I've got a 2002 X-Type. In the last two rainstorms that I drove in, I was running 65-70 MPH at around 2200 RPM, then out of nowhere, the engine revs up to around 3200 RPM. Engine light comes on, transmission fault light comes on. Car dried out, engine running normal. After the first occurrence, I took it into my local transmission shop, they couldn't find anything wrong with the transmission, no transmission codes faults, and it now is acting normal.
The second rainstorm, same thing, engine RPMs bump from 2200 to 3200. Again, when the car dries out, back to normal.

It's almost as if the car is downshifting out of overdrive. Lots of ideas in my head, but wanted to pick some brains out there. Could it be related to the traction control? Is there a sensor that can short out when it gets wet?

Any ideas would be helpful and appreciated.

 

jehumbert, first off, welcome to the Forums. Lots of good information here and lots of people willing to help. But, we do ask a small favor from you. Please stop by the New Member Section and tell us a little bit about yourself and your car. We pride ourselves in being a better car group and as part of this, we like to get to know one another. This will also give you a chance to meet those that make this place what it is.

As for your problem, it is kinda sounding like your TCM (tranny computer) is getting a littel bit of water into the plug and it is causing it to see things that are not necessarily true. The big qustion that I have is whether it is the tranny downshifting or if the torque converter is dropping out. The next time this happens, keep an eye on the tach (don't loose focus of the road) and let off the gas (do not step on the brake). Do the RPMs drop significantly (more than 200 RPM) or do they remain fairly constant (dropping slightly with the speed of the car)? If the RPMs drop, then the issue is with the torque converter or its wiring. If the RPMs remain fairly constant, then the tranny downshifted.

Doing some number crunching, it is most likely the torque convert coming undone. But, I also think that it is possible that it is downshifting from 5th to 4th gear too (my car runs about 2500-2600 RPM at 70 MPH) which would then put the RPMs up in the 3200 RPM range if it downshifted to 4th.

One thing that you can do is to feel the floor carpet in the driver's footwell area (for your car, RHD cars this would be the passenger footwell area). If this is getting wet (beyond what may be on your shoes), then this would lead back to water coming in through the wheel well and on to the computer.

One last thing that you may want to consider doing is getting the codes read for your car. It may be triggering something and that may help pinpoint where the problem is.

 

Hello, and thanks for the response. When I had the car in the transmission shop, they read the codes and did not find anything specific to the transmission. I have a code reader, and I will take a look and post the codes it has, here.

I can't remember what the RPMs did last time it occurred, but I will watch the next time. I do know that I have been getting water in the passenger's footwell area, my wife noticed it one other time. But that particular instance, she had no trouble with the car, she just noticed the water on the floor mat after a large rainstorm. The car was parked at her office all day.

I will keep an eye out and try and describe what I see next time it occurs.

I will post in the new members area as soon as I can.

Thanks

 

A common source of water that causes your sort of problem with the TCM as described by Thermo, is a blocked drainage system from the pollen filter plenum chamber.

The proper way to access that is by removing both windscreen wipers and the plastic fixings across the front of the plastic panel in front of the windscreen. Lift the panel away - it may be held by double sided sticky tape to the base of the windscreen plus its tongue and groove arrangement, again, across the width of the screen.

The pollen filter just pulls out of its housing and a new one should be installed, noting the airflow direction arrow. But while you're in there, check out the drains and clean out the the whole area that will almost certainly be a bit of a midden to use an old English expression!

Re-assembly is just a reversal of the strip-down

 

I will take a look at that, also. Thanks!