I thought the two lambda values were pre and post cat, rather than actual vs. requested?
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First rolling road figures, low output? Fuelling probs?
- Thread starter 8bit
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I thought the two lambda values were pre and post cat, rather than actual vs. requested?
Had a quick look the other day, can't see or feel any leaks. That said, I'd have thought that a leak after the turbo would have cause it to run rich, cos that way some of the air the ECU is thinking is getting to the cylinders actually isn't?
No idea when the plugs were last changed, don't remember seeing anything in the service log book but will have a look later. I'll get them changed soon, got the car booked into a local VAG group specialist to get fuel filter changed, pump and fpr checked out, vacuum and boost hoses checked out and change the brake fluid and gearbox oil while they're at it. Car isn't going in until 2nd October tho so if I can find out what's causing the lean running beforehand then it might save on some labour costs.
That is odd then. From what I've read on here, if it is that the requested fuel is low then that would suggest MAF (which we've already eliminated) or a dodgy map. This car hasn't been remapped though!
Still worth changing the fuel filter and plugs? It's almost due the 50,000 mile service anyway, the timing belt and water pump were changed in February and oil and filter not long ago so happy enough to try that.
Still worth changing the fuel filter and plugs? It's almost due the 50,000 mile service anyway, the timing belt and water pump were changed in February and oil and filter not long ago so happy enough to try that.
When I said MAP I meant the Mass air pressure sensor near the throttle body mate, these engines have both MAP and MAF to make things complicated lol, could be duff?
I'd try some injector cleaner, fuel filter and plugs first. Also check for splits in the inlet pipe that connects to the turbo inlet from the air filter.
I'd try some injector cleaner, fuel filter and plugs first. Also check for splits in the inlet pipe that connects to the turbo inlet from the air filter.
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Haha, sorry yeah I did realise you meant the MAP sensor, when I said map I meant as in the fuelling map on the ecu, I read a thread on here where someone was getting lean figures like me, his problem turned out to be a dodgy remap.
I'd have thought that it's unlikely to be an intake leak now, doesn't the ECU compare the MAF readings with those from the MAP and throw an error if the two are different? I will check the TIP over today tho.
Did think about that actually, to be honest I can't see how it could be something wrong with the current map (believed to be OEM) unless the car had been remapped by some previous owner then put back to some incorrect version of the standard, factory map. Because I'm not convinced this is what's wrong, I wouldn't want to get it remapped, even for a five hour trial, while the car is running lean, particularly as I don't know how long it's been running lean for and how hard the previous owner drove it.
Also, as everything else on the car appeared to be standard when I got it I don't think it was ever remapped.
Also, as everything else on the car appeared to be standard when I got it I don't think it was ever remapped.
Had another look over the car today. When inspecting the fuel rail I found that the tops of the inlet manifold under the injectors seemed to be soaked in liquid, see below:
Didn't notice any smell of petrol but didn't want to stick my hand in there to get some on my fingers to check as the engine bay was hot, so will do later once it's cooled a bit. Either way tho, I guess there shouldn't be fluid of any sort really on there?
Didn't notice any smell of petrol but didn't want to stick my hand in there to get some on my fingers to check as the engine bay was hot, so will do later once it's cooled a bit. Either way tho, I guess there shouldn't be fluid of any sort really on there?
Yeah that's quite alot of liquid mate, my inlet has a small amount of oily residue on the bottom of one but looks like your injector seals might be duff. Check if it smells for petrol
Just been out, still can't smell petrol in there. Managed to get some of the fluid on a bit of kitchen paper, didn't smell of anything much.
Lee, if it is a breather hose then I can't see where it would be to be leaking onto the top of the inlet? Also if that's what's causing the fluid in there then could that be what's causing the lean running?
EDIT: Or is that the breather hose, the black one that runs along the fuel rail?
Lee, if it is a breather hose then I can't see where it would be to be leaking onto the top of the inlet? Also if that's what's causing the fluid in there then could that be what's causing the lean running?
EDIT: Or is that the breather hose, the black one that runs along the fuel rail?
It will be forced out maybe up to the sound deadening then onto the cam cover?
The breathers are under the inlet and, well, to the right of the cover.
It effects boost, so chances are it would run lean.
The breathers are under the inlet and, well, to the right of the cover.
It effects boost, so chances are it would run lean.
There's no sound deadening in there, if you mean the mat that comes clipped to the underside of the bonnet? Although having said that, before I took the engine cover off to check it again just now I noticed that the staining seems to be just below the engine cover, you can just see it underneath the little curved bits at the front of the engine cover so it clears the inlet. I'll have a look at the bottom of the inlet cover again later.
If that is what's causing that, would the hose in question be one of these?
http://www.forgemotorsport.co.uk/content.asp?inc=product&cat=190202SILH&product=FMTTBH
If so, anyone know where I can get the same thing in red?
Yeah that under the bonnet.
Could be any of those pipes, no other choice but to get dirty lol
Install a catch tank, no need for any of them then
Could be any of those pipes, no other choice but to get dirty lol
Install a catch tank, no need for any of them then
Did think about a catch can but right now the cheapest fix is going to have to be the choice. Do you or anyone know the internal diameter of those breather hoses? Could be an option to just get a length of the correct diameter of oil-resistant silicone hose and cut some bits to length for that?
they are leaky injector seats....
this will cause a leak and will affect your fuel trims
could be the top injector seals also id change both to be sure
this will cause a leak and will affect your fuel trims
could be the top injector seals also id change both to be sure
OK, i'll stick that on the to-do list for the garage, was going to ask them to check the injectors, fpr, fuel pump and change the fuel filter anyway. Would I see that on the VAGCOM logs at all? Which block shows fuel trims?
can check fuelling yes block 031.
you want to see 0.8xx under load. youve logged these already havent you
you want to see 0.8xx under load. youve logged these already havent you
Yep, never went below about 0.93 I think, logs are earlier in this thread. I know that's the lambda figures in 031, is that what you mean by fuel trims? According to my block description sheet, block 116 lists "Fuel Correction Factor" - might that provide any clues?
youve already shown that fuelling isnt crrect, its the requested aswell...
tbh mate, id change the filter, plugs and sort them leaking manny seats then relog to see.
tbh mate, id change the filter, plugs and sort them leaking manny seats then relog to see.
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