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

[rondofj]

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

[Kanaric]

I have the same symptoms in my R32.

Would drive normally like 90% of the time, then occastionally would lose all power at 3000+rpm. Off and on, i would get power 1 second, lose all the next. Sometimes on and off repeat. Then I would sit in lower rpms for a bit and it would drive fine.

Now it is far worse. Diring a drive around town it will cut all power above 3000 and not let me rev above it, then it would allow me again only to cut all power again as if i completely let off the throttle and then it would stall out going 40mph losing all power steering and power brakes with it which led to a serious oh shit! moment.

I'm fairly certain it's the AFM. I accidently drove the car around with it unplugged once and it drove exactly the same way. Wouldn't rev above 3000 rpm etc. When the car would work it was working fine, I did 4 laps on a track with it when it was a minor issue without it happening once so i'm fairly certain it's not fuel pump, coils, or anything of that nature.

Edited August 9, 2014 by Kanaric

[rondofj]

My car wouldnt even idle with AFM unplugged- how can some of u drive without one?

[GTSBoy]

My car wouldnt even idle with AFM unplugged- how can some of u drive without one?

It's a limp mode.

[XKLABA]

He has stock ECU you have powerFC

[rondofj]

Condition of plugs from cyl 1,2 & 5, also see the top of cylinders where they sit. Doesnt seem to be running too rich (black) or too lean (white) ie the plugs, but maybe a bit on the rich side?

[rondofj]

More bov entry angle/intake pipe pics for you fellas, dont look too bad hey..

Scotty, GTSBoy, Johhny..will be changed nws, but last thing after all else

Edited August 10, 2014 by rondofj

[GTSBoy]

That angle is pretty much the same as the stock angle (seeing as the steel return pipe and rubber is the stock one, you'd expect so), but I think that doesn't work too well when you get rid of the convoluted inlet elbow. Smooth inlet pipe seems to demand a steeper return angle, more towards the compressor. As most advice on here has already said.

[rondofj]

So my 1 channel monitor (ign timing) shows that normal 40-60,80km/h street driving under 3k rpms sees the timing move in the region 20-40 ish, depending on revs/load; high boost/high rpm n crazy speeds sees very low timing going down to 10ish, definitely 10s. Shifting UP the timing will drop to 10,15 etc for a second when shifting/releasing throttle. Shifting DOWN sees the timing go UP to high 40s, (highest 48) for a second before normalising in the 20-30 band. Is this why I feel the laaaaag/power loss, do other areas of timing sound right??

[XGTRX]

This may be a stupid question but did all these issues exist when you took it off your tuner?

Are you running the same boost level that it has been tuned for?. Did your tuner know of the knocking problem? What you are describing does not make sense at all.

[Dose Pipe Sutututu]

No timing is normal please don't fuark around with it if you've got zero idea

[Badgaz]

if you are keen....type all your fuel and ign map out in excel, 3d graph it.

[rondofj]

When I took it to tuner it had Nistune so no bogging down under downshifts/load, no bouncing idle, no stickiness' at 1500-2000, but yes all other probs- it was very thirsty and intermittent ly running rough/crap now n then long before that. Same boost. And yes absolutely NO knocking over 20-30 with O2 sensor plugged in and feedback enabled. Yesterday the intake was really really hot with O2 unplugged thats why it knocked I think. Possibly running too lean

[XGTRX]

Only recommendation I have is if you want to manage it yourself is buy a afr kit for $200 that way you know exactly what your mixtures are, and also log a real-time graph on your ignition to see if there is variance when it is on boost. Knock sensors are good but not perfect and if you have a noisy gates belt or cam/bearing type noise it could be triggering knock or you could be detonating and not hearing it. Your tune maybe out because you had it tuned with boost leaks and now it is running lean at wot but dumps fuel when off throttle because of the reverberation problem. Or the gates belt is causing variance in timing, might have to do the aem mod to the cas to stabilise timing. So many things it could be. Maybe get an afr kit and see how it reads.

Or maybe bring it back to your tuner.

Edited August 11, 2014 by XGTRX

[rondofj]

One thing is if you downshift and dont suddenly give it load, ie doubleshift/doubleclutch or wait a second or two before engaging the clutch the car wont bog down and lose power like it normally does., it will hook up well n go.

[AngryRB]

so you have a dodgy AFM by looks of it, your OEM coils were cheap, your BOV returns on the wrong angle, you have leaks and using a gates timing belt.

Its no surprise that it doesn't run perfect, best just to buy the stuff quality and new to avoid all this stuff around with it,

Edited August 11, 2014 by AngryRB

[XGTRX]

One thing is if you downshift and dont suddenly give it load, ie doubleshift/doubleclutch or wait a second or two before engaging the clutch the car wont bog down and lose power like it normally does., it will hook up well n go.

Reverberation issue, that's why I assume.

[XKLABA]

Double clutching a syncro box is something they do in movies, do it in real life and you will destroy your syncros, double clutching is for dog boxes only and also the slowest way of shifting

[rondofj]

so you have a dodgy AFM by looks of it, your OEM coils were cheap, your BOV returns on the wrong angle, you have leaks and using a gates timing belt.

Its no surprise that it doesn't run perfect, best just to buy the stuff quality and new to avoid all this stuff around with it,

That comments half retarded and maybe sarcastic. What is dodgy about my afm, its not a fake z32, my coils being cheap dont mean its not legit, although thats possible (car dont have symptoms of bad coils does it?!). It was n still is advertised as genuine nissan OEM items. As for leaks, everyones got some and mines largely sorted. And I dont have issues with my Gates belt, most people run one dont they, and I would use one again! So that just leaves the bov entry...

[CEF33Y]

Double clutching a syncro box is something they do in movies, do it in real life and you will destroy your syncros, double clutching is for dog boxes only and also the slowest way of shifting

So you mean granny shifting, not double clutching like you should, isn't real?

Dang.

But on topic, I'd change the return point for the bov. Im actually in the process of putting a stock bov on my cefiro, and Mark (unigroup) said to be carefull how I plumb it in, and pretty much said point it directly at the turbo.

Broken record I know, but its worth a shot yes?

As for you fuel economy, are you thrashing it everywhere? cause 250km to a tank is shocking.

I've got the 02 turned off, doesnt affect the on boost performance and I easliy get 400 -450km to a tank