7.3 Stalling issue

[redthies]

The 97 is apparently stalling when Cristian is (for some reason) downshifting D-2-1. (I have suggested he does not drive it this way to keep his trans healthy, brakes being far cheaper than a trans). But I mention the downshifting in case it is relevant. The cam position sensor was replaced under warranty (recall) in Dec, and his symptoms sounded the same, so the Ford dealer in Vanderhoof (middle of nowhere on way to Alaska) stepped up to the plate and did a lightning fast cps replacement again, at no charge! Great service, but the stalling started again shortly after. The service advisor suggested that the camshaft can shift forwards or back a bit, and get out of contact with the sensor. Any of the PSD crowd here heard of this? Any other thoughts?

 

[Martyn]

A Google search for "7.3 stalling" comes up with a laundry list of potential issues.

 

[Darwin]

I am no PSD expert, but is it possible the fuel pump is failing or they are not getting adequate fuel pressure to the injectors?

 

[bulrid8]

Possibly bad IPR. Any codes?

Sent from my ADR6400L using Tapatalk 2

 

[redthies]

No codes. It starts again immediately, and idles fine so I don't think it's fuel pump or pressure. IPR? Injection pump relay? Too many acronyms is one of the only things I hate about PSDs.

 

[Martyn]

The IPR is the Injection Pressure Regulator, it controls the oil pressure to the injectors.

Does this vehicle have a performance chip in it?

Try this post on the Ford-Trucks Forum to see if it gives you any answers.

Sometimes it's difficult to get the codes off this vehicle, you may need to go to a diesel specialist or the dealer to get a full scan.

 

[Scrapdaddy]

On my 95, the cam sensor would get hot and fail, then cool down and start again. This took awhile, overnight at the dealers. It didn't throw a code until the third failure.

 

[redthies]

No chip, it went to the dealer on friday. They replaced the cps for free. It's the second in the past six months. First one replaced was the original from 97 replaced under recall. It is starting fine, idling fine and running fine. It just shuts off occasionally when he stops for a light, or almost comes to a stop.

The motor has 280k on it, but I've never heard of what the dealer is saying about the cam moving forward/rearward in the block.

 

[XRrider]

I'd assume a cam can walk in a diesel as its not got the distibutor gear applying a constant directional force to the cam like a gas engine. However it would seem unlikely it could walk far enough to lose "contact" wih the cps? I never had an issue while slowing down with my '96 psd, mine would die at a constant highway speed and refire again before stopping.

 

[speedyone]

Does it also run rough in reverse? I had a similar issue with my 1997 F350 7.3. It ran fine except when I manually shifted the trans into first gear or into reverse. It would run rough and stall. I found there is an issue with the original transmission filters that came on the trucks. There is enough space for them to come loose from their mounting position and float. The newer filters were redesigned with a hump to keep this from occurring. There is a technical service bulletin from Ford that explains the issue. When I removed the pan from the trans my filter was in fact not attached and fell out with the pan. I did confirm the redesign of the filter and installed the new one and problem solved.

Edit: Here is the info from Ford on the issue:

Stall when engaging transmission (automatic, usually manual low or reverse):

Torque Converter Clutch.
This may be caused by the TCC being engaged at idle. On trucks built before 9-20-95 the correction is a new transmission front pump and/or torque converter. On trucks built after the above date, it could be cause by a loose transmission filter. In this case, install a flat magnetic strip (from a Tempo ATX or Ranger A4LD transmission) in the trans pan below the filter pick up to retain the filter in place or use an updated filter from Ford that has bumps cast into the plastic to help it stay in place.

 

[surlydiesel]

I was going to go with torque converter after the CPS was ruled out.

-jorge

 

[redthies]

Thanks for the input guys. They just serviced the trans, and I think all was ok. I'll ask him when they get off the ferry in Alaska, or maybe I'll call our mechanic who helped with all the services and see which filter they put in the trans.