Ok... Ive posted once or twice about this problem but had no come back so I will try to explain it in a bit more detail! When I first fire up my 91 uk tt and drive off while cold the gears go 1-2 maybe to 3rd sometimes? and not 4th but when shes hot I have to boot it hard before it will kick into 4th then it works fine driving normal but when I boot it through the gears it goes 1-2 as normal then its goes 2-4 soon as it hits 4th it kicks back into 3rd strait away then winds up through 3rd then into 4th and will do this all day long this has been going on for nearly a year. I cant get the diagnostic test to work so have no idea of fault codes??? I have done a oil chance a couple weeks ago which looked like this,

oil was brown in colour maybe not changed for a few years??? but no obvious signs of disintegration, spotless infact! which was nice to see!

Colour of oil pic,

 

Does the box have a separate ECU? which could be screwed??

If anyone can help with this that would be great? Cheers...

Anyone out there that knows about problems like this??? Anyoneeeeeeeeeeee??

I will ask if my brother will talk to you if you like? He is retired but did nothing but autos. Yes/no?

what happens if you turn overdrive of? Will it go through 1, 2,3 then lockup?

 

Also "4th" is overdrive, and it is a bit weird, are you sure its actually going into "4th" or lockup? and then down into 3rd?

 

Autobox has its own ecu, have you tried resetting? Would need to be a battery of for over night or however long it takes to clear any fault codes or issues it has.

 

When cold these autoboxes dont like to change, especially if you have an aftermarket oil cooler on. I know mine doesnt, lockup can take a few miles to be available. Obivously they thrive on the oil being warm, with an aftermarket cooler it takes longer to warm up!

I will ask if my brother will talk to you if you like? He is retired but did nothing but autos. Yes/no?

That would be great... YES!!! PM me if you need to give numbers?? cheers mate :hyper:

what happens if you turn overdrive of? Will it go through 1, 2,3 then lockup?

 

Also "4th" is overdrive, and it is a bit weird, are you sure its actually going into "4th" or lockup? and then down into 3rd?

 

Autobox has its own ecu, have you tried resetting? Would need to be a battery of for over night or however long it takes to clear any fault codes or issues it has.

 

When cold these autoboxes dont like to change, especially if you have an aftermarket oil cooler on. I know mine doesnt, lockup can take a few miles to be available. Obivously they thrive on the oil being warm, with an aftermarket cooler it takes longer to warm up!

It makes no difference if you have overdrive on or off? the gear changes always select the same way. not sure with the lockup dident know they had it?? how would I tell from 4th and lockup? Iv reset the batt but only for an hour do you have an idea how many hours in total it should be disconnected to reset box ecu? cheers for your time mate!

Lock up makes it feel like it just changed up again from (OD)4th to 5th. (I know there isnt a 5th actually) If you let it do it on a light throttle at over 40mph you might only notice the rpm fall slightly again shortly after changing to 4th as the converter locks up. You'll know if you are in it when it shows around 2700rpm at 80. It drops the lock up if you hit the throttle or hit an incline.

I am not sure where the transmission ecu gets the temperature reference from but but it wont allow lock up till well warm - maybe it uses the main engine temp sensor. If you have a bad connection on that then it could be seeing cold the whole time and not enabling lock up. This would also kill max normal boost and have the engine stuck rich and drinking fuel too.

Lock up makes it feel like it just changed up again from (OD)4th to 5th. (I know there isnt a 5th actually) If you let it do it on a light throttle at over 40mph you might only notice the rpm fall slightly again shortly after changing to 4th as the converter locks up. You'll know if you are in it when it shows around 2700rpm at 80. It drops the lock up if you hit the throttle or hit an incline.

I am not sure where the transmission ecu gets the temperature reference from but but it wont allow lock up till well warm - maybe it uses the main engine temp sensor. If you have a bad connection on that then it could be seeing cold the whole time and not enabling lock up. This would also kill max normal boost and have the engine stuck rich and drinking fuel too.

Dont think iv experienced lock up? at just over 40mph the revs do drop but I thought it was changing into 4th? no revs drop thereafter. I will check the revs at 80 when I pick kids up from school. Engine temp sensor was loose coz when you boot it the needle jumped allover the place but had full service done which sorted that prob.

Engine temp sensor was loose coz when you boot it the needle jumped allover the place

 

That was just the T gauge sensor - there's another main sensor beside it - the bigger one - thats the one that gives the engine ecu its references. The connector is ripe for furring up with green oxide as are most connectors on a zed at this age. Certainly check it and clean it if necessary.

Engine temp sensor was loose coz when you boot it the needle jumped allover the place

 

That was just the T gauge sensor - there's another main sensor beside it - the bigger one - thats the one that gives the engine ecu its references. The connector is ripe for furring up with green oxide as are most connectors on a zed at this age. Certainly check it and clean it if necessary.

Oh right the two together! is that the yellow one? which isent in the best condition but I have cleaned it up could do with a new one as its very brittle but it did keep switching the fan on when the connection was broken...

