Date:         Thu, 15 Apr 2010 07:59:25 -0400
Reply-To:     B Feddish <bfeddish@NETREACH.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         B Feddish <bfeddish@NETREACH.NET>
Subject:      Subtle hesitation- driving me crazy...
Content-Type: text/plain; charset="us-ascii"

I'm still trying to work the bugs out of my new engine setup.  What I have
now is 2 things, not as much power as I would like and a subtle hesitation.
OK, I can learn to live with the less power, my old engine had the timing at
10 BTDC and the vacuum hose disconnected.  This was fine since the engine
was coming out and I did not want to investigate further.  I want to run the
new engine at factory spec, OK, timing at TDC, but I want the vacuum hoses,
idle stabilizer, etc. connected. Following both Dennis Haynes's and Gary
(the engine builder's)  advice the engine should really run fine at factory
specs.  My biggest issue from the onset was a burnt connection in the
distributor cap.  It was bad. There was a noticeable difference when I
replaced the wires, cap and rotor.  The current issue is there is a very
subtle hesitation when accelerating.  Subtle enough that I notice it but a
regular mechanic might not.  This happens when the engine is cold or hot. I
have swapped out the AFM, no difference, I have swapped out the ECU, no
difference, I have replaced the vacuum lines, no difference.   Now the van
will run fine at a higher timing advance but we don't want to do that.  Some
have suggested the fuel injectors but keep in mind, the old engine with all
the exact same parts ran fantastic with the timing advanced. I'm taking good
power and great gas mileage and no hesitation.  I'm leaning towards the
distributer. Could this be the cause? Wouldn't non-functioning vacuum
advances and/or retards cause this problem? Is there a way to test these
things? I see ways to test the electrical connections but not the vacuum.
And if my vacuum retard is not working how do I know I have the timing right
at 850 RPM's?



I'm all ears on this one. I'd gladly take it to a mechanic but this is one
of those cases where I could get a worse running van back, it's happened. If
I take it to someone I would  like to be able to point them in the direction
of what to look for.



Thanks,

Bryan