Clockspring?

I have an issue with my 96 TDI Passat. When I turn the wheel slightly (as in 15-20 degree angle) to the left, the car starts to choke and gasp like it isn't getting any fuel. When I turn it back to the right, it straightens up.

I recently replace the ECM since it was doing the choking/gasping thing all the time and the only way to fix it was to unhook the battery cables and let it sit for about 10 minutes. When everything was hooked back up, it could run for about a week without any issues. That part was diagnosed as a capacitance discharge issue and replacing the ECM was the only way to fix that.

Someone suggested that it might be the "clockspring", since in some cars they control/influence a lot of things. I don't even know if there is a clockspring so I thought it was worth asking.

You really need to scan the ECU with VCDS. If you don't have VCDS, someone may be able to come to you (or you to them) to scan the ECU. There's a sticky at the top of tdi101, "Vag-Com Locater" VCDS is the 'new' version of Vag-Com software.

Tony

Tony is right. You do have a clockspring, but it should have nothing to do with your symptoms.

Well, I have lost track of how many times it has been scanned and I get no error messages, at all, ever. Period. No matter who does the scanning or with what software version. Never have in the almost two years that the whole choking/gasping intermittent thing started.

Someone just thought it might be a clockspring since, apparently, an issue with the clockspring can cause some pretty weird things in other types of vehicles.

So, taking the clockspring thought out of the equation,here's description of the issue:

2 years ago, started intermittent choking/gasping. Not speed or RPM dependent, not a mechanical problem (replaced filters, lines, etc. to no avail). Checked/wrapped all the wiring we could see, did all the battery things we could find to do. Put in new alternator,new battery. Replaced all the relays. Progressively got worse over time until it became undriveable last spring. Replaced cracked vacuum lines.

Problem was still intermittent. Could drive it for about a week without an issue. Finally figured out we could make the problem go away when the battery cables were disconnected and we left it sit for about 15 minutes. That's when the capacitance discharge diagnosis came into play. Replaced the ECM with a rebuilt unit.

Now, the being-able-to-run-for-a-week part of the issue is gone but I can make the problem happen when I turn the wheel just slightly left of center. Sometimes it recovers when I turn the wheel back, sometimes it doesn't. Unhooking the battery now doesn't make the problem go away. I just have to let it sit.

It's unsafe to drive, since when the problem starts, I loose all forward motion and I have had some really scary near misses in a number of intersections.

I love this car. It does have 275K miles on it. I miss the almost 50 MPG I get in the worst way.

I am grasping at straws here. I think that this is likely a compound problem and we have fixed parts of the problem with everything we have done but we still have more to go.

This almost has to be another electrical issue doesn't it?

What's in the steering column or wheel that could be broken/shorting out/grounding out when the wheel turns?

Any thoughts/suggestions would be greatly appreciated.

Thanks!

Does it happen if the car is not moving? If it has to be moving how fast? Only on turns or will a lane change cause it?

I'm wondering about a fuel pickup issue in the tank though I would expect it to take a bit of time to happen. Notice any correlation with fuel level?

When you restart after sitting does it require much cranking?

What's in the steering column or wheel that could be broken/shorting out/grounding out when the wheel turns?

Click to expand...

The ignition switch. I'm betting down in your steering column there is a chafe through a wire or two that is causing the problem. That is where I'd start. You can look at the base of the steering column as well, but if you don't find anything there, just take it apart.

The steering colum is very easy to get apart, I do them all the time:

Disconnect the battery so the airbag won't deploy.
Remove the two allen screws, one on each side of the steering wheel underneath.
Lift the airbag off and unplug it, set it aside.
Using a 24mm socket, unscrew the large center nut in the middle of the steering wheel.
Using a marker, mark the alignment of the wheel to center shaft.
Use a screwdriver and remove the steering column cover, the screws are located on each side of the column, and are pointing at the floor. Remove the lower portion of this cover and set aside.
Grasphing the wheel, pull it towards you, but not too far since you need to unplug the clockspring.
After unplugging it, set it aside.
Using a screwdriver, remove the three bolts that hold the column switches on.
Unplug them as they come off. Don't worry about how they go back together, they are all different so it's impossible to mix them up.
Remove the upper cover half and expose all the wires that go down from there.
Look for any chafed wires.

We can make it happen when the car is stationary and the steering wheel gets turned 10-15 degrees to the left from center. (So, basically a lane change)

No correlation with fuel level.

Starts right up after it sits.

Thanks!

Then I guess I'd go with Abacus' suggestion though I don't know why letting it sit would make a difference.

Well, me either...Once we get this figured out (notice the optimist there), I will post the fix.

Thanks to everyone for the help.

Keep us posted on progress, and any questions or issues you may have.

Tony