Hi everyone!

I’m currently replacing my automatic transmission in my Audi A4 1998 2.8q and I have some issues. I got a great deal on an S4 transmission that had low mileage at low cost. Now that I have busted my budget just to install it. My mechanic told me that the transmission was the same but the electronic wasn’t. The car seems to work but after 100m the car fall in LIMP MODE and is stuck in second gear.
This is the only code that I am getting:
- 6182 Trans Input Speed Sensor (iss)

So my mechanic told me that the cables from my module do not communicate with the same parts in the transmission and that is my problem.
My question is, do I need to get a Trans Control Module from an S4 and all the wire and everything will work properly? Do I have anything else to think about? And does my Engine ECU will recognise my TCM if I change it for an S4 TCM?

Thanks for your help

 

s4 tcm would be needed but its also a waste using an s4 tranny without the rest of the s4 driveline. you should get the rear diff also because the ratios are different. Im not sure if the auto trans in the s4 is even different from the a4 one? or if the ECU can communicate with an s4 TCM without reworking it in VAG com

 

The S4 tranny is physicaly the same. Its the same thing with same ratio that my 2.8 only the wiring is different so my communication with the tcm is all fu**-up

How the ECU is communicating with the TCM? This is direct wire to the module?

 

Was there ever a resolution to your problem? I am having a very similar problem now, where I was not given the transmission I believed I was buying. So I have a DRD that came out of my 98 A4 and a EZZ was put in and now I am dealing with the limp mode after 3rd gear issue. Did swapping the TCU do the job? Did it have to be reprogramed? The car is a 1998 A4 Avant 2.8 if that is relevant.

 

After posting this in 2012 I finally tried an S4 TCM in my car to be able to speak with the transmission. that didnt work out for me as the TCM would not speak to the ECU anymore. I finally changed the transmission again this time with the right code. Maybe some experts would be able to reprogram the ECU to speak with the right TCM but at the time even the dealer wasnt able to do it. my recommendation is to remove the trans, sell it, then buy the right one.

 

Thanks for the response. That is rather disheartening news. I am sending the car to a Audi and VW specific repair/tuning shop that seamed to think they might be able to make it work. I am hopeful that they can. If not I will probably just sell the car for someone else to deal with. I will post whatever the final out come is.

 

A DRD is a 2.727 final drive ratios transmission with a PNP switch E17 Hydraulic control, while the EZZ is a 3.09:1 rear foglight switch E18-2 hydraulic control transmission. They are not the same ratio, that's probably why it goes into limp mode, or the same control types, the e17 has an inductive speed sensor in the valve body, the e18 has a hall effect speed sensor. Both are located on the top of the valve body(need to remove the VB to get at them). You need a TCU from a EZZ car, or at least an E18 hydraulic controlled transmission. Don't think you can recode your existing one to work with a different speed sensor. Don't know what the difference is between park neutral position (PNP), and rear fog light control is either