In frustration...a question to the experts out there!

MACKJ · **Posted:** Thu Nov 16, 2006 10:17 pm

I have two problems which I think may be interrelated, and I would appreciate any input as to the root cause(s).
The first is oil in the CAC hoses. I installed a Provent about four months ago and have travelled approx 5000kms since the install. The return line from the Provent to the factory tap in (downstream of the compressor) is bone dry, therefore the Provent is working as it should with no CCV oil going back into the intake air stream. However when checking the CAC hoses (daily) I find oil in the hoses…enough to create a ring of oil at the point where the hoses join the CAC connections and a splatter of oil through the hoses. I clean the oil from the hose, it is back the next day. I do 99.9% city driving, rarely using high throttle application. Where is this oil coming from?? From the turbo oil seals??
Secondly, I have had a disconcerting vibration/ noise for about the last 16000 kms that has progressively worsened over time. The vibration is most pronounced between idle and about 1200 rpm whereby the diesel engine noise drowns it out but I am sure it is still there, increasing the overall NVH of the engine during city driving. At much higher revs/ highway speeds the engine is quiet (for a diesel!). The best way I can describe the noise is like increased diesel knock, creating a drone like sound together with increased vibration through the steering wheel and floor pan (the right hand side of the vehicle= passenger side in the USA). The tacho shows a dead steady idle but the engine is not smooth at low revs. The vibration and noise is substantially worse when the engine is under load with the air con on and you can feel the engine shake a little when the air con clutch engages/disengages.
When I come home from work each day, and I let the engine warm down in the garage, if you listen under the vehicle after about a minute the engine vibration/tone physically seems to smooth out a little. I think this is when the EGR valve closes.
Jeep have given up on the problem after changing out the engine mounts and looking for any obviously contact points between the body and power train components.
I changed the factory muffler to a straight through Aeroturbine unit which made little difference.

The fact remains that the engine was much smoother and less noisey for the first 8000kms, now it sounds more like a tractor from inside the cabin.
My question is could these problems be caused by a near fully closed flow control valve (anti run on valve) creating the two situations?
With the valve almost shut excessive back pressure is put on the turbo compressor creating a vacuum behind the turbine wheel and therefore drawing oil past the seals.
Also with the FCV almost shut the engine is mostly getting hot EGR gases as “fresh” air and this increases the knock in the engine.
Your comments/advice pleeeeease!

Pablo · **Joined:** Thu Feb 02, 2006 10:06 pm **Posts:** 1201

I am beginning to think failing FCV valves are responsible for everything that the EGR valve is not-- namely the tranmission shudder. How much to just make them change it I wonder? I wonder if the programmed ECU from inmotion that disables the EGR will also keep the flow control valve off? Seems like it would. I am beginning to think buying that maybe the best investment yet. If nothing else, you could switch ECU's and test all these theories that we have about the FCV valve, etc-- by turning it off. Then stick the other ECU in and see if the problems return.

Of course if you were Chrysler you could do the same thing at the factory and actually troubleshoot crap and fix it instead of abandoning customers and dealers to their own devices!

MACKJ · **Posted:** Fri Nov 17, 2006 12:29 am

Pablo wrote:

I am beginning to think failing FCV valves are responsible for everything that the EGR valve is not-- namely the tranmission shudder. How much to just make them change it I wonder? I wonder if the programmed ECU from inmotion that disables the EGR will also keep the flow control valve off? Seems like it would. I am beginning to think buying that maybe the best investment yet. If nothing else, you could switch ECU's and test all these theories that we have about the FCV valve, etc-- by turning it off. Then stick the other ECU in and see if the problems return.

Of course if you were Chrysler you could do the same thing at the factory and actually troubleshoot crap and fix it instead of abandoning customers and dealers to their own devices!

I definitely agree on your last comment. In my ramblings I also negated to add that I have the "dreaded shudder" occasionally, however I have always thought this to be related to fuel/injectors or airflow etc in other words something to do with the engine not the tranny...my opinion. Maybe the shudder is also caused by the FCV sticking??! I really am at the stage of clutching at straws. If I unplug the FCV will I be able to test my theory?

MrMopar64 · **Posted:** Fri Nov 17, 2006 1:42 pm

If you unplug the FCV, it will set a P-code for FCV Circuit low/signal not plausible/no load on the power stage. If I remember correctly, it will disable EGR but I am not sure if it will cause a limp home or not. You can try it all you want to, but the shuddering problem with the trans is an inability of the torque converter to handle the torque of the engine at the low RPMs it produces them at.

I know nothing really of how the InMotion people accomplish their turning off the EGR so I cannot say for certain whether or not the method in which they do it is good for the engine.

