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New torque converter/auto box issues


Milo500

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I'm hoping it's not the box, and it feels exactly the same as the last box, so I presume it isn't.

 

It redlines in neutral but is the same problem in every other gear.

 

I have a sneak suspicion that it is the boost controller, as the screen was smashed about 5 months ago around the time when the gearbox did this, but because it was slipping in every gear badly, I presumed this was it's final blow.

 

I have another controller coming and will see how It goes as I cannot change the boost settings on my current greddy profec.

 

Also I will add, the air fuel ratio peaks extremly rich when this happens.

Edited by Milo500 (see edit history)
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no this is due to the resistance through a bad connection,as the demand becomes more for the spark it cant deliver the current/ signal to coil too spark in time causing misfire

http://www.mkivsupra.net/vbb/showthread.php?61141-How-To-Refurbish-coil-pack-connectors

 

If that was the case how would I know if one was not working correctly at high rpm...the demand is the same (spark wise) at 5kwhether it be at 0.7 bar or 1.5 bar No?

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No, the required spark energy to jump a given spark gap increases exponentially with cylinder pressure, so the coil has to charge to a higher level to reliably spark as boost rises. As RPM is also rising it has to attain that energy level faster, too....The real answers are mappable dwell time and Bosch Motorsport coils, that pack enough Joules to drop a horse, but really healthy stock coils, with the connector shells and contact terminations in good order will suffice in many cases.

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No, the required spark energy to jump a given spark gap increases exponentially with cylinder pressure, so the coil has to charge to a higher level to reliably spark as boost rises. As RPM is also rising it has to attain that energy level faster, too....The real answers are mappable dwell time and Bosch Motorsport coils, that pack enough Joules to drop a horse, but really healthy stock coils, with the connector shells and contact terminations in good order will suffice in many cases.

 

Thanks Chris

 

You don't have to change them but if you want your can to run correctly , you will have to change them like 90% of owners have had too over the years , put it this way I'm on my 5th turbo,3rd fuel pump, 3rd set of injectors , 3rd intercooler , 2 crank pulley , 2 set of coils , 2nd set of coil clips ,2nd cam sensor probably 4th battery 3rd set of wheels and 10th set of tyres.

all things have a life and it looks like your coils or clips have passed theres

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Thanks Chris

 

You don't have to change them but if you want your can to run correctly , you will have to change them like 90% of owners have had too over the years , put it this way I'm on my 5th turbo,3rd fuel pump, 3rd set of injectors , 3rd intercooler , 2 crank pulley , 2 set of coils , 2nd set of coil clips ,2nd cam sensor probably 4th battery 3rd set of wheels and 10th set of tyres.

all things have a life and it looks like your coils or clips have passed theres

 

So... I have changed the plugs to -8 ones and now it doesn't seem to cut. However it starts making a wastegate chatter noise above 5k ish and doesn't go any higher in the revs. Is odd, as it's on a screamer pipe you can clearly tell the gate is open.

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The coil packs are a possibility, however I am starting to think it is the speed sensor on the back of the gearbox

 

 

Because this problem was apparently same with previous box it looks to be an old electrickery problem that your new box has inherited?

 

But to confuse the issue even more, the Aristo box has 3.769:1 diff-ratio ratio gears in the no. 2 speed sensor which has also confused the gear-change tables?

 

These gears can be swapped to increase or decrease the rpm of gear-changes.

 

Info here. http://www.mkivsupra.net/vbb/group.php?discussionid=229&do=discuss

 

And here. http://www.mkivsupra.net/vbb/group.php?discussionid=223&do=discuss

 

Ellis ran a converted Aristo box in his Supra, maybe he has input re. resulting gear-change speeds?

 

:yeahthat:

 

 

As I have already confirmed, the Aristo no. 2 speed sensor gears are definitely part of the problem, yet only by 100rpm.

 

You also have another electronic issue that has lowered the engine rpm limit.

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"You also have another electronic issue that has lowered the engine rpm limit."

 

As I have already pointed out there is a Rpm limiter that is to do with the park /neutral/ drive selection and I think it's around 5000 rpm - even if the box selects gears and the engine starts if the ecu thinks it's in park the limiter kicks in .

The ECU has a few "limiters" each at a different rpm and each for a different reason and they do not always show up on self test of the ECU

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Please follow peoples advice that you've asked for. at least 4 people have said change the coil pack clips and coils for a known good set. I can't see how a speed sensor would be related at all.

 

I have done everything people have suggested bar the coil packs...that is because I have not got round to getting a set to borrow yet. And yes as I have gone from a tt box to an aristo box, a speed sensor could be part of the problem?

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:yeahthat:

 

 

As I have already confirmed, the Aristo no. 2 speed sensor gears are definitely part of the problem, yet only by 100rpm.

 

You also have another electronic issue that has lowered the engine rpm limit.

 

Hi David.

 

I have read that, and 're read it again to make sure I didn't miss anything.

 

The aristo box I bought didn't come with one of the speed sensors (on the right hand side of the box when looking at the tail shaft end).

So I had to take it out of the old tt box. As it is now doing the same thing it was doing before I changed the box, is what is making me think that it could be that speed sensor, as it is the only part I took from the old box

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