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Power Loss On Downshifts, Bouncing Idle And Slight Hesitation At Specific Rev Point -R34Gtt


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haha thanks man, will keep you in mind if I dont find one in Sydney.

Does anyone in Sydney have a NEO CAS that I could borrow for the weekend??

You can keep mine meanwhile, its fully functional just need to see if its the culprit of my problem. I have the timing gun and my base timings set to 15deg

R33 Series 2 1997~1998 fits

R34 GT-R fits

hey you got a series 2 R33 ay Johnny? Do u remember I met you once in the city @ Darling Harbour, you gave me a fuel damper part something... ;)

yeah I do (again) lol...

vaguely, was a fuel check valve?

If I still had that S2 I could have let you borrow the CAS as it used the R34 NEO CAS - however my current shit box uses the metal CAS so can't really help :(

yeh fuel check valve something lol, thanks no worries mate, lets see if theres anybody else on here with a NEO CAS in Sydney

Edited by rondofj

Also I'm confused about the coolant temp sensor - I know the one going to the ECU is the one to test/change not the one going to gauge, and then u have a third element, the thermostat which some people reckon is good to change??

yes 3x elements..

1x sensor (single wire) goes to your dash to show a useless needle

1x sensor (dual wire) resistance base, goes to your ECU to report back coolant temperature, this is also used to determine the enrichment values when the motor is cold.

thermostat aids the car to get to the right operating temperature fast, R34 GT-t like to operate around 90 degrees, R33 GTS-t like to operate around 80 degrees - I once bought a R34 GT-t thermostat and installed it into my car.. worst move ever LOL.. now I run the correct one.

The faster the car warms up, the less fuel it will used (based on coolant enrichment).

In your PowerFC menu.. there's a table that shows you water temp vs. injection correction - this defines how much additional fuel is required in vacuum and 100kPa+.. column one will have a lower valve than column 2 naturally.

Temps read as expected- I think it was 15C at startup-not sure will check again, but it goes up gradually with warming up/ driving, 32C, 50,65, 78,- was 78C for the rest of the drive last nite including power pulls before shutdown. This powerfc reading is taken from the coolant temp to gauge right? Or the one to ECU.

Sweet man, that confirms that the coolant temp to ecu is working well, as its talking to the ecu which is displaying the different temps with time, tonites drive start up was 23C and crept up to 73C after which I didnt check. Leaves the O2 sensor to test, TPS maybe and of course borrow NEO CAS :S

One other thing I get these 2 values 23 degrees under Ign Cor change from 24 to 23 to 15 degrees everytime u go in to check- is this normal? See pic

post-49401-14066302955451_thumb.jpg

That's the current ignition value being read off the map and the adjustment is a master trim - however temporary.

That means you can add or subtract a blanket timing value on top.

I just drove with O2 feedback disabled in power fc and the O2 sensor plug disconnected ( this didnt throw up engine check light?).

Strange thing the power fc sensor check still shows 0.2V for the O2S field with the sensor disconnected.

Drove the same, bogged down for 5secs on uphill downshift :(. My engine light mostly but not always flashes during approx 7000rpm+ in second. Peak values for knock remain low but airflow always shoots up to 4.9V+, is this normal for that gear n rpm? I think thats what flashes the light because even inj duty doesnt go past 75%

Edited by rondofj

Try and borrow a data logit kit from someone off the forum and do a log. That way you'll have in essence a data cube from which you can see what's happening.

I sold my kit a while ago when I sold my old car however if you can borrow one I'm more than happy to help you diagnose your problems for a few beers lol

  • Like 1

yeh it goes 4.9V+ all the time, isnt that normal at high boost/rpm?

How was it scaled? using the default Z32 AFM scaling or custom?

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