Help: KR when starting from a stop!
Originally Posted by BADSZ28
Well I tried the new tune with pulled timing and still get the KR. Does seem better though.
Next stop, race gas and pullin the valve covers to check for issues.
Any other ideas where this could come from?
I was just running a tune with advance hovering in the upper to mid teens in the trouble areas so I like to think its not a spark issue.
I'm just worried there's something SERIOUSLY wrong with my build causing this and I'm not sure where to start.
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From: NW Chicago Subs
I drove the car today and it still does it. Feels better in the low range though so I do think my timing was too high there. But I still think something else is causing this. Any A4 cars get this type of issues? I really think it is the clutch engaging causing false KR. Anyone know how to get around this without turning down the sensors?
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From: NW Chicago Subs
SSpDmon: What should timing be at idle for a cammed car do you feel? I noticed my timing is set pretty high (30*) for idle which is much lower than the lower part of the timing table. I wonder if I am getting KR due to the transition from the idle table to the timing table since it drops so far and there is little time to adjust or something like that.
I have this issue when my car has the M6 in it. With the TH400 it does not too this.
Clutch chatter. I can hear it quite well. I have always assumed it was that. My car did it from stops and when performing any 1->3 or 1->4 shift.
Clutch chatter. I can hear it quite well. I have always assumed it was that. My car did it from stops and when performing any 1->3 or 1->4 shift.
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From: NW Chicago Subs
Update: After the advice from SSpdDmon the car idles MUCH better, drivability is MUCH better and the KR has reduced to 2-4* vs. as much as 15* before. So improvements have been made, but still needs work.
Another question; what should AFR (O2s and ratio please) and airflow be at idle durring cold starts or when at op temp? Smells way rich?
Another question; what should AFR (O2s and ratio please) and airflow be at idle durring cold starts or when at op temp? Smells way rich?
To me this looks more like a mixture problem at tip-in, you
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
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Originally Posted by jimmyblue
To me this looks more like a mixture problem at tip-in, you
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
Thread Starter
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From: NW Chicago Subs
Originally Posted by jimmyblue
To me this looks more like a mixture problem at tip-in, you
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
see the O2s bottoming instantly and then switching but no
switching at all and stuck rich at idle with constant STFT
creep. It's trying to fix itself but never seems to get there
and every time you pop between cells, you start over from
zero (which is evidently not the right answer).
I'd concentrate on the low RPM, airflow and fueling end of it
and see if the spark situation fixes itself.
Launching!
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From: nj, edison
kr i would tweak the maf but only in the idle rpm range and a tad above that, kr is due to too much timing and or not enough fuel or a bit of both. if you have 28lb inj. and a 346 your milliseconds should be around .300 -.320 fluictuation will depend on the lsa of your cam. my cam is a baby cam .525 112 218/228. i had kr in the biggining but only in the low load eng. rpm ranges between say 0% to like 23% tps, timing helped a bit but adding fuel via the maf was what did away with the kr. you want as much timing as you can get for fuel economy it a combination of both fuel/timing. checking your plugs is the absolute sure way to know if you're running lean at idle and low load eng. rpm ranges. good luck
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From: NW Chicago Subs
Update:
OK so I got the WBO2 in. Seams it is indeed going flat lean on leaving from a light. Also, car seams to run better with the AC on so I will have to compare tables there too. Any ideas on how to get this thing to have more fuel from a stop? So I think once I get the fuel inline, I can give it more timing down low as it seams weaker now than before and I feel I removed too much timing.
OK so I got the WBO2 in. Seams it is indeed going flat lean on leaving from a light. Also, car seams to run better with the AC on so I will have to compare tables there too. Any ideas on how to get this thing to have more fuel from a stop? So I think once I get the fuel inline, I can give it more timing down low as it seams weaker now than before and I feel I removed too much timing.
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From: NW Chicago Subs
That is the range it is knocking at. I will check that. Seams like my tuner did not due much with the tune under 3k. It does idle better though with the lowerred timing.
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From: NW Chicago Subs
OK, after some logging, I am flat confused. Under the same conditions at speed, the car has no KR, but the same conditions from a stop there is KR. WHat gives? So if I go and change the VE or MAF, then it will change for both driving conditions, making at speed more rich wen it is just fine. I did add about 10% in the MAF in the area I have been having issues. Well the lower end of it. Still KR. I am affraid to keep adding due to adding fuel when it does not need it. I guess I will try climing further up the MAF table to see what that does. Or maybe just adjust the VE. I need to do more logging though. LTFTs were off. DOH!.
Adding arbitrary numbers to the MAF/VE isn't going to get you anywhere fast (unless you're beyond lucky). If it's just during transitional throttle, try playing with the burst knock settings at the lower RPM. If you increase the duration from the factory 3 turns of the crank to something like 50, drop the decay rate down to .15 from .25, and make sure the delta is something like .02 grams/cyl for less than 2000RPM, you can temporarily remove the timing based on what's in the burst knock table. That way, you can have full timing and the correct AFR at speed....but, less timing for transition. 
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From: NW Chicago Subs
Well I think there is some thought into it. I watch Hz and look where it is at when there is KR and added fuel there. But I will also try the burst knock thing.
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From: NW Chicago Subs
After watching the WB and some more logging I feel this is more of a throttle responce issue. I was reading a thread this thread (CLICK HERE) it seams I have been looking in all the wrong places. Now where should I look for throttle responce tuning? I tried making changes to the cylinder charge temp filter table. So far I have added 5% to the trouble spots but still doing this. Not enough logging to tell if it has reduced yet though. Any other ideas?