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ud wanna be 100% sure that the knock sensor is faulty causing it to read knock all the time.

it would actually be funny if the mines ecu is making the engine knock seeing as u seem to love it so much

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but r&r on full throttle until it reaches the set boost so theres a mixture of problems in my engine. which all adds up coz the o2 sensor and knock sensors are faulty.

dam i forgot about mixture. your right, it has to be the o2 sensor if theres a mixture involved. i apologise for all the stupid advice, you were right all along

Okay, I'm going to be rational and try and explain this nice and clearly, because you don't seem to be listening to anyone. Okay. I personally I think you need to try and eliminate the variables - standard problem solving approach.

Take the car back to as standard as you can, factory ECU, remove any boost controllers or boost-t's. Now test the car - if under these conditions, you've resolved the issues - you've identified that one of the things you've removed was causing the problem. You can start adding the parts back in - one at a time - to try and figure out which one it was, and work it from there. Now (if everything is working right) would also probably be a good chance to run it up on the dyno to see what you have as a starting point.

If, however, you continue to have problems when you're back to a near-stock condition, you also have information to work from. You now know it's not something you've added which is causing the problems but something more fundamental - whether it's anything from AAC, spark plugs, coils, or any number of things. Certainly, if your mechanic has identified that your O2 sensor and knock sensor are faulting - fix those, but don't expect that to magically resolve your issues. It should be fairly straight forward to identify what the cause is once everything is fairly stock.

Problem solving is easy - take things one step at a time and eliminate variables. You'll have this figured out in no time, and you'll be able to start to wind the power up from a solid standing point rather than trying to add modifications to a car that seems to have underlying problems.

ive got a brand new o2 sensor so will put it in on sat.

and the knock sensor was reading it knocking all the time as well so thats why it could be sending it into r&r.

il just fix these things and see what happens because im getting barely 280km to a full tank of 98 not boosting much so something is wrong.

if these dont change anything then i will sell the ecu and get something else obviously.

and my coils were new about 4 months ago and they are heavy duty ones that are in my mates 25det 32 pulling about 250kw. might try his coils and see what happens so can find out if mine are faulty or not.

i havnt ignored anyones points of view about anything im just hearing totally different things over here compared to oz. the tuner said the mines will work fine because the standard map was fine. but the real time map was r&r all over the place. so he showed me what it should be doing compared to what its actually doing.

This does not send it into R&R, this sends the ecu onto the stupidly rich no timing safety maps because it thinks the things about to explode.

Well nistune don't do the R33 as yet to my knowledge (although there are ways around this) but:

Mines ecu

Toshi ecu

Dr Drift ecu

EFI ecu

What do these have in common? They have been modified (some sort of daughterboard installed) to accept a tuned chip.

What are the differences? Mines is in Japan, the second two in Australia and EFI is right there in your home town of Christchurch and therefore the only one who can tune the chip on your car on the dyno.

As I recall early on in the piece you actually went to EFi and they offered you a price to replace the fuel pump, fit a fmic and chip and tune your ecu. This is still your best option although you didn't want to pay the money. You could have done the fmic and pump yourself to save money although it sounds as though you would be best to leave it to the professionals.

EFI have a good reputation as a performance workshop and as tuners and if they did the work they would fix any boost leaks and tell you if there were any other problems that need fixing.

(PS my RB25 would still make 245awkw with the o2 sensor disconnected so while it is good to replace it if it is dud don't expect that to make any difference to your power problems).

Okay, I'm going to be rational and try and explain this nice and clearly, because you don't seem to be listening to anyone. Okay. I personally I think you need to try and eliminate the variables - standard problem solving approach.

Take the car back to as standard as you can, factory ECU, remove any boost controllers or boost-t's. Now test the car - if under these conditions, you've resolved the issues - you've identified that one of the things you've removed was causing the problem. You can start adding the parts back in - one at a time - to try and figure out which one it was, and work it from there. Now (if everything is working right) would also probably be a good chance to run it up on the dyno to see what you have as a starting point.

If, however, you continue to have problems when you're back to a near-stock condition, you also have information to work from. You now know it's not something you've added which is causing the problems but something more fundamental - whether it's anything from AAC, spark plugs, coils, or any number of things. Certainly, if your mechanic has identified that your O2 sensor and knock sensor are faulting - fix those, but don't expect that to magically resolve your issues. It should be fairly straight forward to identify what the cause is once everything is fairly stock.

