Never again: engine wash 2006 Jetta - VW TDI forum and Audi TDI forum

Rig · #1 07-19-2011, 01:39 AM

The first time the engine conked out was when I went through some slush. I thought I had permanently damaged the engine, but it dried out after an hour and started and ran fine. I had heard about water getting into the intercooler, or something like that, and causing the engine to die.

But this time, it had the exact same problems when I rinsed some spilled oil off the engine with hot, soapy water. The engine did not start normally at the first crank, but took some pumping of the accelerator to get it to kick over--somewhat like on a very cold day. Then it ran a little rough, with the warning lights ("engine", "oil can", "glow coil") blinking. I opened the hood in the full sun and dried everything with a towel, and after an hour or so, it again started and ran normally, and the warning lights desisted.

So that's the last time I'm ever going to intentionally get water inside the engine compartment! What connections are suspect? Can I waterproof them in any way? I live where there is a LOT of water on the road in the fall, winter, and spring. And even sometimes in the summer.

buggy9 · #2 07-19-2011, 06:48 AM

VW plugs already have water seals but if you're spraying pressurized water everywhere I would think all bets are off.

If water gets into the engine cylinders it will hydrolock it and bend the rods. This would require an engine rebuild to fix. The only way it can get in normally is through the air filter.

Rig · #3 07-19-2011, 11:15 AM

I'm never again putting water in there intentionally, but what about the slush from the roads?

What connections would cause the malfunctions I described?

Rig · #4 08-16-2011, 02:51 AM

OK. It happened again--drove in some hard rain, and the engine died. I opened the hood and looked for wet sensor connections and saw none. I wiggled all the sensor connections I could find and then went back in and started the engine and drove away normally.

What sensor would likely be doing this?

50mpg · #5 08-16-2011, 05:05 AM

Do you have a splash pan in place?

Rig · #6 08-16-2011, 11:28 AM

Yes, the splash pan is in place. It is a little bent from winter's snow and ice. The splash guard on the right wheel is missing some screws, and there's a little gap.

The only water I saw when I opened the hood was near the battery box and the fuse box, but not much.

chittychittybangbang · #7 08-16-2011, 02:42 PM

The engine bay should stay relatively dry, even in rain. There are some gaps along the edges of the hood but I think there are gaskets there.

On a dry day, try spraying some water around the engine compartment and seeing which area causes the problem. This will narrow it down and you can go from there.

Check the area under the windshield since that's where the ECU lives.

Also do a boost leak test to make sure all the hoses are tight.

Rig · #8 08-17-2011, 09:54 PM

I'm scared to squirt water in there!

Maybe I'd do it if the sun were shining brightly, and I didn't have to go anywhere.

I like my old diesel tractor--if it has fuel, it runs. But it doesn't get 45 mpg on the highway either!

MTB_TDI · #9 01-22-2012, 03:56 PM

I have had the same issue. In fact, yesterday I couldn't even start the car at all for a while. That had never happened. I ran VAG-COM and got the CEL: P0321, Engine speed sensor, signal unplausable or something of the such.

TDIClub.com says that there could be a short under the battery to the ground. So I am going to chase the wires from the sensor. I will post my results.

Last fall when I replaced my RMS, which has the speed sensor connected to it, I put in some dielectric grease in the connection. That didn't solve it.