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Old 2nd August 2011, 02:06 PM   #21 (permalink)
leeroy_25 is Chuffed to nuts the RB30 lives!
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Thanks for that reply chris..
I think it is quite possibly either lean or rich but was not sure which way to go.. I added a bit in from about 88% -90% on the commander and it seems to help a bit but I am not sure how much I should or should not be adding!? Can I go up to say 100%? I would point out the next cells along for low load driving are quite a bit different.. they are around 107%.. and looking at a stock map I gather these would normally be a touch leaner if anything? Equally these could be too rich? But the car cruises along very happily on them..
The map has seen quite a lot of change up and down so it doesn't surprise me there are a few inconsistencies. Just need to spend a little time tweaking which I why I wanted a stock map to try and compare rough changes in the various load and rpm cells.
Maybe I will bung a bit more fuel on for idle on the way home and see what happens.
I am not yet convinced I don't have a weak spark or dodgy injector for a couple of reasons but will try this first.

Thanks again
Lee
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Old 2nd August 2011, 03:59 PM   #22 (permalink)
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U don't have a wideband dude or u can't get a Hold of one ? Or a datalogit ? Just have a play about and see if it idles smoother u won't do any damage at idle unless it's mega rich
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Old 2nd August 2011, 07:25 PM   #23 (permalink)
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I'm not sure how the Apexi ECU works, but the nissan unit runs the engine like a pair of 3 cylinder engines. Meaning that AFM and O2 feedbacks run 3 cylinders each. Thus measuring your combined AFR will not always pinpoint an issue.
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Old 2nd August 2011, 08:53 PM   #24 (permalink)
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Okay guy's so I had a play and think I might be getting somewhere.. I richened it up cold and it ran like shit! Leaned it back down a touch and it was much better a little fluffy but I didn't spend too long messing. Then when I got home and it was hot it was sounding a bit fluffy again.
I switched off and went in and was chatting to my old man about it for a few minutes and asked him to come and listen. Jumped in and the car wouldn't start.. kept turning over and not firing! This has happened before when it was previously on stock MAF's and first mapped!?
By now it would be worth pointing out the inlet air temp was reading around 51degs! Maybe fuel evaporating due to inlet temp?
So I thought I would try and richen it right up again.
Turned the key and viola! Idling almost spot on. Again I didn't play too much. it tends to rise up 50rpm if you leave it sat for 30secs or so but other than that a lot smoother.

I think/hope the issue is to do with the airtemp correction values. Because My filters are so crammed in when you are moving slowly the air temp easily hits high 40's and runs low 40's most of the time. maybe a bit less if cruising on the motorway. When we were mapping we kept having an issue that the car was getting richer after each run (I guessed it was due to the temp correction) sure enough we put the temp correction up so it would effect anything until over 50degs and had no more problems. but I guess now the car needs that correction under normal running and idle and is not getting it?

So we will see. I am going back to my tuner Saturday with luck and will get him to reset the air temp correction values and go out on the road with a wideband to tune it more in some free flowing air and to some more normal driving scenarios and will see what happens!
Ten I can try it on the dyno later.

R32 Combat do keep us posted with yours.. I am not 100% I have solved it yet!

I will most likely pull the plugs again and check them carefully just in case before I go on Saturday. Last couple of times I pulled them I noticed no'2 was wet with fuel both times and all the others were dry. This could be coincidence or could be another potential cause so I want to check that out?
Is a plug normally likely to be wet when you pull them I guess at the point you switch off one cylinder would have fuel in and then not fire so that seems reasonable? Thoughts on that please.

Will also make a note to check the MAF voltages are reading the same for 1 and 2. Good pint R32.. I tin the Apexi works in the same way? O2 readings seem pretty even once it's al warmed up.. but I have switched them back off as they made no difference!

Sorry for the long post!!

