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R34Gtt Auto To Manual Ecu Problems?

havoc34
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havoc34 Enthusiast

havoc34

Posted
Posted

Hi all,

Need advice from those who have done conversions. I had my conversion (R34GTT box, manual parts) done about a year ago. But ECU was not changed. Noticed that around 5500 to 6000rpms seems it goes to rev limiting mode it doesn't allow to go pass that but when in autobox (before conversion) in auto mode it doesn't go pass 5500rpms before changing gears and in triptronic mode it does happen.

Is it because of the AUTO ECU?? Everything else runs perfect only this issue. So if it possible to just plug and play the Manual ECU? (Read in a thread in here that certain sensors won't work like the TCS) or is this only affect those converion that uses the R33 box.

Or is it because the coils or plug reaching their time to change?

Or the AUTO ECU has got Rev Limiter to protect the autobox itself??

Thanks for the help in advance.

Cheers

Daniel

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GTSBoy Grand Master

GTSBoy

Posted
Posted

On auto cars the TCU is a board inside the engine ECU. If you just use the ECU from an auto car to run a manual engine, it _should_ be OK. It's been done before many times by others. But, there are a few tricky things hiding in the ECU code that only come out to play under certain cicumstances. Here's a question for you. What else is modified on your car? Do you have a bigger turbo? The Nistune guys have worked out that there are early injection cuts that come in to play if the load on the engine gets to a certain (high, higher than can be reached with standard turbo) level when the TCS stuff is not working properly.

havoc34 Enthusiast

havoc34

Posted
  • Author
Posted

On auto cars the TCU is a board inside the engine ECU. If you just use the ECU from an auto car to run a manual engine, it _should_ be OK. It's been done before many times by others. But, there are a few tricky things hiding in the ECU code that only come out to play under certain cicumstances. Here's a question for you. What else is modified on your car? Do you have a bigger turbo? The Nistune guys have worked out that there are early injection cuts that come in to play if the load on the engine gets to a certain (high, higher than can be reached with standard turbo) level when the TCS stuff is not working properly.

Hi GTSBoy,

Besides HKS Turbo back exhuast and FMIC nothing else. TCS works properly as it should be. Turbo is stock standard. On the auto ECU and normal driving and spirited driving is ok but try to pull it pass 6k rpm on any gears it'll just won't go pass that.

Anyone experience that with tthe AUTO ECU after conversion?

Cheers

Daniel

R34mac Enthusiast

R34mac

Posted
Posted (edited)

I've found no differences at all between auto and manual ecu's (auto gearbox logic aside) and my car ran exactly the same after my manual conversion - no matter if I was using an auto or manual ECU. It was probably one of my old posts you read, regarding the TCS not working. Apparently the wheel slip sensors between some R34's are different - could either be different from auto to manual cars, or even S1 to S2 cars - I don't know for sure.

All I know is I still run an auto ECU in my car and it runs perfectly right up to the redline. If I run the manual ECU, TCS fails to work but otherwise runs exactly the same in every way. To muddy the waters further - Nistune flashed my auto ECU with a manual map and when I got it back TCS didn't function either. I had to get them to re-flash it with the old auto map and TCS came back.

And yes they are plug'n'play.

Edited by R34mac
havoc34 Enthusiast

havoc34

Posted
  • Author
Posted

I've found no differences at all between auto and manual ecu's (auto gearbox logic aside) and my car ran exactly the same after my manual conversion - no matter if I was using an auto or manual ECU. It was probably one of my old posts you read, regarding the TCS not working. Apparently the wheel slip sensors between some R34's are different - could either be different from auto to manual cars, or even S1 to S2 cars - I don't know for sure.

All I know is I still run an auto ECU in my car and it runs perfectly right up to the redline. If I run the manual ECU, TCS fails to work but otherwise runs exactly the same in every way. To muddy the waters further - Nistune flashed my auto ECU with a manual map and when I got it back TCS didn't function either. I had to get them to re-flash it with the old auto map and TCS came back.

And yes they are plug'n'play.

Hi Mac,

So that being said...Cos I suspect that my plugs may not be up to mark any more (yet to remove to see or even change), or could even be my coilpacks going? Cos normal driving it ok, Pulls hard until ard the 6k -6.5k mark that the said problem starts.

