AFR pegs lean when trying to get going..

aaronjb · August 8, 2008, 20:24

Well, after going over it all again tonight;

Cleaned and checked the KrankVents - they're operating fine (only let air past in one direction - OUT of the rocker cover).
Catch can hasn't sprung a leak.

PCV valve is fubarred, though - the little spring inside it appears to be loose and wobbling around.

So I put it all back together but with the line that would normally go to the PCV valve blocked off at the intake manifold - properly blocked off this time.

Went out for a drive and;

When stone cold it was OK
As it warmed up lean spots started appearing all over the MAP - low throttle incidence and ~2500-3500rpm goes 15-17:1
Once it was fully warm and I parked up at home and it was idling fine.. Suddenly the AFR starts swinging between 12.5:1 and 17:1 - revs are stable, can't hear a vacuum leak anywhere, but the AFR is wandering all over the fucking shop.

So, Mark, suffice to say I won't be there tomorrow - I just don't trust the car at all anymore, not enough to drive around the block, let alone drive up to yours..

I think I'll be car shopping this weekend s:evil: :evil: s:evil:

markiii · August 8, 2008, 20:44

have you recalibrated the wideband?

so not even good enough to limp over bugger s:? :? s:?

aaronjb · August 8, 2008, 20:48

Yup, I recalibrated it before I started the car (seeing as the car had been off for a few days)

I guess there's a chance that's faulty as well - but it's definitely going lean at points in the map as you can feel the car pull back (you can't tell at idle, though). Maybe an injector is going out, that would explain the AFR at idle.

markiii · August 8, 2008, 20:49

well I have spare wideband, intake manifold e.t.c at mine spoke to stu if you can limp it over to mine we can spend teh day sorting yours?

VVT-i · August 8, 2008, 22:04

I noticed mine was running a little rough so had a check and found a vacuum leak.. the car was running lean on idle too and gave me a cel, CEL = too lean, can't recall the code sorry.. I found the leak and and re-attached the hose that had popped off, disconnected the battery to reset the light.

When I restarted the car it ran a little rich at 1st then went lean.. after a very short time it was still a little lean on idle, maybe around the 16 mark, as I raised the revs it sat at what it normally sat at.. fluctuating between 14.2 and 15.5 or there abouts.. I took the car for a drive and it drove fine, the AFR read as normal until it was left to Idle then it went lean and the CEL came back, I reset things again and got the same thing, OK for a while the the light on idle. I figured that as I was disconnecting the battery to reset the light that the car had to start from scratch to re-learn and this was possibly why it kept going back lean at idle, so I decided to leave it idling for a little while occasional touching the fast pedal.. after around 20 minutes the AFR krept back to it's normal 14.2 - 15.5 pulsing and when driving it sat around the same. Under boost it goes rich and when decelerating it shoes lean (02 sometimes).. as normal. Although I still have the CEL (not had a chance to get it reset properly without disconnecting the battery) the car drives normally, sounds normal and the AFR behaves normally.

I had also calibrated the wideband and I cleaned the MAF too.

SimonC_Here · August 9, 2008, 08:26

Quote from: "markiii"well I have spare wideband, intake manifold e.t.c at mine spoke to stu if you can limp it over to mine we can spend the day sorting yours?

I think your wideband is in my cupboard actually Mark.
I could drop it off at Aarons though if he needs it.

Simon

markiii · August 9, 2008, 09:13

bugger must get that back from you soon, may as well drop it to aaron if you see him first

DAZ400 · August 9, 2008, 17:55

I had a problem once very intermitent, car was driving fine then every so often when hot it would just go lean, never did get to the end of it, but i had an air air intercooler which was hacked quite considerably to get it to fit in the bay because of the extra space of the smt hydrolics. i have now removed it and re plumbed everything with new pipes and seems ok but only drove it a couple of times as the car is off the road in storage no mot or tax.

perry's car that had the engine blow up after the PE turbo fit was done to a faulty injector on cylinder 3 although he did not know it was lean as at this time he never had a afr guage.

it is very frustrating when you have a problem especially an intermitent one, i can only hope you find the problem, you have my sympathy.

by the way i have a standard feul pump spare as i have a performance one fitted.

