Bad idle question and scan attached.

[munster]

Good luck and watch those knuckles!

Man my left inner wrist area is a red as a baboons @rse

[kentphil1]

Man my left inner wrist area is a red as a baboons @rse

 

Too much info there, that image will take a while to shift

[YellowCar]

We feel your pain, we've all been there

[munster]

Well, I finally managed to seat the hose & O ring, it was quite difficult in such a tight space but loosening the jubilee clips did help enormously BUT what a b@stard of a job!!

My left forearm is covered in red marks and bruises and I have to admit to swearing at the engine quite a lot!!!

But, on starting the engine and letting it warm up, it seems to have reduced the searching for revs to a minimal amount, if not completely - between 2 of the smaller lines now as opposed to what was happening previously.  

I will drive it for a few days then scan it again and see whether the Lambda fault comes back - I expect it will as if it is cream crackered it's cream crackered!

Thanks for the advice guys, really appreciate it :clap:  - but don't go away I'll probably need loads more over the next weeks, months, years

[YellowCar]

No problem mate glad you're getting there. For what it's worth the idle on my vrs was never rock steady, would very gently blip. But yes, now you've done this work clear the memory and see what pops up now. Let us know how you get on.

[kentphil1]

What is also worth doing as the gasket is about £3 is to remove the throttle body and give it a good clean, and also take the air temperature sensor out and give it the once over with some isopropyl alcohol.

 

Do you know anybody local who has VCDS who can monitor your Lambda values and voltage to see what is going on?.

[YellowCar]

What is also worth doing as the gasket is about £3 is to remove the throttle body and give it a good clean, and also take the air temperature sensor out and give it the once over with some isopropyl alcohol.

 

Do you know anybody local who has VCDS who can monitor your Lambda values and voltage to see what is going on?.

True that cleaning the throttle body is well worth doing. I used carb cleaner and contact cleaner on intake air temp sensor, worked a treat, whatever you use clean the element on it gently, soaking it is best.

[munster]

Am off on a 4 day bike trip tomorrow morning but will clean the TB when I get back.

My friend has VCDS but is a novice with it how does he monitor the Lambda values?

[kentphil1]

Does he have VCDS Lite or the full version?.

[munster]

I'm pretty sure he has the full version.

[munster]

Hi Phil

I'm back from Belgium so I replaced the dipstick guide I snapped   when doing the hoses and started her up and all appears to be good.

I asked my friend what version he has and it is full version so what do I need to do to see how well the Lambda is operating, or not!

[kentphil1]

If he looks at the online manual here - http://www.ross-tech.com/vcds/tour/main_screen.php, Section 13 (not page 13), you can select what you need to monitor and read data real time. It is best if he has a genuine cable and full version, if he updates free to latest software version - currently 15.7.1 - as it has latest codes and is more user friendly. If it is a clone cable, then don't upgrade, and to be honest life wont be so simple as you don't know what has been altered in the software to effect the clone. In extreme circumstances you might brick the ECU. If it was my car, I would check and if not genuine cable, I would politely decline the offer, but that is just me, Where are you located?, North, South, East or West of the country?.

 

if you just want to read Lambda voltages, you can do it with a voltmeter across the sensor terminal pins under the floor on the drivers (o/s) of the car.

 

Sorry for not replying, was going to reply 2 days ago, then issue with my daughter sprung up and I forgot.

 

Hope it helps,

 

Phil

[munster]

 

Sorry for not replying, was going to reply 2 days ago, then issue with my daughter sprung up and I forgot.

 

 

No worries mate, family takes precedence over someone elses car - everytime.

[karlbar2k]

Ok just read the thread and I see you have found some of the culprits - hunting at idle is 99.999% down to vac leaks.  vac leaks also normally equals Boost leaks as well so its always good to get rid of them.  

 

on mine I started with the big Y pipe and ended up replacing nearly all the pipes that touch the manifold.  the "suction spray jet pump" being a particularly fun one as well.

 

like you I have replaced the elbow in the sump which is one of the worst jobs ever, I ended up with a length of hosepipe gaffer taped to the end of a hoover to get the bits out of the hole

 

if you have full vcds you can monitor block 032 for fuel trims which is the easiest way to diagnose VAC and BOOST variances.  I cant remember the specifics but if you search block 32 you will find it.

 

on a previous thread of mine I have also added in extra "one way check valves" to some of the smaller lines as there are a couple in the system that can fail or leak.  I used some metal ones from ebay.. if I can find the links I will add them later

[karlbar2k]

http://www.briskoda.net/forums/topic/267276-low-boost-which-blocks-to-log/

[munster]

Thanks for the link Karlbar2k. I am working all weekend so I will have a bash at that in the week.

[karlbar2k]

I still have photos but I think over the year with the various server move briskoda has gone through some of my posts have gotten lost.

[munster]

Ok so its been a few days since I cleared the faults so I got it scanned again and have 2 faults, 1 is the flap motor which I knew about anyway! The other is 16804 cat efficiency below threshold I looked on VCDS wiki page and it says it could be a leak in the exhaust system. The PO changed the downpipe so I'm wondering whether it isn't sealing properly at the join, or is it something else, thoughts?

[karlbar2k]

A leaking exhaust can cause some problems but get that block 32 scanned and it will confirm vac or boost leaks

[kentphil1]

I take it the car still has a cat in the system with the new downpipe?.

[munster]

Do you know what Phil, I have no idea

I shall have a look tomorrow morning, I just assumed it did!!!

[munster]

I am assuming that this beasty is the Cat? Get it beasty/cat...........I'll get my coat

[YellowCar]

Where was the downpipe from? It would look like that, but then so would a dummy cat, part of the mot rule says something about it having to look like a cat, as well as actually be a cat. Question is, is it a cat if it looks like a cat or is it a question of what our perception of a cat is, it could be a cat because it's not me, but then it's not sat on a mat...This raises all manner of philosophical points of inquiry...

Upshot of is, it might be, but might not be

[munster]

Where was the downpipe from? It would look like that, but then so would a dummy cat, part of the mot rule says something about it having to look like a cat, as well as actually be a cat. Question is, is it a cat if it looks like a cat or is it a question of what our perception of a cat is, it could be a cat because it's not me, but then it's not sat on a mat...This raises all manner of philosophical points of inquiry...

Upshot of is, it might be, but might not be

How would I tell? is there anything in particular I could look for? I kind of took it for granted that if it was de-catted it would have just been a straight through pipe and if it had the lumpy shape it was a cat. Interesting and peculiar.

So if it isn't a cat - what does that actually mean? - in laymans terms please - as in mot failure etc???

[kentphil1]

Technically a decat is a possible mot fail if the emissions cannot be brought under control, and I also think the mot rules were changed a while back to say if a cat was fitted at manufacture it must be present on the car, but I am not certain on that point, so any testers, please jump in on that one with factual info if you would not mind.

 

If it is a decat, it may have a ghost or empty cat chamber to make it look like one. far more likely is that it is a cheaper end sports cat and it is struggling to keep up with the job at hand.

 

The only certain way is to remove it and look inside the pipe to see if it has any "guts" inside it really.

 

When you got it scanned, did he check that both Lambda sensors were functioning and giving a reading?, If one is unwell or down that could also give you the code - more info here - http://wiki.ross-tech.com/wiki/index.php/16804/P0420/001056