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

Me me me soldered joints inside , not new it was used.

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

Whats wrong with it? Its soldered inside those taped bits

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

My z32- and how its wired to neo wiring

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

My leaks were minor- tiny frothy bubbles, sealed now with new joiner and tightening, but apart from that, yes thats my experience with this frigging O2 sensor. Will a r33 NTK one fit? R34 one cost $100 more for a plug the only difference I think. Anyways the bov block plates gone and I've sanded the ground point at battery to chasis. At least theres a peace of mind that all these friggin areas /sensors of the car have been looked at/sorted.

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

I can tell you fellas one thing- switching off AND UNPLUGGING the O2 sensor in my car isn't a good idea at all (shit tune???!), it starts knocking with really high levels on the FIRST high boost pulls, and knocks at 5000rpms+ pretty early. Plug it back in and its all good, no knocks so far. And driving normally 60-80kmh, the O2 voltage fluctuates betwn 0.36-0.42ish volts, then after sometime it gets to the 0.68-0.76V range thats when it gets 'sticky', jerky, hesitating/ rough. So I will get a new bloody O2 sensor n be done with it. Cos O2 off dont work on my car too well to convince me.

Am going to fit new joiner where boost leak was, sand the ground point properly and remove the bov blockoff plate. And will look into a tailpipe wideband sensor/gauge.

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

Im suspecting the afm all along, its supposedly a genuine used z32 imported from the US, looks legit with orange sticker, mesh etc. Might post up pics later. Can you not block off the sensor element with a tab glued to the rear? So it reads one way only.

Got the boost leak tester out and found 3 more leaks at 14-19psi- 2 cooler joiners and one brake booster hose, its pretty minor, doesnt froth up hard from the soapy water, just very light frothing/tiny bubbles.

Set TPS back to 0.41V and got german Liquid Moly injector cleaner in the tank. Smells exactly like kerosene that I paid $16 /300ml for! Car still doesnt run right down low, doesnt sound and feel happy. Am not so worried about the power loss on shifting, moreso the running crap/no power, excessive fuel useage. O2 is disabled AND disconnected. What the hell could it be apart from afm? Intake pipe mod will come AFTER i solve this problem first,.

One thing I remember 3yrs ago without the z32 and 630ccs on a stock 208rwkw car I was still returning 16-17L/100kms. I had the 255l/hr Walbro pump/(with direct voltage feed) from that time. Now the economys shot up to 20-21L/100kms, and inconsistent unhappy car- was same with Nistune.

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

Ok so TPS will be adjusted back. One thing I can confirm my afm voltage always goes sky high usually 4.9+V under high boost/rpm - had to switch off the airflow warning check light in powerfc.

While at it, chuck a bottle o injector cleaner in the tank for peace of mind..

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

Well no I adjusted it after driving because I read it should be in the 0.45-0.5V range, if thats what it does then I should adjust it back to 0.41V?

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

650km.. Boy is that even possible. I struggle to get 250kms! Well I found that my dipstick doesnt actually smell of fuel, I was mistaken, but my fpr vacuum hose has a slight fuel smell, so will replace the fpr, the fuel damper vac hose is ok though. But then no fuel shoots out at idle and 2000-2500rpms with disconnected hose???? Is it possible that it only happens under boost at load?

Set the TPS to idle at 0.48V instead of 0.41, hard to get 0.45, its too sensitive. O2 sensor unplugged n switched off. My O2 voltage doesnt fluctuate with it connected at idle so its def shot.

I found that I have lost a lot of power when boosting since the last couple days and its started to get high knock levels 130-140 at 5000rpms in third which it WASNT doing before. AFM peaked at 4.955V, what could it be, I havent changed my setup but I did lose the grey TPS plug cap thats supposed to go to the auto transmission wire something (mines manual). So I have the brown n black TPS plugs connected but grey one just has wires running thru with the end cap lost, is this a bridging cap?? Knocking a sign of leaning out?