Cheers

Darren.

ChrisGB · August 9, 2008, 18:56

Quote from: "aaronjb"Yup, I recalibrated it before I started the car (seeing as the car had been off for a few days)

I guess there's a chance that's faulty as well - but it's definitely going lean at points in the map as you can feel the car pull back (you can't tell at idle, though). Maybe an injector is going out, that would explain the AFR at idle.

Hi Aaron

I am clutching at straws now:

As the car runs in open loop mode all the time, only the CPS, MAF, IAT and TPS are providing fuelling information to the ECU. You have eliminated the MAF and IAT sources already. Any chance that the TPS output is intermittently dropping, thus telling the engine that the load condition is low? It is possible to log TPS vs AFR? I think that the CPS is out as a cause. If it were intermittent, the timing would be shot.

Long shot, but worth a try.

Chris

Anonymous · August 9, 2008, 23:28

Quote from: "aaronjb"Well, after going over it all again tonight;

Cleaned and checked the KrankVents - they're operating fine (only let air past in one direction - OUT of the rocker cover).
Catch can hasn't sprung a leak.

PCV valve is fubarred, though - the little spring inside it appears to be loose and wobbling around.

So I put it all back together but with the line that would normally go to the PCV valve blocked off at the intake manifold - properly blocked off this time.

Went out for a drive and;

When stone cold it was OK
As it warmed up lean spots started appearing all over the MAP - low throttle incidence and ~2500-3500rpm goes 15-17:1
Once it was fully warm and I parked up at home and it was idling fine.. Suddenly the AFR starts swinging between 12.5:1 and 17:1 - revs are stable, can't hear a vacuum leak anywhere, but the AFR is wandering all over the f*****g shop.

So, Mark, suffice to say I won't be there tomorrow - I just don't trust the car at all anymore, not enough to drive around the block, let alone drive up to yours..

I think I'll be car shopping this weekend s:evil: :evil: s:evil:

You ID'ed the problem, but didn't actually fix it. After fixing (replacing PCV valve), it will probably be back to normal, so I wouldn't worry about the lean spots just yet. If the AFR *jumps* between very rich and very lean over and over again and/or stays pegged high or low, that means the LC-1 needs to be recalibrated. When you recalibrated it, something could have gone wrong. FWIW, I removed the Cal wire in my car and just use Copilot's calibrate function or do the First Time Calibration procedure, which involves removing the sensor and unplugging the connector... the Innovate PDF explains it in detail.

aaronjb · August 10, 2008, 16:36

Quote from: "Beanie"You ID'ed the problem, but didn't actually fix it. After fixing (replacing PCV valve), it will probably be back to normal, so I wouldn't worry about the lean spots just yet.

Hmm - I'm not so sure Kevin - remember the vac line that would normally go to the PCV valve is disconnected from it and blocked off at the intake manifold end.. so nothing can go anywhere there. I can't see how blocking off a vac source could make it go lean - rich, yes, but not lean s:? :? s:?

This gets more confusing, though. Sigh - I'm about done with this, really. Next step is a gallon of petrol and a match.

Step 1:

Stock ECU. Stock intake. Stock airbox. Stock injectors. Still the TS manifold though and only ONE O2 sensor.
Result: Runs OK. ECU has trouble learning it's fuel trims for obvious reasons, but the AFRs are about right and it drives nicely for a few hundred yards.

Step 2:

Stock ECU. Top Secret intake pipework. Stock injectors. Still the TS manifold and only ONE O2 sensor.
Result: Surprisingly, runs OK. Little leaner than last time (MAF tube has no vanes), but the AFRs settle to roughly OKish - like I say, little lean, but drives OK

Step 3:

PFC. Top Secret intake pipework. Stock injectors. TS manifold & one O2 sensor.
Result: Runs.. like a bag of crap. But I think that's the tune - it's way off with the stock injectors and needs fully retuning.