The engine knock you describe could be from some carbon build-up in the cylinder. Take it out on the interstate or a road where you can get on it, and give it the good old Italian tune-up -- beat the heck out of it for 20 minutes or so to clean it out. Cylinder pressure during WOT (peak power & peak torque) is about 160 bar, so it'll get all the gunk out. THe first few times you do it, you'll probably see a nice cloud of smoke.

Wilmo · **Posted:** Fri Nov 17, 2006 8:17 pm

MACKJ wrote:

I have two problems which I think may be interrelated, and I would appreciate any input as to the root cause(s).

The first is oil in the CAC hoses. I installed a Provent about four months ago and have travelled approx 5000kms since the install. The return line from the Provent to the factory tap in (downstream of the compressor) is bone dry, therefore the Provent is working as it should with no CCV oil going back into the intake air stream. However when checking the CAC hoses (daily) I find oil in the hoses…enough to create a ring of oil at the point where the hoses join the CAC connections and a splatter of oil through the hoses. I clean the oil from the hose, it is back the next day. I do 99.9% city driving, rarely using high throttle application. Where is this oil coming from?? From the turbo oil seals??

I also see what you do with regards to oil in the hose, even though the Pro-vent is working 100% and the return line to the air intake is clear. Can only assume its from the turbo seals or does someone else have a valid explanation?

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

A couple of us have the same problem and we both have Provents installed and working correctly. Both myself and RFCRD have posted quite a bit on this subject. My Provent has a clean output hose, and has a 1/2" drain hose attached. At 25K miles, it currently collects about 12 - 14 inches of blowby engine oil in the Provent drain tube at 5K mile intervals. At the same interval, I have a thin, but solid black coating of engine oil inside the turbo hose on the passenger/turbo side of the engine, and the intake side CAC hose is heavily tiger striped. I have cleaned both hoses many times and 5K miles ago I removed both of them, cleaned them thoroughly and they were bright orange until recently. Oil is Mobile 1 5W-40 CI4 diesel rated synthetic.

No idea why some turbos blow plenty of oil past their seals and others don't. Mine has done it since about 2500 miles, which is when I first installed the Provent. I use Mobile 1 5W-40 CI4 rated diesel oil and change it at 5K intervals as well as a Mopar factory diesel filter. So far, 2 EGR valves replaced, lots of TCM/ECM flashes. Plenty of WOT and about 50 miles per day regular use. Engine itself runs very well.

Wish I could help on the leaking turbo seals but no idea what's going on. Perhaps just the luck of the draw. Difficult for me to imagine how this kind of oil in the intake system will not cause problems down the line.

RFCRD · **Posted:** Sat Nov 18, 2006 1:44 am

Wilmo wrote:

MACKJ wrote:

I have two problems which I think may be interrelated, and I would appreciate any input as to the root cause(s).

The first is oil in the CAC hoses. I installed a Provent about four months ago and have travelled approx 5000kms since the install. The return line from the Provent to the factory tap in (downstream of the compressor) is bone dry, therefore the Provent is working as it should with no CCV oil going back into the intake air stream. However when checking the CAC hoses (daily) I find oil in the hoses…enough to create a ring of oil at the point where the hoses join the CAC connections and a splatter of oil through the hoses. I clean the oil from the hose, it is back the next day. I do 99.9% city driving, rarely using high throttle application. Where is this oil coming from?? From the turbo oil seals??

I also see what you do with regards to oil in the hose, even though the Pro-vent is working 100% and the return line to the air intake is clear. Can only assume its from the turbo seals or does someone else have a valid explanation?

Oh, no question it's the turbo seals. Don't believe there is a cure for it. I gave up on stopping the oil. Look at it now like having a chronic disease, just try to control it to the first few inches of the CAC hose. I expect cleaning the main CAC hose to be part of the normal maintenance ritual.

MACKJ · **Posted:** Sat Nov 18, 2006 6:20 am

MrMopar64 wrote:

If you unplug the FCV, it will set a P-code for FCV Circuit low/signal not plausible/no load on the power stage. If I remember correctly, it will disable EGR but I am not sure if it will cause a limp home or not. You can try it all you want to, but the shuddering problem with the trans is an inability of the torque converter to handle the torque of the engine at the low RPMs it produces them at.

I know nothing really of how the InMotion people accomplish their turning off the EGR so I cannot say for certain whether or not the method in which they do it is good for the engine.

The engine knock you describe could be from some carbon build-up in the cylinder. Take it out on the interstate or a road where you can get on it, and give it the good old Italian tune-up -- beat the heck out of it for 20 minutes or so to clean it out. Cylinder pressure during WOT (peak power & peak torque) is about 160 bar, so it'll get all the gunk out. THe first few times you do it, you'll probably see a nice cloud of smoke.