Problem solving is easy - take things one step at a time and eliminate variables. You'll have this figured out in no time, and you'll be able to start to wind the power up from a solid standing point rather than trying to add modifications to a car that seems to have underlying problems.

thats fantastic advise thanks mate. i went back to fully standard engine not to long ago for a track day. result was much slower but no problems except it spiked up to about 9 and a half psi. i put the boost t in and set it to the same boost as standard. it hit boost alot quicker and spiked about the same. but i will fix these things as i already have the parts and if nothing changes i will go back to standard and work from there. cheers man

This does not send it into R&R, this sends the ecu onto the stupidly rich no timing safety maps because it thinks the things about to explode.

isnt that r&r? makes it stupidly rich and knocks back the timing?

Dude, you haven't listened to a thing anyone has said.

The Oxygen sensor does not affect power in any possible way

As someone has said you could stuff a chicken sandwich in the hole and you would still get the same power.

The oxygen sensor helps the ECU cycle between rich/lean on cruise so as to obtain the best fuel economy.

If you want to avoid R&R, sell your mines ECU and get a proper standalone unit, or use a piggyback on the standard one (which is cheaper anyways)

Mines ECU might seem cheaper now (it isnt), but is it worth blowing your motor?

im taking all this advise in mate what have i said that tells you i havnt listened?

what would explain ( on the standard ecu running 7 psi on the boost t ) at full throttle until it hits 7psi it fully retards the engine and doesnt pull at all? change the boost to any psi and its always the same.

im taking all this advise in mate what have i said that tells you i havnt listened?

what would explain ( on the standard ecu running 7 psi on the boost t ) at full throttle until it hits 7psi it fully retards the engine and doesnt pull at all? change the boost to any psi and its always the same.

Because the ECU you have is running too rich and causing a misfire, or the ignition is too advanced causing knocking so it pulls the timing out, or it is just reading too much airflow and goes into 'shit we are running infinite boost and going to explode' mode.

Standard ECUs are known to do this as soon as you up the boost, they are reading way more air than they are designed for so they richen the mixture up and pull all timing. It is supposed to happen as a safety feature, you need to get it tuned to fix the issue.

Because the ECU you have is running too rich and causing a misfire, or the ignition is too advanced causing knocking so it pulls the timing out, or it is just reading too much airflow and goes into 'shit we are running infinite boost and going to explode' mode.

Standard ECUs are known to do this as soon as you up the boost, they are reading way more air than they are designed for so they richen the mixture up and pull all timing. It is supposed to happen as a safety feature, you need to get it tuned to fix the issue.

ok sweet well will fix these things see how it goes and if its no good probly get rid of the ecu and might get a safcII or something for now then

ok sweet well will fix these things see how it goes and if its no good probly get rid of the ecu and might get a safcII or something for now then

SAFC is just as expensive as a nistune to get installed, might as well go the full hog if you are going to do it.

I dont think its fair either to say the mines ecu is definitely the issue. How do you know that??

Do you have the old standard ecu to swap back in and try?

The ECU itself isn't the cause, it is the fact it is not tuned for his car. Same goes with the standard ECU, he has modded his car to an extent where the standard tune is not coping hence it pulling ignition and making the car run very rich.

i go into R&R after 9psi an i have some IMPUL ecu thing, i checked it out on the dyno and its a bit rich after 5,000RPM but better then the stock computer

i make 255HP 188KW at 9psi with 3" exhaust and pod filter, anything after that R&R i drop a lot of power goes super rich and retarted timing!!! that .... is the ECU doing that prolly the same as your mines one!!! i cant wait to get my PFC in thats sitting staring at me on my desk :P

my honest advise to you,

replace o2 sensor

replace fuel pump if your worried about it

New spark plugs

clean all your coils with silicone spray

Give your car a service! oil, filter, fuel filter etc

check for boost leaks and tighten all your clamps

Throw your boost controller out and get a new one make sure its not an issue

and put the stock ecu back in!!!!

throw it on the dyno see what its doing and post up the map and results here then everyone here thats trying to help will be able to help you much better!!! if you cant do this then i dont think anyone will be able to help you.

The ECU itself isn't the cause, it is the fact it is not tuned for his car. Same goes with the standard ECU, he has modded his car to an extent where the standard tune is not coping hence it pulling ignition and making the car run very rich.

The only mods he has done is an exhaust and upped the boost. The first issue to me is the boost spiking, this to me identifies something else is wrong.

If he drops the boost I cant see why the standard ecu cant cope or even the mines for that matter. Its not like he has considerable modifications. I agree that a tune would help a lot but it doesnt appear to be the issue yet.

The only mods he has done is an exhaust and upped the boost. The first issue to me is the boost spiking, this to me identifies something else is wrong.

If he drops the boost I cant see why the standard ecu cant cope or even the mines for that matter. Its not like he has considerable modifications. I agree that a tune would help a lot but it doesnt appear to be the issue yet.

If you read the title of the thread you will see that the focus of the OP is to go faster. To do that he will need a tunable ecu. If he goes to EFI they will sort out his other problems. His own understanding of how things work appears to be limited.

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