Jump to content
SAU Community

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


Recommended Posts

That's good news.

Shit tune confirmed ...... flame suit on.

Unless it's the mysterious gates timing belt ignition scatter issue.

Edited by Ben C34
  • Like 1

Im hoping its a shit tune- despite taking my car to Unigroup 3 times, they just couldnt fix that bogging down prob, they went over but didnt touch the tune which they claimed is as good as it can be, their after-service is good.

I still have my pink label R34afm which I wana test though to see if the z32s farked. And maybe test the pcv valve cos boost went to the crankcase oil vapor vent area. And change O2 sensor.

what about a worn harmonic balancer/ key if it was moving or loose down there wouldn't that give some of the symptoms?

Edited by AngryRB

Yeh I was meaning change the powerfc settings to r34 afm after putting that in. Harnonic balancer/keys fine, I inspected that/ did the timing belt myself.

You guys still dont reckon my O2s shot? Drives much better with it off. It must have been richening my car like a pig in the past.

Also dont understand how my dipstick was never blown off while driving all the time at 22psi but now with the boost leak test at 19-20psi it shot off like a rocket! Lol

Keep it disabled then

Even if you choose the right afm you'll be surprised it might not run properly. If the afm was again rescale your fuelling will be off

The stock map sensor isn't referenced by the PFC as I said yesterday. Turn 02 feedback off. Like I said yesterday, your fuel economy usually won't change a great deal with a Unigroup tune. A new sensor is cheap enough and can be replaced at your leisure.

The PFC handcontroller item BOST (or whatever it is listed as) is for when you are using the Apexi boost controller IIRC.

What doesn't make sense is that you mentioned that you car was pinging...a rich environment won't cause it. There is something that isn't right with your ignition timing, I think. When it pings or idles crap is your engine noisey, like a belt shutter, noise, or something else. Sorry but what you are describing doesn't make sense.

A shame u don't live in nzwould have the datalogit plugged in and checked by now.... I'm beginning to suspect tune. Did they do your accelerator pump corrections if they were left stock it will go mega rich on gear changes.... Mine was going to the 9s before i tuned it out.

Thanks mate, so I will leave the O2 feedback off till I get new O2 sensor (I know irts preferrable not to have O2 enabled but my car was tuned with it, so its best I leave it ON? Or not, and heres my accelerator pump enrichment that you asked about, do the adjustments look ok?

post-49401-14070699620295_thumb.jpg

The O2 sensor should only be fine tuning the mixtures. It should be tuned woth it off to give the correct mixture, then turned on and checked after the tune is complete. It should barely make a difference on a properly tuned car whether off or on, especially immediately after being tuned.

Again, refer to your tuner. Ask him. He tuned it. We are guessing. It should be running 14.7 at cruise (pretty much) with or without the sensor. Which it doesn't seem to be due to your consumption.

i run my car with the o2 turned off permanently. those injector settings looks like stock settings. mine are attached but are for 850cc injectors....but they still make it fairly rich.

starting to sound like your tune didn't take everything into account. e.g wot & cruise only.

post-95424-0-06314800-1407103084.jpg

turn off your O2 feedback, better yet just disconnect it.

Tuners always turn it off when they are tuning to disable the trims.

as for your acceleration enrichment, just set it low and work your way up till the car stop buckling.. sometimes it worth adding in more decay.

you have to adjust these like any fuel trims with a wide band. you can log and see the effect of enrichment when lift off and mashing the pedal, this is what a tuner would do if they are doing a complete tune.

yeah different AFM different turbo = different values required

just write it all down, and start decreasing it for the RPM affected.. might actually reduce your buckling

