Brun

I had this done today. I was just wanting your thoughts to this in relation to this thread.

Pay particular attention to the O2 sensor peak.

I thank you

*Sonic*

taking a look now mate

*Sonic*

You got any more log files

It looks like this was all in one gear ?, voltage on Lambda is a little lower than I would expect (mine reads about .950 on WOT)

a fair amount of knock correction too (again I get some but not a great deal)

BTW I am absolutly NO expert in Delta Dash readings, as I am still learning what all the readings do, and how they correspond to each others readings

WREXY

Brun,

I presume that run was done with full throttle. If so you are running very very lean. Your car is also probably detting. There is lots of knock correction and there is 4 degrees knock correction in the 5000 rev danger zone.

You must look into why the car is running lean. It could very well be a faulty MAF sensor.

What sort of mods have you done?

In the mean time, do not give your car any stick whatsoever. Keep on light throttle and keep below 3000 revs till it's sorted. If you give the car stick your engine will let go.

Let us know the outcome.

Cheers,

George.

[Edited by WREXY - 9/13/2003 11:44:41 PM]

Brun

My mota is running a full decat, k&n 57i and vta dumpvalve

WREXY

Those mods are OK. I'd say MAF sensor is the culprit.

Cheers,

George.

Brun

The run was done in 3rd gear right to the red line. I don't understand the graphs one bit
The reason i did this was to try and get an answer to the AFR gauge issue, but it looks like i will have to visit the gararge. Will a slightly failing sensor show up on the select monitor?

SiHethers

I'm pretty sure you've got a failing MAF too. Because not only are you running very lean, but also with way too much advance. A replacement MAF is only ~£70 so not too expensive. If it was a fuelling issue, say from a failing pump, the ignition timing would still be appropriate.

Completely agree with WREXY, DO NOT rev above 3000rpm and stay off boost until you've fitted a new MAF and re-tested.

Simon

Edited to say this will not show up as a error code on the select monitor, so you just have to tell them you want it changing, even if they say there's no error showing.

[Edited by SiHethers - 9/14/2003 12:07:03 PM]

WREXY

The way you did your run is the correct way to test the MAF and to test everything really.

The MAF won't come up as a fault on the select monitor when it's running lean. It usually only shows up when it's running rich in closed loop mode. Did you look at the Delta Dash diagnostic trouble code reader to see if the MAF sensor came up as being faulty? I think you'll find it didn't. It won't come up on the select monitor either. I'm afraid you will have to do a try and test.

I however, think it is your MAF sensor. Your O2 sensor readings are very very low. The best thing to do is, if you can find a friend that has a scoob, same model as yours, try his MAF sensor by using Delta Dash the same way in which you did your run and see if you go back over 0.89volts. If you do, go over, you know your MAF is faulty. Or perhaps the garage will let you try out a new MAF before buying.

You need to fix it ASAP cos you're running very very lean which will result in a blown motor. Don't give the car any stick whatsoever. Let us know the outcome.

Cheers,

George.

edited to change, open loop, to closed loop.

[Edited by WREXY - 9/14/2003 10:03:31 PM]

WREXY

Cross posted with Simon.

Brun

I've just done an ECU reset to see if it was making allowances for anything that was failing, but there is no difference
I'll see if anybody has anything else to add tonight and i think a new MAF will be put on order tomorrow

WREXY

Just to give you an idea Brun. Anything on a scoob and I'm talking MY99/00 here, with under 0.89 volts O2 sensor readings, (unless it's been remapped that way e.g Ecutek), means that something is not right. It usually means the MAF sensor is faulty and is under reading the air it's actually getting. It passes this info on to the ECU and the ECU then gives less fuel which will result in detonation and then bye bye engine.

Sometimes the MAF sensor can be OK but it can still under read due to some induction kits that sit in the wing. The APS induction kit causes the MAF to under read so the MAF calibration map neds sorting to get the mixtures right. In your case with the K&N 57 kit, it is OK. It is MAF friendly.

Your ignition timing column shows you are running too much advance as Simon pointed out. The fuel injector duty cycle seems a little low as well. This indicates that the ECU is providing less fuel.

