Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/389134-r34gtt-auto-to-manual-ecu-problems/
Share on other sites

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.

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

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

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

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

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

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

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...

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

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I'm not up to date on the latest, but for basic modifications like pod filter, lower springs etc you can get a modification permit at the time of inspection.  For more serious modifications you will need engineering.  Intercoolers used to fall into the mod permit rule but its been a long while since i looked it up.   Either way you will be able to get it registered, just a case of $300 vs $3k . 
    • Hi everyone! I’m the new owner of a 1996 R33 GTS-T, I’ve purchased this car over from Queensland and brought it to Western Australia and I’ve found that there is a hole cut out in the engine bay for the FMIC that enters into the wheel well (fender liners are in the boot). For anyone that has had to get their car over the PITS here, will this be a major issue?   
    • Yeah I've spotted this one too, whenever it's lotto superdraw week and I'm browsing car sales dot com for my new ride They must be dreaming, maybe it's worth 150k for the link to Brock?
    • 100% accurate!  We are a pack of know it alls....  But, I bet people go to you when they have a problem! I've been on a bit of a clean up rampage too over the past month!  I've thrown more shit in the bin over the past 2 weeks than I have in the past 3 years combined! Anyway, it's all good fun being different! My wife sometimes does not agree!  
    • ADHD in all form isn't about "can focus, or can't focus" or is hyper active or isn't etc.   It's all a dysregulation. Either time feels to be stationary, or time just vanishes in a split second. We are either under focussed on the task at hand (as we're over focussed on our surroundings) or we have no idea an atomic bomb went off beside us as we're so hyper focussed and locked in on things.   Not to mention the rapid fire thought process. What it takes a "normal" process to think up a solution to a problem, ADHD will be able to give you 5 different ways to solve the problem, and the pros and cons of each. While we can be highly impulsive and lack the ability to "control ourselves" we can also become paralysed with the inability to make a decision for ourselves. While most of us have an OCD like requirement for perfection, we lack the ability often to remain focussed to get things to a perfect state. Those with undiagnosed ADHD as adults, can often find the last part actually stops them ever attempting to do things that they have the ability to do, as the reasoning is often "if I can't do it perfectly, it's not worth doing"   As for projects... Ha ha ha, I still need to take the other half of my wall trim down in the Fiance's office so I can paint it. Need to finish digging and running the back yard drains, my R33, getting the Ninja bike registered (now being sold), the moped project, fixing either of the lawn mowers so they're reliable, along with a myriad of other things.   It's why I've been going through lately and just being brutal and clearing projects off that I won't actually ever complete. IE, moped will go to the tip, or be given away, bike is being sold, Subaru project being sold, some parts for other projects given away. Or I've been making myself focus on one thing at a time, by ticking off the smallest quickest ones first.   There's also a reason by our mid twenties we seem to be "know it alls", as we've all been down some of the weirdest and oddest rabbit holes when you follow the dopamine trail. It's often also why we're more a jack of all trades, but not a master of one.   However, pretty much all of my hobby projects, in one way or another, all come back around to automotive. That's my zen area.
×
×
  • Create New...