Try looking at your lon term fuel trims after it has had time to adapt. are they reducing as you go up in maf size?
Was one flow straightener out/in?
Is yours a ko4 or hybrid?
Was one flow straightener out/in?
Is yours a ko4 or hybrid?
Morning John
the fuel trims are starting to come back to zero now. initially with the thickest sleeve the long term trim was at -7%, yesterday after taking out 0.5mm it was at -5%. its heading in the right direction. The first (filter side) straightener has been in for the last two tests, it will stay in now for the foreseeable.
its a standard K04
Morning
If your fuel trims are coming into line, then the maf readings are getting nearer to the ones the map was written for. This does not say that the maf is reading accuratey in vag com, just that the values correspond to the correct possitions in the map.
Fuel density does vary a tiny bit, and fpr springs are not absolutely accurate, but i'd expect fuel trims to be + or - 1%or less. This of course only works with no boost or vac leaks.
You need to make sure you're doing multiple logs as well. They need to be repeatable after a few runs to realy get any accuracy. I once got my ihi to read 275g/s on a single log, (effin cold out and cold engine), where it was only repeatable in the 245-250g/s range. You need to ignore single logs.
Personally, I'd chuck the aluminium maf as I don't see what it gains you, stick a standard one on, and then check your fuel trims. It's a lot quicker than all this messing about.
If your fuel trims are coming into line, then the maf readings are getting nearer to the ones the map was written for. This does not say that the maf is reading accuratey in vag com, just that the values correspond to the correct possitions in the map.
Fuel density does vary a tiny bit, and fpr springs are not absolutely accurate, but i'd expect fuel trims to be + or - 1%or less. This of course only works with no boost or vac leaks.
You need to make sure you're doing multiple logs as well. They need to be repeatable after a few runs to realy get any accuracy. I once got my ihi to read 275g/s on a single log, (effin cold out and cold engine), where it was only repeatable in the 245-250g/s range. You need to ignore single logs.
Personally, I'd chuck the aluminium maf as I don't see what it gains you, stick a standard one on, and then check your fuel trims. It's a lot quicker than all this messing about.
ok i see what your saying... its weird that i looked at the long term and didnt put the two together until you asked the question....
it will be interesting to see what happens tonight.... i had to make a decision earlier, he's getting very busy now and it doesnt look like he will get another boring session in this month. im hoping by going out to 71.5mm it will be near enough to leave for a while. im happy if it is on the rich side.
i did multiple logs last night and it repeated even after a second TBA and fault code reset
the problem with ditching the Aluminium MAF housing is getting another. at the minute it is quicker to get this one flowing right (it has also been made a press fit into the Dynatwist and we all now what happens when aluminium has been together for a while). if i could get it apart, do we know anywhere that sells a cheap second hand MAF?
Brand new ones are 70£ exchange from the dealers. Most vag specialists have a few kicking around.
What happened to your original?
What happened to your original?
its the exchange part that is the problem.. A friend was selling his LCR and he had this aluminium MAF housing. i kept my sensor but swapped housings as he didnt have his old one (i dont know why)
i'll see what i can do on the housing front. i must say though it has been fascinating seeing how much of a difference a few mm can make on a sensor housing..... Strange that this this problem hasnt come up before.
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on a seperate note to this, i want to get rid of the boost spike i have. i dont see it it as much on Vagcom (baud rate?) but on the gauge i can sometimes see 1.8bar.
im thinking about going along the same route as Dave to smooth it out with an MBC, what do you think John? i also had a quick look at an electronic boost controller.
im thinking about going along the same route as Dave to smooth it out with an MBC, what do you think John? i also had a quick look at an electronic boost controller.
You won't see the boost spike, as the map sensor doesn't read over 2540, but there's nout wrong with 1.8 bar, mine runs 2 bar sustained, 1.8 bar by 7000rpm. MBC will limit this, and take the spike away, but the car won't be as quick, but may be smoother.
They charge you 20£ extra wth no exchange, but usually any old maf will do, as they are unlikely to check the part numbers match.
They charge you 20£ extra wth no exchange, but usually any old maf will do, as they are unlikely to check the part numbers match.
thanks John, im not too worried about loosing the spike and the car being slower (on the rollers), the spike is pretty much unusable power on the road as it is just wheel spin anyway. my understanding was it wont spike as much but will hold boost further up the rev range, is that correct? if so cant i just dial in 1.6bar to get a little extra?
i did get a quote from Seat for a new MAF without the exchange, his price was £200
i did get a quote from Seat for a new MAF without the exchange, his price was £200
Ching.
Im hunting for some mental tubing now. Might be able to get some... So dont stress about!
don't tell them you're not going to exchange, just say you need to take it off the car before you can exchange it. My local dealers charge 20£ untill you return the exchange item (never)
the boost controler if connected right should limit the maximum boost, but let the n75 control the boost up to that level, ie just bleed off over boost.
the boost controler if connected right should limit the maximum boost, but let the n75 control the boost up to that level, ie just bleed off over boost.
Hehe sneaky
id have to do that at another dealer, i buy too much from MK SEAT (we're on first name terms, which isnt a good sign)is Dave running a bleed valve? i didnt think he was. you can ditch the N75 all together (leave it plugged in though) cant you? i need to do more research, ive never looked into MBC's before.
Sorry I'm late. I did run an mbc as a bleed before I ditched the N75 altogether. (just plugged in electrically).
I think there's less tolerance on Revo Stage 2 than Revo Stage3 to do the same, but I'd consider it worth the try.
Euro Car Parts wouldn't be bothered about not getting the exchange one back. Good Bosch recons. (As are all dealer supplied units).
I think there's less tolerance on Revo Stage 2 than Revo Stage3 to do the same, but I'd consider it worth the try.
Euro Car Parts wouldn't be bothered about not getting the exchange one back. Good Bosch recons. (As are all dealer supplied units).
I never thought of going to euro's, Seat always seem so cheap that there isn't a need to go elsewhere, I'll give them a bell.
What are you running now with regards to the mbc? I take you're talking about the deviation error when you say there's less tolerance? How far have you managed to push yours Dave?
What are you running now with regards to the mbc? I take you're talking about the deviation error when you say there's less tolerance? How far have you managed to push yours Dave?
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