Running lean in idle

[aznturboman]

Howdy everyone,

So today I was going to drive my typhoon but when I started it today it revved to almost 2000 RPM and then went down to around 1000 but at the same time my stock o2 and wideband was showing lean conditions around 17+

I have checked all my vacuum lines and couldn't find a leak, fuel pressure is holding, I disconnected the o2 sensor to see if anything would change and nothing changed.

What else could cause this problem?

Please help
-aznturboman

 

[E.Murray]

Re: Running lean in idle

Maybe a reply (no matter how useless...) will bump you back to the top to get some smarter people interested. I just added a WBO2 and had a similar issue. Mine was showing 17+ with just a slight throttle input at low speed cruising. I was also having a stuttering under boost, which led me to check the plugs. They were all a little fouled and gapped a bit wide. Just tonight, I put in fresh plugs gapped to .028 and am now show 12.5-13.5 under the same conditions that used to read 17+. The stutter is also gone. I think it was a misfire due to weak ignition causing mine. Are you sure your ignition is solid?

 

[STAGEUP]

Re: Running lean in idle

List your mods and chip or tuner tool. It would be a lot more helpful

 

[aznturboman]

Re: Running lean in idle

Truck mods
Kenne bell A2A
RPM's 3 in exhaust w/ no cat.
afpr
ram intake
NGK ur6 gapped .030-.032
forge motosport WG
Velosyty chip for stock injectors
Scanmaster from Turbo Tweak




I'll check my plugs tomorrow to see if they are fouled. Should I make the gap smaller?

 

[Peter]

Re: Running lean in idle

At cold start, revving to 1500 or 2000 and then dropping back to 1000 or less is usually normal. I don't think a SyTy will idle at 17:1 AFR, so don't believe the readings. It takes some time, up to a minute or so, for an O2 sensor to warm up and read correctly. There is a heater coil in the O2 sensor that minimizes the warm up time. If power is not supplied to the heater, it will take longer.
Closing the gap won't do much at idle. .030 or .032 is fine at idle. Closing the gap helps when boost causes misfire, "blowing out the spark", as they say.

 

[aznturboman]

Re: Running lean in idle

okay guys so I got the idle to be good again but idk how this worked.

So I went out to start the typhoon today to see if the problem still persist and today I noticed that the exhaust smelled rich but for some reason the gauge was still reading 17+. So I thought what the heck I'll turn down fuel pressure and all of a sudden I started to get numbers 14-15 afr's again and now its running good.

How could turning down the pressure make it run normal again?

 

[Darin]

Re: Running lean in idle

Could there be an air leak in the exhaust before the o2 sensor? Oils be air getting sucked into the exhaust.

Remember, they read oxygen, not fuel.