Jump to content

Running lean on warm starts


Recommended Posts

My car starts as it should when cold but if i drive for a while then start it within the next hour or so it will idle a bit rough. Nothing too bad but noticable and the AFR car be between 17-19 :/

If i tap the throttle it comes right down and once i get moving for a bit it will slowly get back to normal. Its really strange if i sit with the engine running and let it get hot it never seems to go past 15.5 so im confused why it happens on warm starts.

Any ideas?

Edited by Patches
Link to post
Share on other sites

Mine does exactly the same, but probably worse, I can start it first time but if I turn it off and try and start it again it doesn't start or it does the lean and rough idle as you described. I'm running emanage blue by the way.

Brendon

Link to post
Share on other sites

I run 16 + A/F on idle at operating temp. It actually burns more cleaner, aswell as being more fuel efficient. Any leaner then 17:1 A/F and it tends to eventually decrease the idle speed or cut out. If you don't have a catalytic convertor then it is fine to run this lean on idle. The car will run stoich (14.7:1) on the stock ecu so the cat does not overheat from the hotter exhaust gasses.



It sound's like maybe possibly a sensor is starting to go duff causing this issue on your car, but as mentioned, the A/F is more crucial when the car is on load.


Link to post
Share on other sites

It's due to the stock lamda sensor not getting up to temp after the restart. If you drive more gases are produced so the sensor gets up to temp.

So would a new lambda help as mine just started doing this some time ago?

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...