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

I still prefer to change it and keep it enabled as it was tuned with it - do any of the R34 NEO people use the r33 NGK O2 sensors with the plugs cut off and wires crimped together? NGK dont make a R34 one, rang em up. Else the universal PEC O2 sensor from Vulture Motorsport is what I got and its gone funny after just 3 years!

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

no worries mate will hit you up if need be, let me test a few other bits over a couple weekends - fuel reg, iron out boost leaks, earths, new O2 sensor etc; I have decided not to get the wideband cos of extra costs of equipment itself, weld bung away from turbine housing, touching up tune etc..

Do u guys get ur NGK O2 sensors from repco/autobarn/bursons etc?

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

The only way a fuel reg can dump fuel in manifold is through the vac/boost line, start car and pull line off and look, for enough fuel to cause these problems it will flow out at you

I have personally never seen a factory fuel reg go like that

thats exactly what I will be doing tomorrow morning - check for fuel in the reg and damper vacuum hoses. Hopefully I will find fuel and confirm a dead reg - can i use R33 reg on 34 /possibly wolverine's one or do I need a R34 one - wreckers or buy new? Hopefully no touch up tuning required, but how to check if its providing the req. fuel pressure under load - else it will lean out n go bang haha..

I do remember when DVS Jez had a go at my 'stock' car 3 years ago he mentioned the fuel pressure's playing funny and advised me to get a spare r34 reg, which I got thanks to Johnny, so the second time round I went up to Jez with the spare reg, we didnt end up fitting it cos it was alrite then.. Now I have to look for that little reg, dunno where I put it or if it still there lol..

And yes I use a stock 'crushed' bov like Ben C34 does.

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

Thanks, is it better to get new though, never know when the used ones let go- will check if I can use 33 one on a 34- i think the 34 neo has 2 dampers n 1 reg

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

Theres 2 bloody regs/dampers on a neo though

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

Well took off dipstick and can smell fuel big time. Will be taking off fuel pressure regulator vacuum hoses to look for fuel later. Stay tuned..this could be it, a leaking reg.

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

Yah man..doing my head in. Change the whole bloody engine man, put in a CA18DE. Much better mileage and powers not too bad..hah

Anyones a pic of a good intake with bov entry angle that has proved to work great?

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

I dont think I've ever got 300kms to my usual 50L fill-up, I'm generally in the 250kms range, dont think anyones done it worse? :S. I'm goin to get an O2 sensor - either an NGK/Bosch and see if the f*cker makes a difference. Maybe a Ford EL one.. And while at it, raise the TPS to 0.45V at idle from 0.41V and check/clean all earths including ECU one. And another boost leak test-basically try to pump 30psi through the mofo.

Last call would be the intake pipe bov entry mod - do I do it to existing pipe or get a new one made, might cost more

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

Stock. Why are some people still sayin to get a new O2 sensor when Im supposed to leave the O2 feedback off

? Sorry dont get this one.

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

^^^ That is highly possible, thanks for the suggestion, I'm definitely guna check that..

It does have all the signs of a stuffed fuel reg - excessive fuel use, fuel smell, oil out the exhaust (concrete survace behind exhaust has oil spray), no black smoke though. The vacuum hose from reg is guna be coming off to sniff for fuel there :S

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

OK,

So I return to this after quite a few posts, but based on most recent feedback from Ron and various of the replies since I see the following as being the most likely scenario.

1) Sudden pulse of AFM signal upward with consequent increase in ECU load signal up 5 or 6 cells definitely implies it's a reversion problem. Blocked BOV will of course cause that - and you have seen it occur with blocked BOV. Wrong BOV return design will also cause it, and you have seen it with the BOV connected. Therefore....

thats right seen it happen in both scenarios, with blocked bov though, seems to run smoother and better low down

2) BOV return is not right. The connection from the cam cover hose doesn't matter - only the angle of the BOV return does. I suggest further speculation on the cause of the hesitation problem should be put on hold until someone remakes the BOV return.

maybe I need to have my intake pipe bov entry angle modified - does anyone know a good fabricator in Sydney whos not expensive

3) High fuel consumption. As I see it your coolant temperature is 10 degrees too cold and that could easily cause the ECU to add a bunch of enrichment - especially if it was at the correct temperature while it was being tuned. This should be the work of 5 minutes for Yavuz to look into and report on what the ECU is doing. And to fix it might take only as much as another 5 minutes if it needs fixing in the tune or maybe 30 minutes if you need the thermostat changed.

