running lean
 

Just been on the rollers today and im well happy with the results apart from the fact im running lean.

im running 12.5 -12.8. now what would be the best way to get this figure down without getting a remap just yet.

would an safc help. or would you suggest uprated injectors, fuel pump. fpr. or is this not worth it?

all help appreciated.

Before we can make any sensible, considered suggestions, we need to know what sort and age of car you're talking about, along with mods/state of tune. Can't help you if you don't help us.

i knew you would say that.

v3 sti. mods so far = headers, dp, decat, vf43, fmic, 08 wastegate solinoid. siicon intake pipe with blitz filter

Oh, blimey. Well, there's your answer. You're running a stack of mods that need mapping and, given that you haven't actually mentioned an aftermarket one, on an ECU that can't be mapped. Turbo, fmic, induction kit, turbo pipe and headers and you're wondering why it's lean.

There's not much point messing about with an AFC on that setup, you need a proper ECU mapped properly. Are you actually monitoring AFR and det when on the road?

If the AFRs above are accurate and taken on boost you will soon need a new engine if you continue to drive the car on boost.

You could be in a house anywhere so I cannot recommend you to anyone in your area but I suggest you seek assistance sooner than later unless the figures you quote are spurious or you have funds saved for a new engine.

Basicly you need an ECU and proper remap.

im in cardiff.

based on the graphs from several cars on the dyno runs, alot were running lean. cars that had been mapped by repitable mappers were even lean after a month, i am in talks with someone now trying to get advise and i am pulling apart the block on the weekend anyway just to check it all and replace belts :thumb: bit extensive i know but needs must and all that.

If you're implying that the AFR monitoring used on that day was somehow inaccurate, and all the cars tested were reading on the lean side, you might be right but it's impossible for any of us here to know, and thus the only thing we can do is assume the worst case scenario, which is that your car *is* running lean.

Pulling the engine apart right now seems to be a bit of a counterproductive idea. Seems to me you'd be far better off leaving it in one piece until it can be looked at by a competent mapper (or you can borrow a wideband AFR meter and check the ratios yourself).

im not implying that it was all incorrect and believe it or not even though i know others are out i am still treating mine as being right. im not just ripping the block apart for nothing. and to be honest i am doing it because i have a suspected headgasket faliure. but i wont be sure till its stripped (im 99% sure its started to go)

i am taking on your advice and i am also going off what JGM has been saying on the other thread as well.

i will try and get wideband with afr meter to see what mine is actually bringing up.

i know you all mean well and you are trying to help which i appreciate and i know i need a remap but i will get one eventually but i cant right now as i have other issues. so i am trying to do what is right for me and thats why i am asking for other peoples help.

No uprated fuel pump?
Wondering if the one you have is a little "tired".

Tony:)

Much as above. It makes no sense to take the engine out just because you got lean AFR figures on a rolling road when these figures may be suspect becuase others had lean figures too.
Get your AFRs checked and if they are lean get the car remapped. Even if you have been running lean there is a good chance you have caught it before it does any damage but it must be a priority right now to check your AFRs accurately.

I would suggest you get the AFR's and map looked at before you worry about getting the headgasket replaced. If you do replace the HG and you are still running lean and possibly detting, that just seems counter productive.

ok. there are other reasons why i want to take it apart. i am doing my headgasket full stop. i need that done before i sort out any fueling issue i have, and yes i am taking it apart but that is to check what is in the block. see if it has been up rated in any way shape or form. plus im thinking about doing pistons rods and bearings while i am there. then once this is done i can then work out about getting the car mapped.

if it has done a headgasket.. you replace it and drive as is, it will probably do it again..

it is possibly detting and hence done the head gasket and may not be lean for a mapped car but it is lean for a standard map with bigger turbo and other mods etc.

From what I have seen the reading on that RR appears around just under 1 AFR leaner than the car is.. thats from more than one car, rather than just one.

Simon

i think what done the headgasket was the fact my radiator split and my car over heated slightly.

i will get all this changed and running. then once its all working again i will be in more of a position to get the car looked at and mapped.

Has your head gasket gone? If the head gasket is gone you will spew out coolant on boost and there will be HC products in the coolant which can be detected by analysis.
Replacing the head gaskets without adequate cause seems like a lot of work for no gain and from your thread it is somewhat unclear as to what you are trying to achieve because it would appear that the cars in general were running weak AFRs which suggests a Lambda monitoring issue at the facility you used.

The point that's now been made by a couple of us is that it would probably have been better to keep your engine in one piece until you've established beyond doubt whether your car is indeed "running lean", or whether that was, to any degree, an aberration in the rolling road you visited.

TBH it's getting difficult to work out what you're trying to achieve here - possibly because, as you seem to suggest, you have two separate threads on the boil. If so it might not be a bad idea to ask the mods to amalgamate them so anyone attempting to work out where you're at has all the pertinent info a flick of the scroll wheel away.

Until then, I must admit it's reassuring to see I'm not the only one struggling a little bit to work out why you're going about things in the order you are.

Why spend lots of money on pulling the engine and replacing bits but not remap? Seems like a very false economy to me.

Detting has probably caused your headgasket and will do exactly the same again (or worse) when you bolt it back together.

Drive off boost til mapped.

i have checked and yes i am boiling over on boost thats why its coming apart and why not check everything while i am there. I am loosing water due to boiling over. i did a block test to test for hydrocarbons in the water and ok i didnt have a bright green final fluid but it did start to turn green, i have checked everything else and there is no leaks when the system is pressure tested so i know its headgasket.

the other thread is not my thread, its the rolling road thread when others are having issues with running lean. i posted this before someone said anything on there. im only asking for info in regards to my running lean situation. but i will get it back on some other rollers to test what is right and what is actually wrong. but after i do my headgasket as i dont want that going any further.

as just said. i have hg failure and this needs to be sorted. killing 2 birds with 1 stone as they say!

The AFR's you quote are perfect for a well mapped car, but as above if it's a standard calibration designed for a catalytic converter, then you'd be expecting it a lot richer (to maintain cat temperature).

are you sure because everyone seems to think other wise! i was told between 10-11 not 11-12.

i will take my ecu out on the weekend also. to see if there is a daughter board in it.

Like I said, on a standard (cat) calibration it's relatively lean so something isn't right/requires a custom remap.

I don't really want to get involved with a "what is the ideal AFR" debate, you only have to look at proper engineering reference from people like Bosch to find that out. Different tuners do things in different ways. :thumb: