Can Hot Start button be used for test?

4 replies to this topic
  • divebobber

Posted December 01, 2008 - 09:03 PM


I have a 2000 426f. Does anyone know if the Hot Start button provides a lean condition throughout all throttle settings, or just at idle? The reason I'm asking is, I'm wondering, if it leans things out throughout the throttle range would it be useful in determining the need for leaner jets? Along with that thought, would using the choke do the same thing in the other direction? I.E., if it runs better with the choke button out, would that not indicate you should jet richer? I've tried searching for this question and haven't found it, so here it is.

  • BC3

Posted December 01, 2008 - 09:09 PM


It would have to be VERY rich or very lean.....

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  • grayracer513

Posted December 01, 2008 - 09:53 PM


No, it would not be a valid indicator. It has less effect the more you open the throttle. However, if the engine runs better at idle or off idle with the hot start pulled, it would indicate a very rich condition, such as high float level, etc.

  • divebobber

Posted December 01, 2008 - 10:17 PM


Thanks for the replies, guys. Just a thought.

  • motojoe_23

Posted December 03, 2008 - 12:37 PM


In my experience, yes, somewhat. But you have to really know what you are looking for and symptoms.

It wont "fix" the issue to the point you go "oh it was lean", or "Oh it was rich" because it now runs right. It can improve or make it worse to a small extent, and f you know what you are looking for it can help diagnose.

But you still have to know what you are doing in the first place.

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