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When the car is at idle (cold or at operating temp) and you put it in gear the revs jump immediately to 2000rpm, if you keep the clutch engaged and take it out of gear this does not happen, only when you put it in gear, any gear?

This problem is driving me nuts, I have checked for vacuum leaks, installed new hoses, new rubber plug for inlet rocker cover etc etc.

Yet to clean IAC unit, waiting for gasket.

Standard COILS, NGK Ir's 1.1mm (fairly new), BLitz BOV, pretty stock std setup.

I have read about a neutral switch problem but this is the opposite I believe, it is only when in gear.

I still have a high cold start idle too at 2000rpm.

Please HELP!!

This sound like an idle air problem

i.e. the ECU doesnt know how much air to take in at idle, so it "hangs" and "searches" for an idle.

I've got the exact problem with my x-trail at the moment.

Its an easy fix for me, just need an ECU reset.

i dont know how stag ECUs work, but someone here should know how to perform an "Idle Air Relearn", most nissan cars have the function.

BUT, could be the IAC valve, try that first!

From what I've heard, RB engines have this problem heaps, and its solved by cleaning the IAC, theres a How-to somewhere on here...

http://www.skylinesaustralia.com/forums/Di...nd-t110431.html <- that might help...

This sound like an idle air problem

i.e. the ECU doesnt know how much air to take in at idle, so it "hangs" and "searches" for an idle.

I've got the exact problem with my x-trail at the moment.

Its an easy fix for me, just need an ECU reset.

i dont know how stag ECUs work, but someone here should know how to perform an "Idle Air Relearn", most nissan cars have the function.

BUT, could be the IAC valve, try that first!

From what I've heard, RB engines have this problem heaps, and its solved by cleaning the IAC, theres a How-to somewhere on here...

http://www.skylinesaustralia.com/forums/Di...nd-t110431.html <- that might help...

Hey mate,

Yeah there seems to be a lot of threads on this one, no definite 'this is how you fix that exact problem', so I have to try all methods I guess, I just read a post where a guy had the same type issue, it was his ECU connector was not plugged in properly, if that is all it is whoot! easy fix, although I have never been in there to disrupt anything yet! :)

I for the first time connected to the car last night using 'OBD Data Scan full version', very interesting read outs, everything appears ok voltage wise, could be an issue with neutral swtich?, cyclinder 1 has a really bad result when tested in a 6 cyl test. Did an ECU reset and cleared all codes!

I received fault codes 17? and 43 (boost sensor) so all in all that is okay until I figure out what is wrong with the boost sensor??

I need to set my TPS correctly with a multimeter this may also be wrong, but looking forward to cleaning the IAC as soon as I get the gasket or goo and time this weekend.

I must search the car again for more vacuum leaks, as I can still hear a very slight hissing noise around the front plenum area, all hoses are new now, all are fixed tight, so maybe a gasket leak from the plenum is adding to the whole equation/problem or a dodgy injector?

Ahh cars eh! :D

As I have 2 x r34's, I have not driven the turbo one for about a week now, every night after work thought I have been checking the car for the problem and testing, resetting the TPS voltage which I still do not think is giving me any decent readings. (not sure how my multimeter is to read between .045 & 5

I decided to start her up and let her warm for a drive, I have to unplug the TPS switch for the idle to drop down to normal (could be a TPS replacement now), I took her for a good run and she is driving very nicely until I stop and put in gear, the same thing happens the car revs high and in neutral it is fine. Just as I was putting her back in the garage, I was halfway to backing in (ramp is on a slope) and it stopped reving at high when in gear, I sat for about 2 mins testing this (in and out of gear and it appeared fixed) as soon as I got on the flat when inside the garage it started again. I am thinking there must be some cable not earthingn now that is causing this, casue when on that angle it the problem completely went away. I gather there are many earths on this vehicle, but where to start???? It must be hanging lose somewhere.

Ah forgot to mention that when checking TPS using the white wire with Ignition ON/Engine OFF on RB25DET NEO, I do not seem to get a good reading, my power voltage it fine at 5V so I know at least it is has power to work, but getting a reading on my multimeter is sooo hard to get the magic .045v, it really does not matter if I move the TPS clock or anti as the voltage really does not change that much .3 -.4, perhaps I am not using the correct setting to get a reading on the meter, although I have tried all settings?

Still does not explain however why when the TPS is disconneted and idle goes to normal that when a gear is engaged the revs go straight back to 2000rpm, I will get some gasket goo today and clean IAC unit while I am at it. I still reckon there is a bad earth hanging somewhere, any ideas guys??

Hmm i have code 17 & 46 also, I think these are both fuel injection circut/grounding problems?

I really cannot find a definitive answer on these fault codes for the rb25det neo 6 engine, anyone out there know??

Thanks

Hmm i have code 17 & 46 also, I think these are both fuel injection circut/grounding problems?

I really cannot find a definitive answer on these fault codes for the rb25det neo 6 engine, anyone out there know??

Thanks

I don't know about the stagea, but for the gtt those codes are,

17: abs-tcs control unit circuit.

46: throttle motor sensor signal circuit.

I don't know about the stagea, but for the gtt those codes are,

17: abs-tcs control unit circuit.

46: throttle motor sensor signal circuit.

Hey mate, just to clarify this is happening on my R34 GTT 1999, good to hear from another fellow KIWI.

Is the 46 code relating to the other sensor opposite the TPS on the TB of the NEO6?

  • 3 months later...

Sorry to revive this thread but I have this exact same problem with the idling in gear at 2000rpm (and on cold start) but normal idle when neutral and stationary.

It has only recently developed and I have not done any new mods recently to the car to cause it.

I have a consult cable and I have no error codes. I reset self learn and the problem went away for 1 trip and then came back on next startup.

Was this problem ever fixed?

Car: R33 GTST RB25DET

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