So, basically. I've learnt nothing, really. The only way I can see to get any conclusive results is going to be to put the car FULLY back to stock - stock airbox, stock injectors, stock MAF, stock manifold, stock exhaust. And then see if it's OK. Only then would I have any kind of meaningful baseline s:(

s:( because at the moment I can't tell what is a bad tune (highly likely in step 2 & 3) and what is a real fault.

So tomorrow I think I'll put the 525cc injectors back in and just drive around auto tuning. One of two things will happen:

1. I'll have a melted block, holed pistons and a smashed rod. At which point I'll sell the bits and be done with it.
2. I'll be able to tune around the problem and go back to work on Wednesday.

I'm not sure I care which happens, anymore. s:evil: :evil: s:evil:

aaronjb · August 10, 2008, 19:10

Oh for fucks sake.

I put the bigger injectors back in..

And now it's only running on three cylinders!

What do I need to do to catch a break around here?

Time to go car shopping.

markiii · August 10, 2008, 19:14

thats a good thing I read your last post and had pretty much decided that ahisnt all odds you had a dodgy injector

bet if you put stock ones back again it fixes that

assuming so, stick te stock ones back remap temporarily and send the big boys off for testing again

kanujunkie · August 10, 2008, 19:43

can we have a car torching party then Aaron, what with your issues and my gearbox s:evil: :evil: s:evil:

Anonymous · August 10, 2008, 19:43

No good then Stu?

kanujunkie · August 10, 2008, 19:45

nope, gotta all come out again and be reconditioned yet again s:evil: :evil: s:evil:

Anonymous · August 10, 2008, 19:45

Definitely the box then, nothing to do with the clutch?

kanujunkie · August 10, 2008, 19:51

dont think so, clutch is fine, works a treat, just the gearbox that whines exactly the same as it did before it was reconditioned s:roll: :roll: s:roll:

Anonymous · August 10, 2008, 19:53

Fucksocks s:(

s:(

kanujunkie · August 10, 2008, 19:56

exactly, anyway back on Aarons woes s:wink: :wink: s:wink:

aaronjb · August 10, 2008, 20:18

Quote from: "markiii"thats a good thing I read your last post and had pretty much decided that ahisnt all odds you had a dodgy injector

bet if you put stock ones back again it fixes that

assuming so, stick te stock ones back remap temporarily and send the big boys off for testing again

It could be water in the plug wells, too - it did absolutely piss it down while I was working on the car. Four times.

I'll see tomorrow, when hopefully it won't rain quite so damn much.

Now I'm off to change into some dry clothes s:? :? s:?

DAZ400 · August 10, 2008, 21:25

My Apexi turbo runs on stock injectors with extra mapping from the greddy and they are sufficent with the higher pressure feul pump.

I would suspect the injectors, they can be very funny, intermitent, sticky etc. Like i said Perry's engine blew and it was down to a faulty injector.

can you try manualy mapping the injector duty cycle with the stock injectors, does not matter if it is too rich too start with, better than too lean.

Cheers

Darren.

Anonymous · August 10, 2008, 21:32

Maybe, just maybe, the stock ECU can compensate for one bad injector. A PFC certainly won't. That would explain why it runs OK with the stock ECU and crappy with the PFC. Hang in there, Aaron.

If you want to do the auto tuning after ensuring all the parts (injectors etc.) are working, try the Online Auto Tuning. You'll get really fast results. Luckily I just fixed a bug in that... it was complaining about bad data received after each base map write. I've used it myself since then and it works just great for me. Version 3.1.

aaronjb · August 11, 2008, 16:31

Well.. I discovered the cause of it running on three cylinders - and as I suspected.. completely unrelated fault, from what I can tell.

It was either:

The 2" of rainwater in the no 2. plug well (although it seemed fairly OK with that!)
The fact that the -ve lead was hanging out of the injector connector for No 1 injector.

Shitty fucking cheap badly put together injector connectors.

I'm getting very tempted to have it trailered to somewhere like Thor and just saying "Make it work, here's my credit card." - it's just one fault after another, and in the course of trying to find the fucking problem all I'm doing is creating more!

markiii · August 11, 2008, 16:50

aah the Dan approach :-) :-) :-)