Thanks MrMopar64 for the advice.
I'll give it a go and just see what happens.
Thanks Wilmo, Ranger1 et al
I had basically convinced myself that the seals are the only place that the oil can be coming from...and you all agree. Why don't I feel comforted!!

MACKJ · **Posted:** Mon Nov 20, 2006 7:16 am

1. Disconnected the FCV electrical plug. Started the engine. Everything fine except for the "check engine" light. Test drove and the car did not go into limp mode.
2. Gave the car a few "Italian tuneup" high load, long hill climbs and found that the turbo seemed to spool up quicker (and whistled more)...engine seemed to perform better, much quicker rev response.
3. On shut down, without the FCV closing, the engine was more agricultural...shook a little more than normal but certainly shut down OK.
4. darn... oil still in the hoses after two days of running. I did clean the turbo to CAC hose after the Italian tune ups to ensure I was comparing any result with my normal day to day driving.
5. Engine still idles like a tractor with the FCV disconnected...a bit like a big six or V8 with a mild cam job.
5. Reconnected the FCV plug.
End of test

Next theory...is the EGR stuck almost fully open?? I am right in thinking that it fully opens when the engine is cold and should almost close when the engine is hot?
This vibration still seems like poor combustion but I am racking my brain as to the cause. No fault codes. Injectors seem OK, they have been checked for flow, except for the old pop test...no one in town has the Bosch test gear yet. Oops, sorry I am rambling again...

Wilmo · **Posted:** Tue Nov 21, 2006 7:46 am

Wilmo wrote:

MACKJ wrote:

I have two problems which I think may be interrelated, and I would appreciate any input as to the root cause(s).

The first is oil in the CAC hoses. I installed a Provent about four months ago and have travelled approx 5000kms since the install. The return line from the Provent to the factory tap in (downstream of the compressor) is bone dry, therefore the Provent is working as it should with no CCV oil going back into the intake air stream. However when checking the CAC hoses (daily) I find oil in the hoses…enough to create a ring of oil at the point where the hoses join the CAC connections and a splatter of oil through the hoses. I clean the oil from the hose, it is back the next day. I do 99.9% city driving, rarely using high throttle application. Where is this oil coming from?? From the turbo oil seals??

I also see what you do with regards to oil in the hose, even though the Pro-vent is working 100% and the return line to the air intake is clear. Can only assume its from the turbo seals or does someone else have a valid explanation?

I spoke to the service manager at one of our local Turbo rebuilders today (a very reputable company) and questioned him re Garrett turbos leaking oil past the seals. He didn't know anything specific about the Garretts, although when I told him I was running a Provent - he said to be VERY careful with aftermarket air/oil separators that could cause a pressure buildup in the crankcase. ie not allowing the CCV to vent properly, which increases crankcase pressure, which in turn leads to oil being pushed past the seals in the turbo. In an effort to test this theory I cleaned the intake hose of oil today, and removed the filter from my provent and will drive around with it like that for a few days to see if a) the provent still collects blow by or it comes through to the air intake and b) whether there is any oil coming from the turbo seals.

So the Provent could be causing the seal leakage? Something to consider I guess, especially if the filter in the provent is blocked up.

Ranger1 · **Joined:** Mon Oct 17, 2005 7:40 pm **Posts:** 1137

Anything that blocks the ccv tubing to the turbo intake will cause increased crankcase pressure. If your Provent hoses are not kinked, you don't have to worry about the Provent. It has a safety relief valve in the cap, set to vent to atmosphere at .78 psi differential between input and output. You can test it by squeezing the output hose from the Provent while the engine is running and you'll see oil vapor vent out from under the Provent cap immediately.

Goglio704 · **Posted:** Tue Nov 21, 2006 9:08 pm

MrMopar64 wrote:

If you unplug the FCV, it will set a P-code for FCV Circuit low/signal not plausible/no load on the power stage. If I remember correctly, it will disable EGR...

Would really like to know for sure if an inoperative FCV also disables the EGR. Seems like it would have to or the EGR wouldn't flow correctly would it?

Thanks.

RFCRD · **Posted:** Tue Nov 21, 2006 10:29 pm

Ranger1 wrote:

Anything that blocks the ccv tubing to the turbo intake will cause increased crankcase pressure. If your Provent hoses are not kinked, you don't have to worry about the Provent. It has a safety relief valve in the cap, set to vent to atmosphere at .78 psi differential between input and output. You can test it by squeezing the output hose from the Provent while the engine is running and you'll see oil vapor vent out from under the Provent cap immediately.

