S2 running rich
Discussion
Bill,
Mine seems to run very rich too. I too replaced the pressure regulator with an original but I don't think it made a difference. I've also replaced the coolant temp sensor but that didn't have any impact. To answer your question on the MAFs, the screw is for an air bypass, so it's anti-clockwise to raise that 'needle' and let more air through around the flapper, giving the engine more unmetered air and leaning it off. It only really affects the idle mixture though because it's volume in proportion to the metered air drops off substantially when you rev the engine.
Do you smell the richness? I certainly do and I get popping in the manifolds, which may indicate a valve clearance issue that means I'm only running on 5 cylinders and flowing neat fuel out on the 6th?
Cheers,
David
Mine seems to run very rich too. I too replaced the pressure regulator with an original but I don't think it made a difference. I've also replaced the coolant temp sensor but that didn't have any impact. To answer your question on the MAFs, the screw is for an air bypass, so it's anti-clockwise to raise that 'needle' and let more air through around the flapper, giving the engine more unmetered air and leaning it off. It only really affects the idle mixture though because it's volume in proportion to the metered air drops off substantially when you rev the engine.
Do you smell the richness? I certainly do and I get popping in the manifolds, which may indicate a valve clearance issue that means I'm only running on 5 cylinders and flowing neat fuel out on the 6th?
Cheers,
David
Loach1 said:
Do you smell the richness? I certainly do and I get popping in the manifolds, which may indicate a valve clearance issue that means I'm only running on 5 cylinders and flowing neat fuel out on the 6th?
If you have a misfire or other substantial problem on one cylinder you may be able to pick up a difference in header temperatures. This is easy to pick up in the first few minutes after a cold start, but can also be seen using an IR thermometer. As a last resort you can just touch a piece of plastic to the header and see how quickly it smokes - plastic cable ties are ideal for that.GreenV8S said:
If you have a misfire or other substantial problem on one cylinder you may be able to pick up a difference in header temperatures. This is easy to pick up in the first few minutes after a cold start, but can also be seen using an IR thermometer. As a last resort you can just touch a piece of plastic to the header and see how quickly it smokes - plastic cable ties are ideal for that.
That's a great idea! I'll give it a shot. Thanks for that tip.Gassing Station | S Series | Top of Page | What's New | My Stuff