urquattro20Vt

Guys-
Ok so recently I had an oil hose split (car is a '91 Turbo) and it dumped several quarts of oil - first onto the passenger side heat exchanger before hitting the ground. I've replaced the hose and refilled the oil. No more leak. I wiped down but did not clean the HE prior to start up - so it will take some time to burn off the remaining residue.

Getting to my question - while idling in the garage for a while it definitely smoked. When I turned the heat on quite a bit of smoke came out of the vents. Smoke also came out of the cowl area (I had the drip tray removed to inspect operation of the mixing servos). When I turned the A/C on the smoke pretty much went away - or was greatly reduced.

Does this smoke getting into the HVAC mean I have ripped HVAC tubing somewhere? Or just a natural consequence of lots of oil dripping onto the HE?

Thanks guys-

Brandon
'00 Audi S4 - heavily modified DD
'91 911 Turbo

CraigC

You may have gotten oil into your heater boxes or the most likely reason for the oil smoke is a tear in the fabric hose that connects the heater box to the interior hvac system. See if there are any tears, holes or lose connections between the heater box connection and the Orange fabric hose

Dreamstate

I had the same issue on my car but with power steering fluid. The hose between the PS reservoir and PS pump began to leak and the fluid was mostly finding its way to the ground via the exterior of the heat exchangers. However when removing them during an engine drop a couple months ago and found a thin pool of power steering fluid inside the right side exchanger. It appears that it had been creeping in through the seam where the header was meeting the exchanger tins or between the two halves of the heat exchanger.

urquattro20Vt

Thanks guys. Follow up question.

Not only was smoke coming out of the vents when the heat was on - it was coming from under the cowl - in front of windshield by the mixing servos. I've heard of a flex hose in the passenger (only?) footwell area tearing. I cannot find a procedure for getting to it to inspect tho - any info appreciated.

The smoke is gone now that I've gotten a good drive in - but one of these days I do want to clean the inside of the HE's out - I bet there is decent amount of oily goop in there after 26 years.

Brandon
'00 Audi S4 highly modified DD
'91 911 Turbo

Mongo84

Happened with mine, small amount of oil dripping onto the heat exchangers worked its way up from a tear in the hose, came through the vents and the dash. Took the dash out thinking it was electrical but that wasn't the problem.