Cheers

Daniel

GTSBoy Grand Master

GTSBoy

Posted
Posted (edited)

It could well be that the coils are dying. Given that you have no extra boost in it, it makes sense that they might only play up at high rpm. Usually they are dying on people's engines that are at least boosted up, and when they misfire it tends to be as the boost comes on or at/near max torque (when the coils get under the most load).

Many, if not most, R34 coils have needed to be replaced by now.

Edited by GTSBoy
havoc34 Enthusiast

havoc34

Posted
  • Author
Posted

It could well be that the coils are dying. Given that you have no extra boost in it, it makes sense that they might only play up at high rpm. Usually they are dying on people's engines that are at least boosted up, and when they misfire it tends to be as the boost comes on or at/near max torque (when the coils get under the most load).

Many, if not most, R34 coils have needed to be replaced by now.

Hi GTST,

Well I guess so cos I'm on 12x,xxxkms now. That's what i was thinking too in that line.

Thanks for all the help

Cheers

Daniel

R34mac Enthusiast

R34mac

Posted
Posted (edited)

Hi Mac,

So that being said...Cos I suspect that my plugs may not be up to mark any more (yet to remove to see or even change), or could even be my coilpacks going? Cos normal driving it ok, Pulls hard until ard the 6k -6.5k mark that the said problem starts.

Cheers

Daniel

Could you test something out for me? Make sure the engine is up to temperature and try hit the 7000rpm limiter whilst using very low throttle.

My car had issues after I upgraded my exhaust to a 3" straight through - I'd accelerate hard and then hit a wall at 4500rpm - felt exactly like a rev limiter. The workshop I took my car to said the exhaust upgrade increased the boost pressure slightly and it was now beginning to blow the spark out on the spark plugs, so they weren't igniting the fuel in the cylinders. It only happened to me when I was using half throttle or more - at smaller amounts of throttle it'd rev out higher as usual.

So basically try accelerating with low throttle and see how high the revs go. If this sounds like your problem, it can be fixed by having your spark plugs re-gapped to .7mm or so (they're 1.1mm stock). Or just by buying new plugs which are gapped to 0.7 already.

I may be wrong. but see how you go.

Edited by R34mac
havoc34 Enthusiast

havoc34

Posted
  • Author
Posted

Could you test something out for me? Make sure the engine is up to temperature and try hit the 7000rpm limiter whilst using very low throttle.

My car had issues after I upgraded my exhaust to a 3" straight through - I'd accelerate hard and then hit a wall at 4500rpm - felt exactly like a rev limiter. The workshop I took my car to said the exhaust upgrade increased the boost pressure slightly and it was now beginning to blow the spark out on the spark plugs, so they weren't igniting the fuel in the cylinders. It only happened to me when I was using half throttle or more - at smaller amounts of throttle it'd rev out higher as usual.

So basically try accelerating with low throttle and see how high the revs go. If this sounds like your problem, it can be fixed by having your spark plugs re-gapped to .7mm or so (they're 1.1mm stock). Or just by buying new plugs which are gapped to 0.7 already.

I may be wrong. but see how you go.

Hi Mac,

No problems up to ard 6-6.5mark. but have not tried slow/low acceleration. Will try when i have the chance to.

Cheers

Daniel

  • 1 year later...
CHU801 Enthusiast

CHU801

Posted
Posted

Hey all,

I need help with my r34gt-t auto that I converted to manual, using r34gt-t gearbox and everything. it runs fine and everything with the auto ecu.

But when I put a r34 gtt manual ecu into my car it doesn't crank over? But I still hear the fuel pump prime.

Only asking this as I bought a power fc to suit my r34 gt-t but does not work in my car, but I tried the power fc into my mates factory manual r34 gt-t and it worked.

Can anybody give me some pointers or ideas why my car doesn't work with a manual ecu? When everyone is saying its "plug and play"??

Thanks chu801

GTSBoy Grand Master

GTSBoy

Posted
Posted

Well......it's not normal behaviour, so something must be wrong. Have you considered taking it to someone who knows the ECU and ECCS relay wiring of these things real well and let them have a poke around with it? There might be a loose wire in a plug.

Actually, thinking of that - make sure that when you plug the manual ECU in that you are pulling it up straight. I have seen once or twice an ECU that wouldn't work simply because it wasn't plugged in properly. Looked proper, but wasn't.

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