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


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Monitor Mode:

The Commander can display up to 10 parameters of data in real time. Monitor Mode can display:

Engine RPM

Ignition Timing

Vehicle Speed

Air Flow Voltage (Pressure Sensor Voltage)

Injector Duty Cycle

Boost

Knocking Level

Battery Voltage

Intake Air Temp

Water Temp

i'm still convinced the powerfc changes ign timing in idle control circuit.

can confirm this (to a point, as I don't fully understand the whole logic pfc uses)

mine will show 22-24' timing on the controller during warm up,

But the timing map cells show 15' and 17' in the cells it idles on.

So- it must change timing during idle condition and warm up conditions.

Ecu's alter ignition timing to control the idle as it is quicker to react than opening a solenoid and waiting for the air to be sucked into the engine ( obviously also use that method)

  • Like 1

Cmon Ron. Hurry up and get your timing right so you can go back to not fixing the bov return.

haha. Actually this weekend I'm guna get a plastic coke bottle with lid, cut the top off, remove the bov return hose from the bov end and jam this lid up the hose's ass (lid side in). And let the bov vent to atmo, just to see if the 'reversion' happens then. The cas timing at the moment I think is possibly 1-2 degrees more advanced than before and boy it pulls so much better now esp in third - loving that shove, and no the motor ain't blowing up lol - even if it did, you probably wont hear of it.. :closedeyes:

Edited by rondofj

haha. Actually this weekend I'm guna get a plastic coke bottle with lid, cut the top off, remove the bov return hose from the bov end and jam this lid up the hose's ass (lid side in). And let the bov vent to atmo, just to see if the 'reversion' happens then. :closedeyes:

????

Yeah. Few more pages till this is sorted.....

At least you can enjoy a coke.

Edited by Ben C34

Ron.......it doesn't matter whether the AFM sees air flowing backward from the BOV going the wrong way, air coming back through the turbo (because of blocked BOV) or air being metered going forward because you've opened the BOV to atmosphere.......the AFM still sees air that the engine isn't breathing and the load cell will jump to the wrong place in the ECU and shit will happen. The shit might vary a bit. But it will still be shit.

  • Like 1

If you're having those issues, I would rather just vent the BOV and then setup the decel fuel recovery point a little higher..

^^ Done this. Coke top plug onto bov return hose and bov vented to atmo. First pic shows this - looks like the bov is connected to black hose but its not - theres clearance.

Result - no difference to massive power loss for 3-5 seconds during shifts (under load). As GTSBoy said earlier there's still air loss (thru atmo bov) thats been metered and not going into engine. Drive was same same even though I expected a bit of a difference. Didn't bother with adjusting fuel decel enrichment points. And its off now, bov plumbed back in as usual.

3rd n 4th pics show a normal map trace of a normal below 3000 rpms 10 min drive in metro areas (no boost), and one with 2X high boost pulls in 2nd and 3rd.

Last pic shows where my CAS sits currently.

Fuel economy hasn't changed - at half tank yesterday from full I had travelled 140kms. Metro areas only, 97% no boost driving with the occasional pull in 2nd and 3rd.

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post-49401-0-29609800-1409530616_thumb.jpg

post-49401-0-38299600-1409530620_thumb.jpg

post-49401-0-19621300-1409530626_thumb.jpg

Edited by rondofj

you need a wideband

Man you are such a wet blanket sometimes.

Can't you see Ron is having fun while learning by taking random guesses and messing with stuff randomly.

A wideband would just cost money and then instantly pay itself off once you factor in the time saved being wasted and worrying about stuff.

Ron is having fun. He loves it. Don't ruin it with useful tools that will speed up the fault finding.

But now the air is going blow past your thermostat and make it colder so it will never get up to temp... So you need a stronger spring.. >_> :unsure:

Edited by XGTRX

Something else I didnt mention - my exhaust always smells pig rich (part of the reason is that I have a hollow cat). No black/white smoke, just smells pig rich.

Wideband will spoil the fun, it will just tell me what I already know - that my car's running quite rich - and yeh it will tell me the AFRs at each point etc, which is handy.

So lets guess n play with random stuff, and blow it up if it has to. Wideband will come eventually. Lol

At what point do you start to look at the tune, when you run it where you think the Cas was does it have the hesitation between gears ? Is it possible that you have moved the Cas at some point and not returned it to its correct spot ? If so then it will need to be retuned :(

Having the BOV connected in away it causes reversion will cause more of a problem then having it vent atmo and this should show up on the hand controller AFM tracer, did you get someone to watch it will you made it do it which will require this been done with both setups, either is going to give you an unhappy spot in the tune but both will give different result in tracer

While the wideband will tell you some of what's going on so will a dyno run up, just it can be done safer on a dyno

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