodged and blocked one of the top ports. Not sure if you cleaned the oil return port in lower block, drop the pan, etc. When reassembling gasketed surfaces I'd 2-check surfaces to be very clean, I normally wipe them with solvent after cleaning all visible material. No nicks or scratches are allowed. I'd borrow a torque wrench for manifold. Then we'll see how she runs.

I spent at least 8 hours reading up on the PCV service and realize i may have not properly cleaned the bottom engine port. This port curves downward into the pan and that pathway may still be clogged. I will remove everything again today and make sure to give it a thorough cleaning.
I don't plan on dropping the pan but will change the oil.
I do have a torque wrench--- do you know the ft/lbs for these bolts?
Despite not having torque setting for the intake, i'm 100% certain that there are no air leaks. I have sprayed excess amount of carburetor clean on and around it with no change in engine idle and will do the same today after completing the PCV service and hopefully my next post will have encouraging news.
Thanks again for all your help.

draser · Post by **draser** » 08 Jan 2015, 07:54

I'll get the mani torques tonight. I'd consider dropping the pan for several reasons, based on mileage of the car: a) clean pcv port; b) clean sludge from pan; c) clean oil pick up and replace o-rings to prevent a "low oil pressure" event later on. Up to you. Cost is not that great, only o-rings and liquid gasket; it's mostly labor. Main problem is this cold if there's no heated garage. I have mine half apart in the garage and don't wa t to touch it it's that cold.

quietcoolone · Post by **quietcoolone** » 08 Jan 2015, 09:36

draser wrote:I'll get the mani torques tonight. I'd consider dropping the pan for several reasons, based on mileage of the car: a) clean pcv port; b) clean sludge from pan; c) clean oil pick up and replace o-rings to prevent a "low oil pressure" event later on. Up to you. Cost is not that great, only o-rings and liquid gasket; it's mostly labor. Main problem is this cold if there's no heated garage. I have mine half apart in the garage and don't wa t to touch it it's that cold.

All valid points especially the mileage.
I will consider doing this job as well.
My garage is not heated but i do have a portable heater capable of getting the temps up to 62, so that is not much of a concern.

draser · Post by **draser** » 08 Jan 2015, 17:56

Intake bolts torque is 20 Nm or 15 ft/lb. Good luck!

quietcoolone · Post by **quietcoolone** » 08 Jan 2015, 18:55

draser wrote:Intake bolts torque is 20 Nm or 15 ft/lb. Good luck!

Had a hard time taking the pan down-- vehicle frame (forward end) is bent back a little so it makes it difficult to lower the pan without tilting it too much.. i finally got it off and cleaned. Tomorrow i will get the o-rings and gasket from dealer. May not be able to put things back together until Sunday but will keep you posted.

Thanks for the torque data.

draser · Post by **draser** » 08 Jan 2015, 19:27

Forgot to mention about tightening the manifold, I'd do it form center outwards, in two 10Nm stages. Pan bolts if they're 10mm heads normally take 10Nm torque criss-cross tightening. Just thinking out loud..

quietcoolone · Post by **quietcoolone** » 09 Jan 2015, 05:24

Thank you for the tip

quietcoolone · Post by **quietcoolone** » 12 Jan 2015, 16:51

Update:
Before anything let me add a few pointers on removing and replacing the oil pan. I know its been covered on this site but these two points were key got getting it off and back on:
1. Drive the vehicles onto ramps and remove the two 19mm bolts securing front motor mount to frame. Use jack to raise engine. (i used a 4" long piece of 2x3 and placed it under the AC Compressor.
2. To create extra room, remove power steering line clamp from frame then move it up and away from its retainer.
As for the issue.
I used my air compressor to blow crud from the vent hole inside oil pan, replaced seals on pan and closed it up. (Added new oil and filter).
Made sure all hoses, trap and vent holes on engine were cleaned and that there were no oil leaks.
Put everything back together and fired her up.
The engine ran much better so i took it for a spin and monitored some data.
After 5 minutes engine went from CL to CL-FAULT and remain that way, however fuel trims remain normal (SF -2.3) (LT 6.3) I also notice a little smoke coming out of the oil cap and dip stick. is this normal for this engine?
It also has a P0420 pending.
Will drive on hwy tomorrow and will post some more numbers.

quietcoolone · Post by **quietcoolone** » 14 Jan 2015, 19:47

Update.
The idling issue appears to be fixed, however the car will run in CL for a few minutes then Close Loop-Fault. CEL is now on:
ECM-4201 Three way catalytic converter efficiency. Power deterioration
Condition
After Start-up, the ECM checks the efficiency of the TWC by switching between rich and lean fuel/air mixtures. The the change-over is made, the signal from the rear heated OS is checked and the time taken for the probe to switch. The DTC is store in the ECM registers that the rear heated OS switched too quickly.
Possible source
Air leakage in the exhaust system
one or more damaged injectors
Damaged Catalytic Converter

Freeze Frame Data:
Freeze Frame delay time: 90.11ms
Time after engine start: 20.65 min
Ambient Temp: 2.04C
Ambient Air Pressure:1025.74 hPa
Vehicle Speed: 111 km/h
Engine Speed: 2349.25 rpm
Intake Airflow Rate Gn: 0.58 g/rev
Intake Manifold Absolute Pressure: 559.13 hPa
Engine Coolant Temperature: 86.12C
STFT data: 0.99
LTFT data:1.07
Close Loop Operation: Yes
Fuel Cut off ECM: No
Driving Cycle: No
Warm up Cycle: No
Engine Coolant Fan: Off
A/C Demand: No
A/C Compressor Active: No
Brake Pedan Switch: Off
Evap Active: No
Cruise Control Active: Yes
Canister Close Valve: Opened
Fuel System Status bank 1: LR: Close Loop operating with two sensors
Battery Voltage: 14.4 V
Incar Temperature: 195

Other observations while cruising 65MPH on Hwy
02 Sensor graphs:
1. 02B1S1(V) pretty steady between 0.465 - 0.510
2. O2B1S2(V) switching between 0.04 - 0.825
How could B1S1 (pre-cat) produce a straight line and B1S2 (post cat) product a Sine-Wave pattern?
Isn't this opposite to conventional wisdom?
I also notice that fuel trims remain below 10%
the front sensor unlike the rear is a wideband Air/Fuel Sensor (not sure if that has anything to do with waveform.
Thanks

2002 S60 Rough idle but smooth at higher RPM

Re: 2002 S60 Rough idle but smooth at higher RPM