Hey guys,

Basically, the transmission in my TF Magna has been giving me trouble.

1. If you are driving around 80-100km/h and let go of the accelerator, the transmission shifts into 1st or 2nd gear, you can tell because the whole car jolts and the engine revs right up.

2. When cold, it feels like it takes off in too high gear because when you accelerate it feels like it is in 3rd or 4th, takes off like it is down on power, then it will be fine.

I took it to a transmission specialist today and he said to try change the ECU because it is common? And he said do not get a second hand ECU because it will more then likely do the same thing.

Has anyone else had a similar problem, I don't want to buy a ECU if that isn't the problem.

Also, if I was to replace the ECU, would I need to change the key? ignition barrel? etc, or just remove old ECU and fit the new ECU.

The guy at the transmission place said that the ECU is on top of the transmission tunnel? Is this true, and if so, what is the easiest way to get to it?

Sorry for all the questions but thanks to anyone that can help with this.

Cheers,
Ben

For starters this is a load of BS......

Poss may be a leaking heater core, this can play havoc with the auto, get this checked

For starters this is a load of BS......

Poss may be a leaking heater core, this can play havoc with the auto, get this checked

I haven't had a problem with losing coolant or anything like that and the window doesn't fog up, etc. Just the 2 transmission problems as I have described. If you don't think it is the ECU then maybe I should get a second opinion? But that's what this is actually, was hoping you guys would have a better idea.

Another problem is every now and then the speedo stops working for 2 seconds (travelling at 100km/h (example) it drops to 0km/h then goes straight back up to 100km/h), could all this be affected by the same thing or could there be multiple problems?

I haven't had a problem with losing coolant or anything like that and the window doesn't fog up, etc. Just the 2 transmission problems as I have described. If you don't think it is the ECU then maybe I should get a second opinion? But that's what this is actually, was hoping you guys would have a better idea.

Another problem is every now and then the speedo stops working for 2 seconds (travelling at 100km/h (example) it drops to 0km/h then goes straight back up to 100km/h), could all this be affected by the same thing or could there be multiple problems?

You won't notice the loss of coolant or you'd have green carpet by now :P

Grab a torch, get into the passenger footwell, pull up a bit of the far right carpet (enough so you have access to the sound deadening underlay on the bottom) and if it's damp you've got a heater core leak. What happens is the heater core leaks in all 3rd gens and the first thing it wrecks havoc with is the ECU and A/T ECU (both are brilliantly located directly under the HVAC, where the the heater core resides.

From here, the options are:

Get Mal (MadMagna) to repair it,
Do it yourself - Dash out/in job, takes a few days if you have NFI what you're doing
Live with coolant slowly leaking into the cabin, erratic driving habits of the vehicle, perhaps even the complete seizure of the ECU.

You won't notice the loss of coolant or you'd have green carpet by now :P

Grab a torch, get into the passenger footwell, pull up a bit of the far right carpet (enough so you have access to the sound deadening underlay on the bottom) and if it's damp you've got a heater core leak. What happens is the heater core leaks in all 3rd gens and the first thing it wrecks havoc with is the ECU and A/T ECU (both are brilliantly located directly under the HVAC, where the the heater core resides.

From here, the options are:

Get Mal (MadMagna) to repair it,
Do it yourself - Dash out/in job, takes a few days if you have NFI what you're doing
Live with coolant slowly leaking into the cabin, erratic driving habits of the vehicle, perhaps even the complete seizure of the ECU.

I will have a look tomorrow and let you know. Thanks for the help guys, sorry if it seemed like I was having a go at you Madmagna, I appreciate you helping. I was just saying what I was told the problem was. They didn't even road test the car, they just went by what I told them.

I will have a look tomorrow and let you know. Thanks for the help guys, sorry if it seemed like I was having a go at you Madmagna, I appreciate you helping. I was just saying what I was told the problem was. They didn't even road test the car, they just went by what I told them.

You'll find you'll get a better result from asking a bunch of forum enthusiasts versus an auto electrician or a mechanic (with some exceptions).

You'll find you'll get a better result from asking a bunch of forum enthusiasts versus an auto electrician or a mechanic (with some exceptions).

Yeah I have fixed a few problems I have had just by looking through this forum haha.

By the way I just went out to the car and had a quick look. I pulled the carpet back on the passenger side so I could see the sound deadening and underlay. There is no dampness and I can't smell anything. I will be using the car for all this week so I will keep an eye on it to see if anything develops.

Well if you do need a tcu I have one. The 4cyl still ran a separate tcu and ecu

Checking for leaking coolant will result in pulling the carpet up, and then pulling the MLV (Mass Loaded Vinyl) closer to the firewall and the insulation attached to it up. Its not normally noticeable to start with so check very carefully.

The seals on my heater core has just gone and it has leaked onto my ECU and caused me to have many issues when the car warms to operating temp. The Heater Core isnt directly above the ECU but its close.

As for the ECU if you follow the transmission tunnel to the firewall you will find it there, if you want to check the condition of it pull the carpet back on both sides of the car and get in there with a torch.

I can't guarantee this will work but it is one thing you might be able to try, to reset the ecu.
Procedure according to this chart:
http://desmond.imageshack.us/Himg14/scaled.php?server=14&filename=magnatransshift.jpg&res=landing