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

[Dose Pipe Sutututu]

I don't think Ron wants to listen to our advice.

[Ben C34]

This thread rules

[rondofj]

Now we're going to Whitecastle ...

[rondofj]

Update so far- just replaced my O2 sensor with the NTK R33 sensor- cut off plug n crimp wires- works.

Pics- left one is stock R34 sensor when I bought car 4yrs ago and after a year of use.

Right one is the O2 sensor I replaced yesterday- as u can see running pig rich, also confirmed by spark plug pics earlier.

Havent test driven yet but dont expect massive improvements.

Lookin for a stock GTT fuel reg- wrecker wanted 50 bucks told him see ya later

All this to solve my loss of power, huge fuel use, bouncing idle( havent had bouncing idle in ages), inconsistent running sometimes, not much now though. Main issue is a fair bit of power/torque loss and fuel use- finding it not so easy to spin 2nd now as before- not that I want to.

The power loss at downshifts and also some upshifts is most possibly the bov entry angle and doesnt bother me for now till I get these other issues sorted.

Edited August 17, 2014 by rondofj

[rondofj]

From todays driving I can confirm that now theres absolutely NO bouncing idle and jerky/hesitation/roughness in the 1500-2000rpms band and idles possibly a wee bit smoother- this with new O2 sensor n feedback ON as recommended by Yavuz. The O2 voltage is also in the 0-0.1V band under idle and alternating quickly when driving as it should, generally in the 0.1-0.2V band during low rpm driving- previous shagged O2 sensor would always be at 0.5-0.7V(rich).

But I still have a dramatic power loss as from the last 3 weeks- boosts to 22psi but no power/hard to spin in 2nd even whereas before you could just stab so lightly and spin at will. Before it also used to rev a fair bit quicker, now not. Boost leaks have been tested twice and I've killed myself fixing these. Nothing else changed, base timings 15deg as checked/set with light off no1 plug n also confirmed by power fc readout. Havent touched any timing/fuel maps so cant be these.

So I suspect its still running rich - water temp goes to 76-78C as usual, once went to 81C on a hotter day. So where the hells my power gone?

Bloody AFM again? Buying a wideband in a week or two to check afrs then I dunno next step. Need to have my power back and the fuel economy back (will be tested now Ive replaced the O2) before fixing the bov entry which is the least of my concerns right now.

Edited August 17, 2014 by rondofj

[Badgaz]

well after you've checked everything electrical, time to start checking everything mechanical.

[rondofj]

Your right, would my carbon-fouled plugs be a big part of my power loss or is that more like a secondary thing to look at later?

[XKLABA]

That's more like a sign of the problem, what ever is causing your plugs to carbon up is what needs fixing

[Badgaz]

Your right, would my carbon-fouled plugs be a big part of my power loss or is that more like a secondary thing to look at later?

they didn't look too bad but as XKLABA says they are just a sign of the problem. would still love to see a youtube video of the perceived problem.

[rondofj]

Overfuelling. Both plugs n O2 sensor were fouled. O2 replaced. Temp sensor to ECU works n displays correct temps but not ideal - usu 76-78C this winter. I dont blame tune cos before the recent power loss it was running really great sometimes (only 25% of the time) but not all the time, but still overfuelling - poor fuel economy n fuel smell.

So what else can it be- AFM is all my little brain can think of..

Edited August 18, 2014 by rondofj

[Badgaz]

when you get your wideband kit do some logging....if its as rich as you say it is then you'll see 10's on the afr gauge.....the fact your map trace on your commander jumps cells still leads me to believe the AFM is a bit bung....

[rondofj]

Yeh I will do that. Could you explain the map trace a bit- theres the fuel n timing maps, both 20X20 cells. I assume the car can be at only one specific point at a time on both fuel/timing maps - eg row 3, column 10- means that it has to be row 3, column 10 on BOTH maps and this is what the map trace shows right? It shows that specific point (r3, c10).

My fuel map is shown in 'percent' values I think- the idle cells are generally 098,097,100 etc. I assume that this is a ratio of the stoich ratio 14.7:1 ie 098 is 14.7/0.98=15:1 AFR am I correct?

Edited August 18, 2014 by rondofj

[rondofj]

If thats the case that means I can see from the map trace what afrs its running by noting the cells then going to the inj map to check the afr of the cell? Tedious but

Edited August 18, 2014 by rondofj

[Dose Pipe Sutututu]

Won't be a correct way of reading it

[Badgaz]

It's one way to look at it but you need to know what correction values equate to lambda values or stoich. This can be done but is usually what your tuner will do when seeing your base fuel map. On the power fc 100 equals 100% of the stock value. There is another page where you set your injector correction factor. Like I said earlier if you can be bothered sending me your recorded values I can take a look for you.... To see if there aren't any blaring issues.

[rondofj]

Ok thanks I will try to write it all down n send to you soon when I get time

[Badgaz]

you can download the universal power fc-edit software off the web. download that and plug your values into that, might be better.....then you can just save the tune file and send me that.....but change your AFM first.

[rondofj]

Ive got my inj map on an excel file, will pdf n post when I get to work, do u need the timing map too?

[Badgaz]

Yeah that will help... It all will.

[rondofj]

See attached fuel n timing maps - seems like an unwanted 'wedge' in a part of the timing map (orange/ yellow)

Ron R34GTT Fuel Map.pdf

Ron R34GTT Timing Map.pdf