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Ronin225's Candy rimmed Black LCR - Project 500-4WD, Cage installed and bigger turbo
- Thread starter Ronin225
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Wonder if your other mods have got the car to the point where the emissions through the 100 cell cat are making the ECU think the cat is failing, similar to what happens with a decat. May just need one of those lambda sensor spacers if that's the case.
That's a different thing though - MOT is testing for quantities of certain things in the fumes (carbon monoxide etc.), the lambdas are just testing for air/fuel ratio.
Just had a look at that code on the Ross-Tech wiki - http://wiki.ross-tech.com/wiki/index.php/16804/P0420/001056
If you check the thread on VWVortex that the above has a link to that's the same code that a lot of folk get when putting in a decat. I'd say your car may have been running a bit rich if the original MAF was on the way out as someone else on the last page suggested.
Just had a look at that code on the Ross-Tech wiki - http://wiki.ross-tech.com/wiki/index.php/16804/P0420/001056
If you check the thread on VWVortex that the above has a link to that's the same code that a lot of folk get when putting in a decat. I'd say your car may have been running a bit rich if the original MAF was on the way out as someone else on the last page suggested.
I have looked around at the code before it occasionally flagged but never had the EML with it
The MAF has made a big difference so if you havent i'd try that
Feel free to have a nose around at the trackday as it wont have much in it, still having thoughts of caging it
Most fault codes have to flag a certain number of times (often within a certain period of time too) before they'll trigger the EML. More serious codes will trigger the EML after fewer occurrences or straight away.
If this one had been what it said it was (i.e. that the cat was below optimal) then that wouldn't mean anything dangerous on its' own, just that you'd need a new cat to sort your emissions out. I reckon you were getting it because the mixture was just far enough out to affect AFRs and make a difference to performance. Glad its' sorted now anyway.
I keep looking at your wheels and wonder what red wheels would look like on my red car
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I keep looking at your wheels and wonder what red wheels would look like on my red car
Awesome if colour coded. Do it
Pain the ass time, its back with the same fault code and eml
Car does pull better than before with new MAF but obviously this is now lambda related
I've put out the help request to Phill to log block 031
If it is the lambda, i still have the pre cat one from the s3 (there was no post cat one) assuming it will be pre cat as been told this one controls fuelling
Car does pull better than before with new MAF but obviously this is now lambda related
I've put out the help request to Phill to log block 031
If it is the lambda, i still have the pre cat one from the s3 (there was no post cat one) assuming it will be pre cat as been told this one controls fuelling
"Cat below efficiency threshold" points to post-cat not pre
Post cat sensor is just a tell-tale to tell the ECU if the cat is working properly, hence why the EML comes on with a decat. It could be your 100 cell cat is giving up the ghost, but I'd check for exhaust leaks from the downpipe at all its connections first.
Spot on with the pre-cat controlling fuelling, its the sensor with more wires going to it.
Post cat sensor is just a tell-tale to tell the ECU if the cat is working properly, hence why the EML comes on with a decat. It could be your 100 cell cat is giving up the ghost, but I'd check for exhaust leaks from the downpipe at all its connections first.
Spot on with the pre-cat controlling fuelling, its the sensor with more wires going to it.
Car was up on the ramps a few weeks ago when the cam belt was done and i did check the exhaust but no signs of leaks, only connection i didnt check was downpipe to turbo as i couldnt see it
8bit pointed out the bigger alterations trying to pull fuelling back and wondered if the precat was misreading whats going into the cat whats coming out would be out of spec hence the EML
Until block 031 is logged its all guess work, hopefully should be meeting up with Phill next week and get some answers
8bit pointed out the bigger alterations trying to pull fuelling back and wondered if the precat was misreading whats going into the cat whats coming out would be out of spec hence the EML
Until block 031 is logged its all guess work, hopefully should be meeting up with Phill next week and get some answers
Pre-cat lambda checks and influences the mixture, post-cat as Craig says is mostly just to monitor the cat. That error is caused by the post-cat lambda readings being outwith spec. Logging block 031 will give some clues, that one shows you actual vs. specified lambda.
If you can, log block 001 again now you've got a better MAF on there, see if it's still pulling out fuel. If mixture control all looks right then I'd say it's an issue with the cat or more likely one of the lambda sensors. If the post-cat lambda is dying then it usually gives different codes (mine threw various codes but not that one when it was stuffed).
Ideally when you get a chance, log block 001 and 031, then 001 and 002.
If you can, log block 001 again now you've got a better MAF on there, see if it's still pulling out fuel. If mixture control all looks right then I'd say it's an issue with the cat or more likely one of the lambda sensors. If the post-cat lambda is dying then it usually gives different codes (mine threw various codes but not that one when it was stuffed).
Ideally when you get a chance, log block 001 and 031, then 001 and 002.
So there are Just had a look, looks like your engine was colder doing the runs on the new MAF, that will make a difference - the ECU runs the mixture differently until the engine is up to temp. Looking at your first run on the old MAF the adjustments are greater on that log than on the other two as the coolant temp is lower.
On the positive side, it looks like your thermostat is working fine If you can get hold of Phill to help with some logging then get the ones I suggested but give the car a good 20 - 30 mins driving to warm it up properly. He'll be able to see the real coolant temp on the screen while setting up for the logging so if it's not within a few degrees of 90 then it needs to warm up a little more.
Just had a look, looks like your engine was colder doing the runs on the new MAF, that will make a difference - the ECU runs the mixture differently until the engine is up to temp. Looking at your first run on the old MAF the adjustments are greater on that log than on the other two as the coolant temp is lower.On the positive side, it looks like your thermostat is working fine
If you can get hold of Phill to help with some logging then get the ones I suggested but give the car a good 20 - 30 mins driving to warm it up properly. He'll be able to see the real coolant temp on the screen while setting up for the logging so if it's not within a few degrees of 90 then it needs to warm up a little more.Today been getting ready for the track, doing bits and pieces
All fluids topped up, service the 007, made a little goodie bag emergency repair kit, fitted new wipers, washed it and emptied the catch can
So all ready to give it an absolute thrashing tomorrow and i will be pushing it quite hard too
Will post pics/videos up when we get back
All fluids topped up, service the 007, made a little goodie bag emergency repair kit, fitted new wipers, washed it and emptied the catch can
So all ready to give it an absolute thrashing tomorrow and i will be pushing it quite hard too
Will post pics/videos up when we get back
Nice to meet you today and thanks for the passenger ride! I'm very impressed with how well your car handled and loved you brakes. I think I'm going to sort the handling out now you've inspired me. I defiantly want to do a track day as well.
Gutted i couldn't make it (I'm ill for those that don't know) looking forward to the pic's and vid that i know Barn will have taken.
It's a shame you did come Phill it'd of been good to have meet you. Hope you feel well soon. I think between Barn and his Dad there should be of few photos! I forgot to take any my self. I don't often get to talk cars so enjoyed talking to Tim, Barny and RDS. going out as a passenger has convinced me I need to have a go.
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