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RB25DET NEO stalls once its warm

Hey guys my RB25det R34 has recently developed a problem where the car decides to stall once it is warm, this tends to be when i am at traffic lights stopped or crawling pace, has also happened when ive been in the lower rev range but i have found that so long as i keep the revs above 3k rpm it doesnt happen. i have checked coolant temp resistances and they all look about right when cold its 3250 ohms and warm 230 ohms.

The wires to the o2 sensor have been cut for as long as ive owned the car and worked fine for 2 months then started this problem

so key points,

-Dies once warm

-Coolant temp sensor looks good

-seems to be fine with higher revs

car specs: STOCK RB25DET NEO with fmic, turbosmart bov to atmosphere, link g4 ecu

 

Thanks in advance

Edited by L0N3S0MER4NG3R
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If you are using the ECU that come with engine. It might be throwing a code, if you can plug it into a reader. You could also bypass the sensor with a specific range resistor to give you what ohms you want. Good luck.

1 minute ago, WHITEBEAST said:

If you are using the ECU that come with engine. It might be throwing a code, if you can plug it into a reader. You could also bypass the sensor with a specific range resistor to give you what ohms you want. Good luck.

I am running a link g4 ecu, but don't have a cable so can't see what's happening with it at the moment. Don't need to bypass the coolant sensor as I believe it's working fine, I just logged what happend around then

Just now, Binarydata said:

Check the CAS. I was having the same issue. If you pull it off (after marking where it was) it should spin easily and freely. Swap it out for another one if you can.

Hi, have brought one this week but wanted to check everything simple first, is there anything I need to do or can o just mark where it is pull it off and throw a new one in the same way

I had an issue with a V8 CAS, it sounds the same. The contacts stuff up in them. If you tip cold water on CAS at front of the engine. Does it start sooner?

Edited by WHITEBEAST
  • 2 months later...

so ended up borrowing my mates link g4 cable and turns out i have a link g4+, i logged a drive and when it died the map sensor went nuts, wiggled the wires and away it went again. just cut the wiring out and redo it? screenshots from moment it died (it was running normal in the first photo)

Log 2017-09-21 12;55;58 pm.llg

map sensor reading.png

Edited by L0N3S0MER4NG3R
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