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


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Just having it for fault diagnosis it's worth it, even if you don't do any tuning. If there was one aftermarket gauge to have on the dash, on a tuned car, this is it.

True enough for anything over 100kmh with a power run. The 97% of the driving you use a street car for however can be done with a wideband and some tinkering. The power runs is what the dyno is for but that is really only a small fraction of the time (money!) it takes for a tuner to tune the car, but I agree - it's no dyno replacement.

In the 7 years I have been taking my car to Scott he has never " road tuned " either of my cars and both my cars run fine sub 100kmph, the 32 has got over 600km from a tank full :)

I would prefer using the dyno as it is a controlled environment

A wide band is good to have but how accurate do you think a $300 kit is given the lab grade ones dynos use are $1000+ just for the sensor and then have the ability to tune yourself while driving

Just having it for fault diagnosis it's worth it, even if you don't do any tuning. If there was one aftermarket gauge to have on the dash, on a tuned car, this is it.

Agreed, and if you get something like XGTRX has posted if it can light up the shift light as a lean warning and pissible drop boost it would be a good thing

A wide band is good to have but how accurate do you think a $300 kit is given the lab grade ones dynos use are $1000+ just for the sensor and then have the ability to tune yourself while driving

Any sensor is only good if it is tested and compared while in use. A $1000 lab sensor can easily get carbon impregnated and fail (usually from running cars too rich) just as easily as a $100 Bosch sensor.

The best option I believe is to compare the dyno gauge to the in-car Wo2, that way you will know something is wrong when there is a discrepancy. Of course you will need a third to check which one is faulty...

I have been to many dyno's over the last few years, and fixed a few also, most of the tuners down here are using Bosch sensors as they are cheaper to replace when they fail.

  • Like 1

Any sensor is only good if it is tested and compared while in use. A $1000 lab sensor can easily get carbon impregnated and fail (usually from running cars too rich) just as easily as a $100 Bosch sensor.

The best option I believe is to compare the dyno gauge to the in-car Wo2, that way you will know something is wrong when there is a discrepancy. Of course you will need a third to check which one is faulty...

I have been to many dyno's over the last few years, and fixed a few also, most of the tuners down here are using Bosch sensors as they are cheaper to replace when they fail.

True all O2 sensors should be tested and calibrated accordingly against a known working one or two, but do you think people are buying these O2 kits and then running them up on a dyno to at least check how accurate they are like they really should before they start tuning off them

Using elcheapo O2 sensors on a dyno as a sniffer is bad form on the tuners part and just to save a few dollars, a trade is only as good as his tools

My crappy Innovate LC1 worked perfectly for over 4 years, including track work. The same sensors are lasting perfectly well in OEM situations for many years. If the car manufacturers are fine with them, so am I. ;)

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I found that my idle screw was set in too far- would choke the engine when you remove IACV plug. So I disconnected TPS, IACV plugs and adjusted the screw out to idle (warm) at 800rpms as set on Powerfc without any electronic/ecu aid. After adjusting screw n re-connecting plugs back, checked base timing-was still at 20degs but feels right to drive, like it was before. No knock levels over 60, yes I do know the knock sensors arent reliable. And I bumped my TPS to show 0.45V at idle from 0.41V just to keep it at 'stock range'.

Heres my funny map traces

post-49401-14100717506173_thumb.jpgpost-49401-14100717655576_thumb.jpgpost-49401-14100717820722_thumb.jpg

The first two pics are a normal 30sec low rpm below 2500 drive in 1st n 2nd then a power pull in third revving out to 6.7-7k rpms.

Third pic is a pull in 1st, 2nd and 3rd

Edited by rondofj

I've read most of the content in this thread. Interestingly I am having somewhat similar issues with my car. It will get a little sloppy between gears until boost ramps up. Idle can also be retarded when the car is warm. My car is an R33, some similar parts but the one that has hit me the most so far is the f**king Gates timing belt.

I use one. Its a piece of shit. When I first installed it, it was noisy. I had to pull everything apart and tweak it. It still makes noise. I took it to a shop and they said this is why you do not use a gates belt. f**king piece of horse shit, I should have just went with the Nissan.

None the less my car is going to Unigroup this Thursday to rectify a misfire. I also need to eliminate the slop I've created in my tune by pulling timing to eliminate a ping.

Does anyone know if Unigroup are able to provide ECU's? If so I might get them to rip that f**king power fc and AFM out and give me the MAP goodness.

I love the PFC hating, I have one in my 32 and had one in my 34 and loved both of them and if they could do flex fuel it will still be in my 34, I sure I have said this before but will say it again, while near every tuner CAN TUNE a PFC very few know enough to do it properly :(

The first person that tuned my 32 didn't know and I hated it and wanted to swap it for anything else until I found Scott and after talking to him for 5 mins I let him tune it and never looked back, farkin excellent ECU, and in the 8 years it has been in my 32 it has never missed a beat

I have no issues with how the pfc works by all means both my cars run a poser fc. The issue for me was getting my tune to work with my new intake pipe correctly. I also wish they added the ability to give inputs. I would have loved to run flexfuel. The thing about newer ecus is they have higher resolution ignition and injection tables which can allow for a much more precise setup which can be felt on road while at cruise. Ive read only good things about unigroup and their ability to do the power fc but if i am able to get a new ecu to run a VE tune and leave the gates open for flexfuel then i would be a happy man.

Ron, have you actually matched the timing being displayed on the power fc in monitor mode to the timing you are setting yet? Like you are meant to. Or is 20 degrees just a random setting?

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