Set water temp correction at 50C to 1.00 and 1.00 (low-hi loads)? Currently it is 1.04 and 1.07, and at 80C is 1.00 and 1.00 -- its only adding 4% and 7% more fuel at 50C though

4) High fuel consumption. The tank breather situation is a bit special on Neos anyway. The stock ECU has a whole bunch of maps (only recently uncovered and correctly identified by Matt at Nistune) around the emissions purge control logic. There is a solenoid valve that is only allowed to open under certain conditions to allow the vapours to be purged. If the PFC doesn't do this properly and/or there has been a physical f**k up of the system with various works (like FFP installations) then perhaps there is an avenue here for fuel consumption to go high. But I would imagine that if the ECU was properly running closed loop and most miles were done under cruisey closed loop conditions then it shouldn't be as bad as Ron reports.

My purge valve has 1 nozzle broken and the hose from intake plenum that connected to it has a block-off screw now. The other hose is removed (doesnt go to charcoal canister) Charcoal canister has that opening blocked off with a little hose and bolt and the other hose goes down to chasis along radiator and somehwhere - fuel tank vacuum? Any suggestions on this setup??

5) High fuel consumption. A f**ked O2 sensor will do this to you. Replace it or plan to live without it. Choose one.

Currently O2 is switched off in power fc but sensor still plugged - hence displaying changing voltage depending on throttle. Do I need a new sensor even with O2 switched off? Remember it doesnt hesitate at 1500-2000 and idle bounce with O2 off but rougher idle and runs a bit rough. And Yavuz did mention the sensor is going funny but not to worry...yet

As to Yavuz's statement of the load jump causing R&R - well, it's not R&R because there's no such thing in a PFC unless it is deliberately tuned that way (ie the tuner makes the top end of the maps as mentally retarded as Nissan did!). But I suppose functionally it is equivalent to R&R if those load cells add a lot of fuel and have less timing. Terminology doesn't really matter - I think we can be sure that it's a reversion problem and that you need to fix the reversion!

Is on cards now. But what do you guys think of a bad earth/ground as the car sometimes runs like a dream? 15-20% of the time really.

Please see my response in red above ^^^

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

If some one connect the vacumn line incorrectly on the pump, then you will get 20L/100kms cause instead of allowing only vapour from the tank to the manifold, raw fuel gets sucked thru

under vacumn conditions.

Who did the pump?

I did -3 years ago, and yeah economy has always been crap since a long long time, with the Nistune as well, dont know exactly since when. Good point - I didnt even know about the vacuum line just the fuel return and supply line - worth having a look.. What is this vacuum line and does it run from intake manifold?

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

If you were in Sydney then you do my pipe! haha..well I can't try out your pipe, no guarantees it would fit - its one of those 'on-site' jobs aye

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

I dont even know whos the fabricator lol.. And - this issue has only been happening with the recent switch to the powerfc this year.. The fact that the piping doesnt look convincingly bad has somewhat held me from doing it too..

And will this solve my intermittent rough running/ lack of power and 20-21L/100kms fuel economy? Don't think so

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

Mount Z32 on cooler piping like Stao did once? Not a fan of high boost blowing at the delicate sensor.. :S And screw changing ecu again - no farrkin way haha.... $2000 for pretty much no gain just hopefully no bogging down on gearchanges.

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

Yavuz saw it jump and thats when he was convinced theres a big problem- he said that its dumping fuel n retarding timing at that point.

Yesterday I unplugged the z32 and it wouldnt even start- just cough cough and die lol