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Thanks, I removed the fuse and the relay from the car and made my own circuit with them to test them with a test bulb.  I will look for the wiring diagram and go from there.
    • Jdm DC2R is also nice for a FF car compared to the regular hatches of the time.
    • Now that the break-in period for both clutch and transmission is nearly over I'd like to give some tips before I forget about everything that happened, also for anyone searching up how to do this job in the future: You will need at least 6 ton jack stands at full extension. I would go as far as to say maybe consider 12 ton jack stands because the height of the transmission + the Harbor Freight hydraulic platform-style transmission jack was enough that it was an absolute PITA getting the transmission out from under the car and back in. The top edge of the bellhousing wants to contact the subframe and oil pan and if you're doing this on the floor forget about trying to lift this transmission off the ground and onto a transmission jack from under the car. Also do not try to use a scissor jack transmission lift. You have to rotate the damn thing in-place on the transmission jack which is hard enough with an adjustable platform and a transmission cradle that will mostly keep the transmission from rolling off the jack but on a scissor lift with a tiny non-adjustable platform? Forget it. Use penetrating oil on the driveshaft bolts. I highly recommend getting a thin 6 point combination (box end + open end) wrench for both the rear driveshaft and front driveshaft and a wrench extension. These bolts are on tight with very little space to work with and those two things together made a massive difference. Even a high torque impact wrench is just the wrong tool for the job here and didn't do what I needed it to do. If your starter bolts aren't seized in place for whatever reason you can in fact snake in a 3/8 inch ratchet + 6 point standard chrome socket up in there and "just" remove the bolts for the starter. Or at least I could. It is entirely by feel, you can barely fit it in, you can barely turn the stupid ratchet, but it is possible. Pull the front pipe/downpipe before you attempt to remove the transmission. In theory you don't have to, in practice just do it.  When pulling the transmission on the way out you don't have to undo all the bolts holding the rear driveshaft to the chassis like the center support bearing and the rear tunnel reinforcement bar but putting the transmission back in I highly recommend doing this because it will let you raise the transmission without constantly dealing with the driveshaft interfering in one way or another. I undid the bottom of the engine mount but I honestly don't know that it helped anything. If you do this make sure you put a towel on the back of the valve cover to keep the engine from smashing all the pipes on the firewall. Once the transmission has been pulled back far enough to clear the dowels you need to twist it in place clockwise if you're sitting behind the transmission. This will rotate the starter down towards the ground. The starter bump seems like it might clear if you twist the transmission the other way but it definitely won't. I have scraped the shit out of my transmission tunnel trying so learn from my mistake. You will need a center punch and an appropriate size drill bit and screw to pull the rear main seal. Then use vice grips and preferably a slide hammer attachment for those vice grips to yank the seal out. Do not let the drill or screw contact any part of the crank and clean the engine carefully after removing the seal to avoid getting metal fragments into the engine. I used a Slide Hammer and Bearing Puller Set, 5 Piece from Harbor Freight to pull the old pilot bearing. The "wet paper towel" trick sucked and just got dirty clutch water everywhere. Buy the tool or borrow it from a friend and save yourself the pain. It comes right out. Mine was very worn compared to the new one and it was starting to show cracks. Soak it in engine oil for a day in case yours has lost all of the oil to the plastic bag it comes in. You may be tempted to get the Nismo aftermarket pilot bearing but local mechanics have told me that they fail prematurely and if they do fail they do far more damage than a failed OEM pilot bushing. I mentioned this before but the Super Coppermix Twin clutch friction disks are in fact directional. The subtle coning of the fingers in both cases should be facing towards the center of the hub. So the coning on the rearmost disk closest to the pressure plate should go towards the engine, and the one closest to the flywheel should be flipped the other way. Otherwise when you torque down the pressure plate it will be warped and if you attempt to drive it like this it will make a very nasty grinding noise. Also, there is in fact an orientation to the washers for the pressure plate if you don't want to damage the anodizing. Rounded side of the washer faces the pressure plate. The flat side faces the bolt head. Pulling the transmission from the transfer case you need to be extremely careful with the shift cover plate. This part is discontinued. Try your best to avoid damaging the mating surfaces or breaking the pry points. I used a dead blow rubber hammer after removing the bolts to smack it sideways to slide it off the RTV the previous mechanic applied. I recommend using gasket dressing on the OEM paper gasket to try and keep the ATF from leaking out of that surface which seems to be a perpetual problem. Undoing the shifter rod end is an absolute PITA. Get a set of roll pin punches. Those are mandatory for this. Also I strongly, strongly recommend getting a palm nailer that will fit your roll pin punch. Also, put a clean (emphasis on clean) towel wrapped around the back end of the roll pin to keep it from shooting into the transfer case so you can spend a good hour or two with a magnet on a stick getting it out. Do not damage the shifter rod end either because those are discontinued as well. Do not use aftermarket flywheel bolts. Or if you do, make sure they are exactly the same dimensions as OEM before you go to install them. I have seen people mention that they got the wrong bolts and it meant having to do the job again. High torque impact wrench makes removal easy. I used some combination of a pry bar and flathead screwdriver to keep the flywheel from turning but consider just buying a proper flywheel lock instead. Just buy the OS Giken clutch alignment tool from RHDJapan. I hated the plastic alignment tool and you will never be confident this thing will work as intended. Don't forget to install the Nismo provided clutch fork boot. Otherwise it will make unearthly noises when you press the clutch pedal as it says on the little installation sheet in Japanese. Also, on both initial disassembly and assembly you must follow torque sequence for the pressure plate bolts. For some reason the Nismo directions tell you to put in the smaller 3 bolts last. I would not do this. Fully insert and thread those bolts to the end first, then tighten the other larger pressure plate bolts according to torque sequence. Then at the end you can also torque these 3 smaller bolts. Doing it the other way can cause these bolts to bind and the whole thing won't fit as it should. Hope this helps someone out there.
×
×
  • Create New...