2001 Mustang GT automatic trans 2-3 shift problem

[Mustang5OH]

My son's 2001 Mustang GT automatic trans (4r70w) recently started acting up. Had an issue with what the shop thought was the fuel pump (erratic idle, stalling, pressure fluctuating) so a new fuel pump was installed. Upon starting it up, the car ran perfect so since I was at the shop, they had me test drive it. Made it onto the street and when the transmission shifted from 2nd to 3rd gear, it felt like someone mashed the brakes and was trying to power brake the car. you could feel the engine trying to push the car but it was bogging down as if the brakes were locked up. When I let off the accelerator and came to a stop, I could take off again like nothing ever happened until the 2-3 shift and it did the same thing. Prior to driving, the shop put a scanner on because they didn't realize the converters had been removed which throws a code. They told me they saw codes for the EGR (also removed), O2 sensors (due to converters), a security code and something about a shift solenoid code. They cleared all of the codes prior to driving and after driving and noticing the shifting problem, they tried the scanner but no codes were present. Not sure if it has anything to do with it but, the gear selector inside the car is also hard to move. Took it to another shop for transmission diagnosis, and it ran the same as before the fuel pump was replaced. When I turned the key on to the run position, it sounds like a relay under the hood clicking along with the fuel pump cycling in correspondence with the clicking under the hood. We're thinking the Constant Control Relay Module (CCRM) may be the culprit with the fuel pump and running issue since the fuel ump and filter have both been replaced. Has anyone had any experiences like this with their (4r70w)? I know the CCRM controls the cooling fan, A/C clutch, fuel pump power module, and provides power to the PCM, but does it also control other aspects such as the transmission? Thank you!

 

[07GtS197]

What code is it throwing for the shift solenoid? It sounds like that’s the issue.

 

[Mustang5OH]

When he cleared the codes after the fuel pup R&R, he did so without thinking because there were no reported issues with the transmission. All he could recall was it was a shift solenoid. There have not been any codes since even after driving and noticing the issue. From what I can tell, if it was a broken hub in the transmission, it would act as if it were in neutral.

 

[07GtS197]

I think it’s an electrical fault not a hard part fault in the trans. It will still throw codes even if the cel is off.

 

[Mustang5OH]

Well, this sucks! Once it was towed to the transmission shop, they couldn't keep it running as it was like it was running out of gas. This is what it was doing before the fuel pump was replaced but was running fine afterward. When the ignition key was turned to the run position, you could hear the fuel pump cycle on/off/on/off/on/off each for about 2 seconds. There was also the same clicking under the hood which was not from any of the relays in the power dist box and if you were on the passenger side, it was not in the area of the CCRM which was replaced. Yet, it sounded like it was coming from the area of the bellhousing/firewall area. after doing some checking of the fuel pump driver module and shut off switch (both good), all cycling stopped and there is not even 1# of fuel pressure and won't start. Anyone have any ideas? The shop owner checked the harness at the shutoff which has power. he was going to check the harness at the pump next but haven't heard back yet. We're all puzzled.

 

[07GtS197]

Pull the steering column shroud and check the ignition switch. It might be separating. Or put the key in run and give the underside of the steering column shroud some technical taps. It sounds like a bad ignition switch.

 

[Mustang5OH]

We’ll give it a try. Thanks!