Just replace it with 2 small spade type connectors crimped onto the end of the wires when you chop it off :) Doesn't matter which way round they go :)

Just replace it with 2 small spade type connectors crimped onto the end of the wires when you chop it off :) Doesn't matter which way round they go :)

I presume its a good idea not to let them touch?!

Lock up makes it feel like it just changed up again from (OD)4th to 5th. (I know there isnt a 5th actually) If you let it do it on a light throttle at over 40mph you might only notice the rpm fall slightly again shortly after changing to 4th as the converter locks up. You'll know if you are in it when it shows around 2700rpm at 80. It drops the lock up if you hit the throttle or hit an incline.

I am not sure where the transmission ecu gets the temperature reference from but but it wont allow lock up till well warm - maybe it uses the main engine temp sensor. If you have a bad connection on that then it could be seeing cold the whole time and not enabling lock up. This would also kill max normal boost and have the engine stuck rich and drinking fuel too.

Right Iv driven zed at 80mph and the revs were at 3100rpm so whats the score with that??

Im looking forward to the day this box works properly!!

I presume its a good idea not to let them touch?!

 

Just use insulated connectors :)

80 at 3100 is in o/d with lock up. 26.5/1000 approx.

 

Had similar probs with mine not changing as it should, was ECU - diognostics said all sorts of things. they were ok just changed the ECU and all was ok.

 

If temp sensor playing up engine would run realy rough!

80 at 3100 is in o/d with lock up. 26.5/1000 approx.

 

Had similar probs with mine not changing as it should, was ECU - diognostics said all sorts of things. they were ok just changed the ECU and all was ok.

 

If temp sensor playing up engine would run realy rough!

Hello mate, engine runs sweet so you think the ECU? so it does go into o/d and lock up? havent a clue what that means! these motors are a bit technical for my brain!! So where is the ECU located to? and maybe a rough idea how much a second hand one is to buy? Thing is ive tryed the diognostic test and it doesent work so no idea of fault codes? your starting to make me feel better mate :mac1:

O/D is fourth, button on gear lever. lock up locks the torque converter so no slip, gives direct drive. ECU is located under floor in passenger well. Try Andy Z in traders section to see if he has one, usually about £80.

Another possibility is the wiring, broken or dodgy connection somewhere.

You could try a good auto box specialist who would do pin test to trace it. QAS in Filton is the only people I know up that way that are v.good.

O/D is fourth, button on gear lever. lock up locks the torque converter so no slip, gives direct drive. ECU is located under floor in passenger well. Try Andy Z in traders section to see if he has one, usually about £80.

Another possibility is the wiring, broken or dodgy connection somewhere.

You could try a good auto box specialist who would do pin test to trace it. QAS in Filton is the only people I know up that way that are v.good.

I thought o/d was like sports mode? and 4th was 4th!! I know that some wires and pipes are very brittle under bonnet so could be dodgy wires? When you say the ECU is under foot well are you saying theres two in there? coz the main ECU iv ran the test on it with no fault codes (55) I can remember theres another box next to it silver I think?

Yep thats where it is.

For sport mode swithch on power button and swithch off o/d only goes up to third.

o/d is 4th.

when you swithch on does the power light flash at you 16 times I think that warns you that there is a problem with the autobox.

have you done an aoutobox diagnostic check. do a search on forum. you just need to move g.lever etc. and power light will flash codes at you.

Yep thats where it is.

For sport mode swithch on power button and swithch off o/d only goes up to third.

o/d is 4th.

when you swithch on does the power light flash at you 16 times I think that warns you that there is a problem with the autobox.

have you done an aoutobox diagnostic check. do a search on forum. you just need to move g.lever etc. and power light will flash codes at you.

I only have an o/d button mines a uk car! when the light comes on it just stays on, no flashes. Iv tryed the diagnostic test many times and it wont work :mad: so not sure if theres a different test for uk models? Good thing about where I live I have SWZ performance the zed specialist about 10mins drive so could tap them up and maybe borrow a ECU from them to check? then buy it if need be? appreciate your help mate posted many times about this! and had no replys!

You must have a power/hold switch by the gaer lever?

your power light should come on when you first switch on, then goes out, if it flashes thats a warning something is wrong!

Suggest you do take it Paul at SWZ, should sort you out.

You must have a power/hold switch by the gaer lever?

your power light should come on when you first switch on, then goes out, if it flashes thats a warning something is wrong!

Suggest you do take it Paul at SWZ, should sort you out.

Nah you only get them on the imports would be nice to have one though!!

Just had a look at ECU just to see if there was any loose connections thought id take a pic. I know the gold one is the main ECU so is the one on the left with the 'C' on the autobox ECU? there is a small box just behind the one with the 'C' could that be it???

Yep thats the auto ECU with the blue plug on it :)

Yep thats the auto ECU with the blue plug on it :)

Cheers andyduff :D