7.3 Diesel help

[fabiodriven]

I posted this already on a Ford Powerstroke forum, but I figured it wouldn't hurt to post it here. Thanks guys-

I brought home my 99 F-350 dually pickup with a 6 speed and a 7.3 last week. I got it on the road two days ago and I am very pleased with it so far. I just have a couple of small issues and questions.

1- When I first got the truck, it used to kick up to a high idle when it was cold and make a sound from the exhaust that sounded like a jet taking off. It was really loud and I enjoyed it very much. Starting yesterday morning it doesn't kick up to the high idle anymore. Why is that?

2- My check engine light came on this morning, a full day after the high idle stopped working. I am going to attempt to put my OBD machine on it in a few minutes, but I am guessing it will not read a diesel. I'll see soon.

3- When I cruise down the road with my foot barely on the throttle just to maintain my speed I get a hissing sound and it feels like I have to keep my foot into it a little more to keep the truck going. Sometimes it even feels like the truck slows down a bit when the hissing starts. Once I get into the throttle a little and I'm under boost the hissing goes away.

[cattle-dog]

the high idle is for when its cold i genrally step on my throttle once and that sets the high idle before starting there is a plunger actuater thing on the throttle maybe it went and thats your code. or the temp sensor is bad and not telling it the engine is cold,make sure your vacume pump is working and has no leaks.

[UlsterATCFan]

Check the air flow meter

[fabiodriven]

What is an air flow meter?

I've got 3 codes-

P1670- EF Feedback Signal Not Detected

P1391- Glow Plug Circuit Low Input Bank No. 1(Right)

P1393- Glow Plug Circuit Low Input Bank No. 2 (Left)

[Mosh]

Ford TSB regarding low cold engine idle performance..Reflash PCM..Most carquests can do this for $100.

It only applies for non cruise control trucks...
----------------------------------------------------------------------------

Article No.
03-21-35

10/06/03

^ IDLE - IDLE SPEED TOO LOW WHEN COLD - VEHICLES WITHOUT CRUISE CONTROL AND WITH
7.3L DIESEL ENGINE

^ ENGINE - 7.3L DIESEL - IDLE SPEED TOO LOWWHEN COLD - VEHICLES WITHOUT CRUISE CONTROL

FORD:
1999 SUPER DUTY F SERIES, F-650

Article 99-18-2 is being republished in its entirety as part of a consolidated 7.3L diagnostic aid booklet.

ISSUE

On some vehicles not equipped with cruise control, the engine may idle at the normal engine RPM but lacks the cold engine idle kicker function to raise the engine RPM similar to those vehicles equipped with cruise control. This may be due to the Powertrain Control Module (PCM) strategy.

ACTION

------------------------------------------------------------------
On to the p1670 code..My factory data researches which is nationwide and private to ASE techs shows a slew of intermittent Camshaft sensor problems causing surging, stalling and DTC p1670..
That is a good guess without actually hands on diagnosisng the truck...

ANYTIME you are fighting driveability issues on newer vehicles...it is strongly suggested to reflash the PCM with any updates before attempting further diagnosis and parts replacement..
I would reflash it for the idle, and drop in a cam sensor before anything else.
Just my .02

[Mosh]

Also...
2 factory recalls are listed for failed cam sensors..Call ford, give them your VIN..They may fix it free.

[fabiodriven]

Thank you Rob. I will call them on that recall. My truck does have cruise control however.

[300rman]

that jet sound is basically a valve closing off to build some pressure and keep the exhaust from flowing freely to help the engine warm up faster. dad's does it in the winter as well.

[fabiodriven]

that jet sound is basically a valve closing off to build some pressure and keep the exhaust from flowing freely to help the engine warm up faster. dad's does it in the winter as well.

Somebody on the Powerstroke forum told me the same thing. The problem is the truck stopped doing it and I'm wondering why.

[fabiodriven]

I fixed the high idle. It won't go into high idle unless the parking brake is set. My switch on the parking brake wasn't always working so the truck doesn't know it's set.

[RapidRick]

Carry an extra cam sensor in the glove box. I do.

[Dirtcrasher]

Carry an extra cam sensor in the glove box. I do.

It's a sad day that THAT has to be done. Everything is junk, China owns us - I hate it all.

Good luck Fabio!

[fabiodriven]

Good luck Fabio!

Thank you Stevie boy!

[cattle-dog]

the problem is just that steve, the electronics and most parts are mostly made over seas. or a bordering country.

[VintageHondaKid]

we replaced a cam sensor on our 95 powerstroke and we were told that the international truck cam sensors are the best, the ford and aftermarket ones are junk. International builds these engines and their t444e is basically the same engine that they run in busses and big trucks.