Smoke, smelly burning, and a mess under the car

While driving across country Labor Day weekend, the transmission plug fell off of my car (2001 Saab 9-5). There was a lot of smoke, the exclamation point indicator on the dash came on, and I pulled over right away only to watch a huge puddle forming under my car along a strip of the I-80 in Nebraska. A very nice tow truck driver took me to a parts store, put in the new plug, and replaced my transmission fluid.

Since then though, including periodically during the remainder of my cross-country trip, I occasionally get a small amount of smoke coming from under the hood and a pretty bad burning smell. Also when I had the oil changed, the guy in the pit said it was pretty ugly under my car.

[I also know I have a small oil leak but nothing major]

I rarely ever drive the car (for two months I only ever moved it across the street every two weeks for street cleaning) but when I do drive the car I would like it not smell like I am barbecuing balloons filled with motor oil.

So I’m assuming that my problem stems from all the transmission fluid that got all over everything under my car. How do I get this stuff off? Is this something for an undercarriage wash, or engine steam clean? How much should I expect to pay for this? And any recommendations for this service in Oakland, CA?


It may, but there might also be a mitigating factor. Did you recheck the tranny fluid level after it was refilled? Much of the fluid resides in the hydraulic system and the torque converter, which is why the manual suggests checking it with the motor running. My manual even suggests “running it through the gears” before checking.

Also, that small oil leak is probably contributing. If you have oil getting pushed past the valvecover gaskets it can migrate to the hot exhaust manifold or header pipe (the one bolted to the manifold) and smoke when the system is hot. And it will also make a mess of the engine’s underside. Oil getting pushed past the gaskets can be caused by a plugged Positive Crankcase Ventilation (PCV) valve or system, so you’ll want to ceck that out.

An option woud be to have the underside washed, buy a UV (blacklight) sensitive dye, and use that to find out exactly where the oil leak is originating. That’d be the best first step toward eliminating it.

I’m curious: do you frequent a quickie lube place? They’ve been know to remove tranny drain plugs to try to convince the owners to get a flush when they come in for a simple oil change. Did this happen to you? I find it unlikely that the original tranny plug would fall out on its own.


  • Yes, I did check the transmission fluid after refilling.

  • I’ve never heard of the UV sensitive dye- I will research that as I am quite curious about from where exactly the oil is leaking.

  • I’ve only had the car since June, so I’ve only had the oil changed twice. I do know that the guy from whom I bought the car had recently replaced the transmission with one that was rebuilt.

Wouldn’t removing the plug cause all the fluid to come out immediately? I don’t think that the two different places at which I’ve had my oil changed were up to shenanigans as they didn’t try to up sell any other services.

They don’t actually remove the plug completely, their trick is to loosen the plug enough to get a few drops out onto a clean white cloth, whereupon the compare it to a drop of new fluid and say you need a flush. The stuff dripping out from the bottom of the pan will ALWAYS look dirty when compared to a drop of new stuff on a clean white cloth. It’s a scam. But if they forget to tighten the plug properly, it can fall out.

However, since it’s had the tranny replaced, anything is possible.