Engine/Transmission (1998.5 - 2002) Excessive white smoke from crank case breather tube

[Tuglife]

Hello all... in the last few days, I have noticed excessive white smoke coming out from the crank case breather tube and the truck still seems to run fine. A year ago, I removed the Puker Bottle and then ran a 6' piece of heater hose from the crank case port then back along the left side of the engine exiting behind the front axle. In the past, I have noticed some smoke coming out the hose after the engine has been under a load but now while it is idling, it does it all the time. Is this something I should be concerned about?



Thanks in advance,

Nick

 

[gtwitch]

Tuglife, have you checked the coolant level or been watching that?? Also look at oil level (is it making oil or sludge because of a coolant leak into the crankcase??



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[Tuglife]

Gtwitch, thanks for the reply... I haven't noticed anything out of the ordinary. I'm going to pull an oil sample and have it checked out.

Thanks,
Nick

 

[Ram4Sam]

Another thing it could be is a vacuum leak in your hvac controls. The vac pump pulls a vacuum on the hvac unit to operate the controls for heat, cool,a/c etc. If you have a vac leak, the pump, which is vented into crankcase, draws in air through the leak and will pressurise the crankcase, which then goes out the vent tube. I had this happen awhile back, found a leaking hose (between the pump and the firewall tee fitting). No more smoke.



Sam

 

[Tuglife]

Sam, I think that is it... I have had issues with the a/c for a while now. How difficult was it to access the pump? Do you know where I might find a picture or drawing of the pump?

Thanks,
Nick

 

[Ram4Sam]

The pump is right below the injection pump, with the power steering pump hanging off the back of it. There is probably not an issue with the pump. The vac line off the side of the pump runs up to the firewall to a tee fitting under the hood seal. Check the line from the pump to there, you probably find a cracked hose or fitting, that is where I had a leak.



Sam

 

[gtwitch]

I never thought about that, but I had a similar issue with the vac line at the tee and another thing that is a dead give away is that the cruise control will not operate!! if the vac line comes loose at the tee.



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[Tuglife]

Sam & Gtwitch, thanks for the input... going to take your advice and look for any symptoms of this.

Nick

 

[AMink]

Would this also cause slow changes from dash to defrost? And dripping oil occasionally? I have a leaking steering box and thought that was leaving a snail trail when I back out of the driveway but the trails aren't evaporating like transmission fluid does.

 

[JR]

Loss of vacuum will cause loss of HVAC controls on the 2nd gens, I didn't think the third gens had a vacuum pump?

 

[Sticks]

Cruise is not also a given indicator, some of the 2nd gens were electric/ECM controlled. 4wd equipped vehicles though... No vacuum, no 4wd. That would be another place to check for broken vacuum lines.



Trucks this old, those plastic vacuum lines are very brittle. Does not take much to break them.

 

[Bill Stockard]

Loss of vacuum will cause loss of HVAC controls on the 2nd gens, I didn't think the third gens had a vacuum pump?

The 3rd gens don't have a mechanical vacuum pump like the earlier first and second gens; however, the early third gens with automatic transmissions do have an electric vacuum pump. Its only function is furnish vacuum to operate the cruise control servo.

Bill

 

[RonaldLarson]

I had no cruise, and it turned out to be that the vacuum feed hose from the pump area to the firewall was disconnected. There is a very small rubber fitting coming from the pump, where that hose should connect. Hard to see, but look carefully, it is in a nest of wiring , and small. The hose just pushes in to the fitting.