Just add one thing as a Provent can be used either closed-vented or open-vented. Keeping the closed-vent loop of this engine, it's still operating under a strong vacuum caused by the draft from the turbo.

Wilmo · **Posted:** Tue Nov 21, 2006 10:48 pm

RFCRD wrote:

Ranger1 wrote:

Anything that blocks the ccv tubing to the turbo intake will cause increased crankcase pressure. If your Provent hoses are not kinked, you don't have to worry about the Provent. It has a safety relief valve in the cap, set to vent to atmosphere at .78 psi differential between input and output. You can test it by squeezing the output hose from the Provent while the engine is running and you'll see oil vapor vent out from under the Provent cap immediately.

Just add one thing as a Provent can be used either closed-vented or open-vented. Keeping the closed-vent loop of this engine, it's still operating under a strong vacuum caused by the draft from the turbo.

So essentially, there's never going to be any restriction because of the provent.....or enough of a restriction to be a cause for increased crank case pressure?

RFCRD · **Posted:** Tue Nov 21, 2006 11:07 pm

Wilmo wrote:

RFCRD wrote:

Ranger1 wrote:

Anything that blocks the ccv tubing to the turbo intake will cause increased crankcase pressure. If your Provent hoses are not kinked, you don't have to worry about the Provent. It has a safety relief valve in the cap, set to vent to atmosphere at .78 psi differential between input and output. You can test it by squeezing the output hose from the Provent while the engine is running and you'll see oil vapor vent out from under the Provent cap immediately.

Just add one thing as a Provent can be used either closed-vented or open-vented. Keeping the closed-vent loop of this engine, it's still operating under a strong vacuum caused by the draft from the turbo.

So essentially, there's never going to be any restriction because of the provent.....or enough of a restriction to be a cause for increased crank case pressure?

Not unless there is an obstruction in the hose between the engine vent and the Provent. If you install a Provent with an open-vent arrangement and the exhaust hose is obstructed, the pressure relief valve will take over and relieve the over pressure.

Wilmo · **Posted:** Tue Nov 21, 2006 11:54 pm

Understood, thanks. Mine's plumbed back into the intake not venting to atmosphere and there's definitely no obstruction in the hose from the ccv to the provent.

MACKJ · **Posted:** Thu Nov 23, 2006 9:45 pm

I have recently cleaned the boost pressure/Intake temp sensor. It was completely covered with a sticky mix of oil and carbon, in other words, beautifully insulated. After cleaning I have noticed smoother operation and possible improved torque as the rig holds fifth gear much longer when going up an incline. Idle smoothness has also improved, although not to my satisfaction yet.
The question is, does the ECM re-learn parameters after a sensor clean or replacement?
Or does it have to be reset?

MrMopar64 · **Posted:** Thu Nov 23, 2006 10:57 pm

The only thing that the ECU should be learning is the zero-quantity adjustment and fuel balancing for the injectors. There shouldn't be any learning for sensors such as the boost pressure sensor/intake air temp. However, if that sensor was dirty it could throw off the learning for injectors and throw off the balancing. I'm not sure if disconnecting the battery will clear such things to start over with the learning and balancing because the ECU writes those values to the EPROM to store them - else it'd have to get the memory cleared by a StarScan (it's literally a 30-second procedure). I say disconnect the battery and give it a shot - it's free and won't hurt anything.

MACKJ · **Posted:** Fri Nov 24, 2006 1:16 am

MrMopar64 wrote:

The only thing that the ECU should be learning is the zero-quantity adjustment and fuel balancing for the injectors. There shouldn't be any learning for sensors such as the boost pressure sensor/intake air temp. However, if that sensor was dirty it could throw off the learning for injectors and throw off the balancing. I'm not sure if disconnecting the battery will clear such things to start over with the learning and balancing because the ECU writes those values to the EPROM to store them - else it'd have to get the memory cleared by a StarScan (it's literally a 30-second procedure). I say disconnect the battery and give it a shot - it's free and won't hurt anything.

Will do.
Thanks for the quick reply.

Wilmo · **Posted:** Fri Nov 24, 2006 2:38 am

MACKJ wrote:

I have recently cleaned the boost pressure/Intake temp sensor. It was completely covered with a sticky mix of oil and carbon, in other words, beautifully insulated. After cleaning I have noticed smoother operation and possible improved torque as the rig holds fifth gear much longer when going up an incline. Idle smoothness has also improved, although not to my satisfaction yet.
The question is, does the ECM re-learn parameters after a sensor clean or replacement?
Or does it have to be reset?

Where is this sensor located?

In frustration...a question to the experts out there!

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