It seems to be pointing to a faulty MAF sensor.

Cheers,

George.



[Edited by WREXY - 9/14/2003 10:07:26 PM]

Brun

I thank you very much
I'm glad there are people like yourself out there who are able to describe things in such a way that a muppet like myself is able to understand

[Edited by Brun - 9/15/2003 1:48:03 AM]

Bob Rawle

Brun YHM ... of far more significant is the prolonged knock retard that is present ... that does indicate lean running, at only 13 psi the engine load is not great but maf sensor should be replaced as a precaution.

bob

*Sonic*

would those readings not also indicate a potential lambda sensor on its way out too?

Brun

Ok - new maf is installed to the tune of £73
I've had a quick blast and nothing seems to have changed, but then again, i hadn't noticed any thing wrong in the first place
I spent the whole trip with my eyes on the AFR and at anything past 2k revs on WOT it dives straight into the green
I'm gonna see if i can get another Delta dash done very soon and hopefully i can put all this behind me

[Edited by Brun - 9/15/2003 1:15:19 PM]

WREXY

Green above 2000rpm to the rev limit sounds right. Let us know how you go when you Delta Dash it.

Cheers,

George.

Brun

No problem
Delta Dash is arranged for Saturday
I've also noticed that the gauge is one light deeper into the green on WOT - so i thinks thats gotta be a good sign.
[safe mode on]I'm still not thrashing it though cos i'm not counting my chickens. [/safe mode off]


[Edited by Brun - 9/15/2003 11:40:40 PM]

Brun

Delta dash complete I'll post it up later.

There is no knock correction now but the O2 sensor peak is still only .86v
I was quite happy until the trip home. The AFR has returned to its static old self and is not jumping into the green under wot
It looks like i've dropped another maf sensor......... in 5 days flat
I've had a look aroud the maf sensor area and have found a 2" crack in one of the K&n parts. It's only a hairline crack, but i assume that none filtered air is finding it's way in. I'm guessing this could lead to maf failure?? but in 5 days flat????????? wtf


[Edited by Brun - 9/20/2003 3:40:51 PM]

HHxx

Don't think the maf has had it just yet.

If air is leaking in after the sensor, that would explain a leaner running. i.e air is getting into the engine that was not accounted for.

H

Brun

It's leaking just before the sensor
You can just about make it out in this pic. This is the part that the cone attaches to



[Edited by Brun - 9/20/2003 4:05:15 PM]

Brun

New Log

[Edited by Brun - 9/21/2003 12:28:48 PM]

*Sonic*

Brun

the link doesnt work

WREXY

Brun,

That split is on the MAF's housing and is dangerous. You need to replace the whole MAF housing which will come with a new MAF sensor. Unfortunately it is quite expensive. As before, do not give the car any stick whatsoever. Keep us posted.

Cheers,

george.

*Sonic*

Wrexy that split isnt on the MAF housing, it is on the bit that comes with the K & N filter, it bolts onto the MAF housing

WREXY

Oh, I see. I read Brun's post too quick. Yes it's to the left of the housing, so it should be cheaper to buy then. The unfilterd air getting through that split has probably contaminated the MAF sensor or is disturbing the air flow causing the MAF to under read.

Process of elimination now. Replace that piece, the MAF sensor and do another log with Delta Dash. Take it easy with the car till then.

Cheers,

George.

Brun

The clicky is now fixed

WREXY

Yep. Lean again. Fix that induction kit, then test with your current MAF sensor. If the mixtures are OK, you get away with having to buy another MAF. If not, new MAF again.

Cheers,

George.

Brun

I don't really understand the log info. What off the log makes you say it's running lean? and what should i be seeing if the car was as it should be?
I've had another delta dash done today and the O2 sensor was reading lower than Saturdays effort Is it time to replace the Llambda?

Edited to add that the cracked bit was sorted before todays delta Dash

[Edited by Brun - 9/21/2003 4:03:54 PM]

*Sonic*

I would replace the Lambda anyway as a matter of course, I did on mine, and it made the world of difference

John Banks told me they are a consumable item, that have a life of around 3 years