OK, so I just got a brand new Jasper engine (4.6) put in my 2000 expy. New steering pump pulley too.

Runs great, but I noticed that when I turn the wheel rapidly the engine dies. Just like someone turned off the key. It does it more when I'm turning left, but sometimes it does it when I'm turning right.

If I turn the wheel slowly it won't do it. Or if I'm on the gas. But If I"m trying to park, or I'm at a stop light and I got to do a u turn, forget it. It dies.

I can be sitting still and crank the wheel and it dies. No check engine light, no low power steering fluid, everything else seems fine.

 

Either the steering sensor is broken or not hooked up, or your IAC valve needs to be cleaned or replaced. Turning the steering places additional load on the engine and can cause stalling. To offset this effect, there is a sensor that tells the ECM to raise the idle to compensate. That doesn't seem to be happening with your vehicle.

 

Since the engine was just replaced, I'm hoping its the sensor. How would I check or change that?

 

Since expeditions have variable assist steering, the sensor is mounted to the steering column under the dash instead of being in the engine compartment. Look under the dash for a wheel with slots in it all around. That's the sensor wheel that passes through the sensor as you spin the steering wheel.

I'd be more inclined to think the IAC valve is just being a bit sticky, rather than think the sensor is all of the sudden no good. Of course it's possible that some wiring was damaged during the engine swap.

 

There have been some posts where a worn wire was found on the left side of the steering column near the turn signal stalk causing the same problem.

 

Well, I haven't had time to really look at it since the wife has it most of the time, but I sat in it just and and did a test. I started off with the wheels straight and cranked it to the right as fast as I could, twice. No stalling.

Then, I did the same thing, only to the left, and it stall both times, in almost the same spot, like clockwork. So it has to be a switch or a wire.....

 

You might want to take the plastic cover off just below the steering wheek and give the wires a close inspection. It's only 3 or 4 phillips head or torx screws holding it on, about 5 minutes of work.

 

I will do this, but I just had a thought. My horn and cruise buttons on the steering wheel don't work. I've been told there is a small device I have to replace that resides under the steering wheel. Could that also be starting to cause this?

 

While you are in there you might check all of your wires using a multimeter, for juice to the switches, the problems might be related.

 

Wilco.

Will report back.

 

That part is called the clockspring and normally I would say that it should not be related to the stalling problem. However, it's possible the clockspring is just fine and you have broken or pinched wires in the column that is effecting all of the problems. The three problems (horn, cruise, stalling) all seem to be tied to the steering column. Like Moto Mel said, it's time for a visual inspection.

 

OK, I just now had a chance to look at it, but not before it got worse.

Now, it's starting to just stall randomly, even driving down the road.

I have actually torn the sterring colomn apart because it's dark, but I noticed a very loud, pronounced "clunk" the second the engine dies.

Got a video. I made my wife turn the steering wheel slowly and it the clunk happens around the 49 second mark. You can't miss it. It's even louder and more pronounced when you hear it in person, the camera does not do it justice.

YouTube - Loud Clunk

 

I heard the clunk and it is loud. I have never heard anything like that that wasn't a mechanical failure. Your engine sounds good otherwise.

 

Try doing the same thing again as in the video to see if you can repeat the clunk. But this time watch the belt tensioner pulley to see if it jumps when you hear the clunk. If it jumps, the PS pump could be locking up on you.

 

Really? ****, the mechanic put in a new....either PS pump or PS pump pulley when they replaced the engine...I'll have to double check which.