Cheers
Lee
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Old 2nd August 2011, 08:56 PM   #25 (permalink)
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sounding good mate,lets hope thats it
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Old 2nd August 2011, 09:01 PM   #26 (permalink)
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My GTR doesn't start sometimes. I have to stop cranking and then try again and it catches straight away. All since this issue started.
Very similar issues. I can't get my O2 sensor out, so I've getting a beefed up tool for the job. Hopefully i'll get it fitted tomorrow evening.
My AIT sensor works OK, and the correction values will be standard so for me, thats not likely to be the issue.
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Old 2nd August 2011, 09:29 PM   #27 (permalink)
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Presuming you have a new O2 sensor cut the plug off and use a normal long reach socket. That or put a jubilee clip around the O2 sensor socket once it's over the plug wire. Will stop the socket spreading open..

Very curious though! Cannot be O2 for me as they are off...

Could be MAF related if it is not indeed my fuelling or could be lack of spark?

Is there a way to measure voltage into and out of the ignition pack? I am guessing there should be at least 12v in and back out?

Likewise can you measure the voltage going into the coil packs? I assume volts coming out is not a good plan?!

Lee
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Old 2nd August 2011, 09:42 PM   #28 (permalink)
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Quote:
Originally Posted by leeroy_25 View Post
Presuming you have a new O2 sensor cut the plug off and use a normal long reach socket. That or put a jubilee clip around the O2 sensor socket once it's over the plug wire. Will stop the socket spreading open..
I will be using a deep socket as you suggest.

You can test the ignition amplifier and coils as per the workshop manual.
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Old 2nd August 2011, 10:05 PM   #29 (permalink)
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Thanks I will look those tests up.

Lee
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Old 6th August 2011, 06:06 PM   #30 (permalink)
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Any news R32Combat?

I went and did some road mapping today to tidy up my map generally and while we were doing so we checked AFR's on idle and tried to clean that up. Still cannot get a clean 5 all the time.. Sometimes it's okay and then it will start to fluff about a bit!? Richer is definitely better.. Ended up with idle AFR of around 13.5 to get it somewhere nice ish.

I am going to try another ignition amp next week and possibly some coil packs if I can find some to borrow.

Also going to check the cam timing hasn't moved .. I very much doubt but I remember when we were altering it the idle started to get a bit rough so we tweaked it back a touch.. but could be it was really rich then and now it's been leaned out some more it's gone a bit messy again?

If it is the cam setup then I will be stuck with it unless maybe I make it really rich on idle??

Keep me update with you problem and anyone got any other ideas I would love to know!

Lee
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Old 7th August 2011, 06:24 PM   #31 (permalink)
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How old are your injectors? Sounds to me like one is leaking a bit or have a bad spray pattern. That will give you idle issues.
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Old 7th August 2011, 06:34 PM   #32 (permalink)
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Double post
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Old 8th August 2011, 01:49 PM   #33 (permalink)
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Hi Swobber... It is something I considered.. They were secondhand but flow tested and cleaned prior to use.
My tuner also checked the other day to see what happened on idle if you cut the injectors right down to like 25% one at a time and as far as could be told they all had exactly the same effect.. Maybe not a fool proof test but certainly didn't throw up anything obvious.

Cheers
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Old 8th August 2011, 04:15 PM   #34 (permalink)
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Okay if it was me, id take the number 2 injector and swap with one of the others, since you have noticed that the sparkplug is wet on that cylinder. Then give it a run to see if it moves the problem to another cylinder. You could do the same with the coilpacks. Even the sparkplug could be the issue.
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Old 8th August 2011, 09:05 PM   #35 (permalink)
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I have pulled the plugs twice since noticing #2 being wet and it has not been wet again.. I also cleaned the earths for the ignition amp and coil packs and swapped the plugs this weekend. plus had the AFR's checked and redone at idle and of load. Car seems a lot happier the last time I drove it. Will monitor it and if it still play's up then I think first of all I will look at swapping the injectors around if there is any sign of #2 being wet again. I guess I could try taking injector duty down to 0 on #2 to make sure the cylinder completely cuts and if it doesn't and it does for any other cylinder then that could pinpoint the issue?
As I said my tuner took each one down to 30% and by ear the difference was the same on all.

Thank you for the advice

Lee
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Old 8th August 2011, 09:59 PM   #36 (permalink)
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when you had it tuned did you put a new timing belt on, in the first couple thousand miles it stretches quite a bit and can lead to idle timing being a bit off giving a "lumpy" idle sound
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