Wierd throttle issue.

[Slamaxe]

I tried searching but after half an hour I gave up.

I'm new to the 7.3 PS so some things just don't compute for me. For instance, If I don't set the parking brake when I start the car, the throttle doesn't work. I can start the truck just fine, it idles fine but when I step on the throttle, the pedal depresses but the engine just idles and the transmission won't engage.

After it runs for a minute or two it generally works fine OR if I shut 'er down, set the parking brake and restart, it will run fine. Now does anyone have any ideas about this? If I was running from zombies I'd be stuck...

Ron

[cchase]

that is one of the odds things i have heard... i dont even know where to start

[Banshee34]

Sounds like gremlins to me! Sorry I had to.

One of the great techs should be along shortly!

[95dieselsmoke]

this is wierd. could a faulty TPS do this?

[Slamaxe]

Here is more of the story. The vehicle has a Ford idle controller...

What IZZIT?

In order to get to the back of the engine I have to disconnect the unit to remove the doghouse over the rear of the engine (E350 4x4 van). Yesterday I removed the unit to R&R the glow plug relay. Today the issue appeared again. This does not happen every time I start the engine but it seems to be only when it is cold. Once warm all is (knock on wood) good.

When it is happening I get a "check engine" light each time I press the throttle which suggests the TPS is working or at least signaling. I'm wondering if something in the Ford idle controller is disconnecting the throttle until things warm up. I don't know enough about the device to be able to figure that part out.

There is no chip on the computer, yet.

I thought about the CPS but there it never hesitates, stops or behaves like I expect a bad CPS to behave.

As an aside... When I removed the bad glow plug relay I took the time to grind it open to see what had gone wrong as the solenoid seemed to work but no current was flowing to the glow plugs. Apparently some Neanderthal, at some point decided to torque the power leads down nice and tight. SO tight that he sucked the contact right through the phenolic that makes up the relay case and that pulled the face of the contact away from the contact plate. There were microscopic cracks but nothing really obvious from the outside. The thing worked fine for awhile and then....

Anyway....

Slam

[Slamaxe]

Sort of an update.

The problem seems to be related to engine temperature. Yesterday I drove the 35 miles out to Spokane, Wa and parked... cold and rainy about 38f. After about 5 hours it was time to go and I got in the engine felt dead cold but not overnight cold. It started up and no throttle... in about 15 seconds the throttle was back.

Last night it got down to about 32-34f and the engine got overnight cold. It started up but took almost a minute to give me throttle. This is consistent with when I was in Wyoming and it was 17f overnight and took around a minute to release control to me.

If the car is warm the throttle works immediately.

That's my cactus and I'm sticking to it.

Slam

[outlawdiesel]

It sounds like moisture in wires or plug in's.this is a shot in the dark ?

[Dave]

Originally Posted by Slamaxe

Sort of an update.

The problem seems to be related to engine temperature. Yesterday I drove the 35 miles out to Spokane, Wa and parked... cold and rainy about 38f. After about 5 hours it was time to go and I got in the engine felt dead cold but not overnight cold. It started up and no throttle... in about 15 seconds the throttle was back.

Last night it got down to about 32-34f and the engine got overnight cold. It started up but took almost a minute to give me throttle. This is consistent with when I was in Wyoming and it was 17f overnight and took around a minute to release control to me.

If the car is warm the throttle works immediately.

That's my cactus and I'm sticking to it.

Slam

What are you running for oil? 15w40 is quite thick at those temps. It takes a bit for the oil to warm enough to properly fire the injectors.

It also sounds like the Aux Idle controller may be causing issues for you as well

[Slamaxe]

Thanks! I plan to check the connections today. It's not an enormous PITA but it is annoying. If it's some sort of function I'm OK with it. If it's a part going South I'm not OK with it.

I use Rotella 15x40.

I'll check the idle controller today. I have the machine off, cooling down, I plan to disconnect the device and see what happens. It starts and runs fine without the controller plugged in as happens when I have the engine cover off during work. Never tried it when it starts to cool down.

This thing was first sold in Alaska. It has the block heater as well as battery heaters. They might have added some other safety we don't see here where it seldom drops below 0f.

Slam

[Slamaxe]

Just an update.

Problem solved. It's programmed into the computer. I got an email from a Ford guy who said that in VERY cold climes they program in a throttle disconnect until the engine heats to a certain point. The vehicle was built for Alaska.

As confirmation, I installed a TS performance chip (I know... don't hammer me with DP is better I don't need more than what I got) and the issue disappeared on position one (50 hp) and all the other positions.

FWIW I like the TS chip so far. It is smooth and works as advertised. On the high power setting the thing smokes like a locomotive. Transmission shifts have been smooth and on time.

I guess that is all I can add to this thread.

Slam