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R34 gt4 non turbo to rb25det conversion

Mussy
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Mussy Contributor

Mussy

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42 minutes ago, GTSBoy said:

Have you opened the bleed screw on top while running and observed coolant flowing through there?

Yes coolant is flowing, have bleed from both screws one on thermostat and one on idle control. Coolant is flowing smooth without any air. There is no blockage as used air line and water was instantly coming out of all pipes.

 

This is a tricky one 🙈

Mussy Contributor

Mussy

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Hi guys mights have found something, started engine when cold removed the plug for the gearbox speed sensor, knock sensor neutral sensor, idle went up higher which is what i need.

possible chance car doesnt think its in neutral?

 

will have to dig deeper

GTSBoy Grand Master

GTSBoy

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40 minutes ago, Mussy said:

possible chance car doesnt think its in neutral?

Nah. My neutral switch is working and the ECU doesn't give 2 shits whether it's in Neutral or not (when it comes to idle speed, that is).

Might be more the case that your knock sensor is telling fibs and making the ECU freak out and pull timing. Have you verified the actual timing at the crank?

I think you should hook up a Consult scanner of some sort (an actual scanner or USB software one like NissDataScan) and see what the ECU is doing. You will be able to see what timing it is commanding, how many "steps" it is putting out to the IACV, and various other things that might be instructive. Not taking advantage of the fact that you can connect to the ECU and see this stuff is really making it hard on diagnosis of weird shit like this.

Mussy Contributor

Mussy

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Posted (edited)
1 hour ago, GTSBoy said:

Nah. My neutral switch is working and the ECU doesn't give 2 shits whether it's in Neutral or not (when it comes to idle speed, that is).

Might be more the case that your knock sensor is telling fibs and making the ECU freak out and pull timing. Have you verified the actual timing at the crank?

I think you should hook up a Consult scanner of some sort (an actual scanner or USB software one like NissDataScan) and see what the ECU is doing. You will be able to see what timing it is commanding, how many "steps" it is putting out to the IACV, and various other things that might be instructive. Not taking advantage of the fact that you can connect to the ECU and see this stuff is really making it hard on diagnosis of weird shit like this.

Good point, as i had to re wire the knock sensor plugs, not sure if i switched them while wiring left on right and right in left. Timing will check and get onto datascan. Thank you guys 😎

Edited by Mussy
GTSBoy Grand Master

GTSBoy

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Nah, actually it's fine. I had a little look see at the stock** timing map, and in the conditions you were running, 3700rpm and no load, 50 is actually the correct value.

** Stock, but stretched on both the load and rpm axis. But the values in the main part of the map are essentially the same as stock.

image.thumb.png.3f02b3766dbf0331170dfeb99c012551.png

Mussy Contributor

Mussy

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5 minutes ago, GTSBoy said:

Nah, actually it's fine. I had a little look see at the stock** timing map, and in the conditions you were running, 3700rpm and no load, 50 is actually the correct value.

** Stock, but stretched on both the load and rpm axis. But the values in the main part of the map are essentially the same as stock.

image.thumb.png.3f02b3766dbf0331170dfeb99c012551.png

Glad you sent this got me thinking about cambelts and all sorts 😂 so i guess everything is fine but still no cold start high idle arggghh

 

only thing left to do now is compare data from an actual r34 gtt turbo and compare

 

there must be something i must have missed out 🙈 hope its not ome of these posts where there is no result 😂

joshuaho96 Veteran

joshuaho96

Posted
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On 5/14/2023 at 3:00 AM, GTSBoy said:

Nah. My neutral switch is working and the ECU doesn't give 2 shits whether it's in Neutral or not (when it comes to idle speed, that is).

Might be more the case that your knock sensor is telling fibs and making the ECU freak out and pull timing. Have you verified the actual timing at the crank?

I think you should hook up a Consult scanner of some sort (an actual scanner or USB software one like NissDataScan) and see what the ECU is doing. You will be able to see what timing it is commanding, how many "steps" it is putting out to the IACV, and various other things that might be instructive. Not taking advantage of the fact that you can connect to the ECU and see this stuff is really making it hard on diagnosis of weird shit like this.

Shockingly on the RB26 R33 ECU it definitely looks for the neutral signal for idle target. If I coast in gear and then press the clutch in it will idle high like 1200 rpm, then if I go into neutral and wiggle the stick it will drop it to 950 rpm.

 

On 5/18/2023 at 4:00 AM, Mussy said:

IMG_0270.thumb.jpeg.ed5895447c16b0196898082cfbfe7917.jpegIMG_0271.thumb.jpeg.fef20f2858eb39bdff2fd13bf41e46e8.jpegIMG_0272.thumb.jpeg.81f71602f4cc3701690280041b713f25.jpegIMG_0273.thumb.jpeg.1e6e42e4d9c881544516b1556468417c.jpegIMG_0276.thumb.jpeg.5b368a62fc5b3c8db9ff8457d5dd0f7f.jpeg

IMG_0274.mov 17.76 MB · 1 download  

 

IMG_0275.mov 25.83 MB · 0 downloads  

 

Finally got datascan attached are pictures from data 

 

 

FYI, you can use the logging function in NDS1 instead of taking a video. I'll try to read through it anyways but something to think about in the future.

GTSBoy Grand Master

GTSBoy

Posted
Posted
1 hour ago, joshuaho96 said:

Shockingly on the RB26 R33 ECU it definitely looks for the neutral signal for idle target. If I coast in gear and then press the clutch in it will idle high like 1200 rpm, then if I go into neutral and wiggle the stick it will drop it to 950 rpm.

Same on others. But we're talking about stationary (<5km/h) conditions here.

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