Mustang GT 2005 Autmatic/ 5R55S

[shadad]

Hi there

I was having strange issue with my car. out of sudden the trans was like acting strange and showing OD and check engine on the dashboard. i drove all the way home and next day it was fine. so when i drove it back to work the trans was acting strange again and the erros on the ODBII were saying all type of issue on the Trans like it need to be re built.

if i drive the car nicely like old grandpa, it will shift and drive very nice. if i push it hard like a sport car then the trans acting. I did took the car to a car shop where he said its a trans issue and i need to re built the whole thing. so i said OK! its my beloved car after all. even tho it was like just 80K since i built the trans as it fail previously before( it was way worse than this time).

They did re built the trans and just after i drove it out of the shop it act again !!! so some argument happen and i demanded a full refund as with full built nothing happen.

took it to another shop, he did the same thing and am on the process of pulling the plug . what could be the reason behind this? the 2nd shop says he said that this cant be trans issue. he checked all wires even. he suspect its a PCM / ECU !

what do you think guys? its a mustang GT 2005 Automatic with just 160000 KM

 

[86GT351]

What codes are you experiencing?

 

[07 Boss]

When you say rebuilt, could you provide more detail? If the bands and stuff are new I would look at the solenoid pack or the servo bores. Do you have any tuning capabilities? Upping the pressure may help.

 

[shadad]

What codes are you experiencing?

All kinda of Errors that says its a Trans issue. like the whole thing is busted. impossible lol :
P0740 (Torque convertor clutch )
P0743 Torque convertor clutch electrical
P0750 Shift Solenoid "A"
P0753 Shift Solenoid "A"
P0758 Shift Solenoid "B"

as i said, if i drive the car easy it shift nicely and the warning on the dashboard goes away and disappear. i dont think this is internal damage on the Trans itself or mechanical. otherwise the trans will act like this all the time even when am easy on it. 1st and 2nd shop replaced almost everything, Solenoid pack, clutch, valve assy(if this what it called) ,converter ,Pump.. you change all of that and the issue come back again? come on . the 1st shop checked this later and said it is now PCM/ ECU.

2nd shop did almost the same re built except he even replace the internals with heavy duty(must better) components that can withstand more beat. but after first drive it acted the same. so he now suspect its a PCM issue too. he said there is no other reasons as the Trans is built and he traced every wire to the PCM.

I have seen some crazy article that PCM could be suffering and cause some strange issues to specific part of the car. its just this is my first time seen this. i mean, if i drove the car easily it shift perfect and all errors goes after time. only when i get excited and punch it to the floor it acted like this.

so what do you think? ? i trusted s197forum more than Ford dealer itself. i mean, i could agree on the PCM shit thing. like what the hell? i already replaced almost everything on this level except that one. i just dont want to be ripped off for nothing mate.

 

[shadad]

When you say rebuilt, could you provide more detail? If the bands and stuff are new I would look at the solenoid pack or the servo bores. Do you have any tuning capabilities? Upping the pressure may help.

1st and 2nd shop replaced almost everything, Solenoid pack, clutch, valve assy(if this what it called) ,converter ,Pump. all new . 2nd shop even replaced some components with like more withstand and more heavy duty parts like sports type. kinds of the thing. i see on the 1st bill even things like Transmission kit. the bill itself is not cheap at all.
however, i never seen on both bills something related to the bands. both shops didnt do that? i dont think so. i will ask the 2nd shop on this part.
No Tuning ( Stock ). as i said only when i floor it hard it act like the trans itself is completely busted and all errors shows on the OBDII ( see my post above ).

 

[JC SSP]

On any basic auto tranny rebuild... clutch, bands, seals, gaskets, etc. are included. What's extra is torque converter (always highly recommended to replace) and electronics (solenoids, sensors, etc.)

You have 5 hard codes... One failure might be triggering the other (inter-related) faults.

I suggest you search for a local reputable tranny shop that's familiar with the electronics of 5R55S and see if they can find the issue.

I am curious, did tranny shop 1 and 2 give you any warranty?

 

[Cum Grano Salis]

So that’s 100,000 miles OD and a car 15+ years old, tranny still functions if babied. Was complete fluid force flush done and new filter change? Just didn’t pickup on if it was, read things too fast.

 

[shadad]

On any basic auto tranny rebuild... clutch, bands, seals, gaskets, etc. are included. What's extra is torque converter (always highly recommended to replace) and electronics (solenoids, sensors, etc.)

You have 5 hard codes... One failure might be triggering the other (inter-related) faults.

I suggest you search for a local reputable tranny shop that's familiar with the electronics of 5R55S and see if they can find the issue.

I am curious, did tranny shop 1 and 2 give you any warranty?

Thank you all.

It was the ECU. i have installed one from the junkyard and it run prefect! Trans was OKaaa. at less i almost get it for free + building sporty trans

but there is small issue, seems the 2nd hand ECU was installed on a a tuned car, i found the FAN running ON at low temperature and it run at high speed ! I cant let this happen otherwise it will put strain on the Fan. only when it reach specific temperature the low speed kick then the high as much i know.

also am getting like O2 sensors signal stuck lean bank 1 sensor 2 and bank2 sensor 1. Cods are p2270 and p2272. also if i rev the car hard it through like back fire and the engine riv is kinda high ( around 801 RPM). its 2005 GT Auto and i have screenshot on my phone from the OBD shows its like 713 at Idle. maybe the previous owner tune to cancel it?

none of these were appearing on the previous ECU. So, if i flash the stock OEM on the ford dealer will that solve all of that ?? will that return the Fan values to its stock numbers and maybe return the engine Rev Idle RPM?

sorry for bother you guys. but this is the last one

 

[Whpony96]

Definitely have the dealer Flash the ECU to stock. They can also correct the millage to match your cluster. (And verify the ECU is indeed good) Since the trans has been removed twice there is one thing you want to check. It's VERY easy to plug the front O2 harness plugs on the opposite side. Here is a pic of the correct harness routing.

 

[shadad]

Definitely have the dealer Flash the ECU to stock. They can also correct the millage to match your cluster. (And verify the ECU is indeed good) Since the trans has been removed twice there is one thing you want to check. It's VERY easy to plug the front O2 harness plugs on the opposite side. Here is a pic of the correct harness routing.

View attachment 85643

Hi Whpony96,
will visit them to flash the ECU. hopefully this will fix the temperature where the low and high speed fan kick on and also the engine Idle.