Date:         Mon, 18 Oct 1999 20:01:27 -0700
Reply-To:     "T.P. Stephens" <doktortim@ROCKISLAND.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
Comments:     RFC822 error: <W> Incorrect or incomplete address field found and
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From:         "T.P. Stephens" <doktortim@ROCKISLAND.COM>
Subject:      Re: Weird hesitation / power loss in '85
Content-Type: text/plain; charset="us-ascii"

> (1) At idle, the idle is rough. Holds 800 rpm+/-, but
>noticeably rough. (2) Around town, you just can't count on how far you'll
>have to push the accelerator to get what you want to happen to happen. At
>very low speed (<1800 rpm, i.e. pulling away from a stop) it might have NO
>power, requiring clutching up to 2500 or so in order to get going. Cruising
>at 35-40 mph, it feels like someone is behind alternately giving you a push
>or grabbing your bumper and pulling.  (3) At highway speeds, 3500+ rpm,
you can still
>feel the occasional hesitation but it's not usually a problem due to
>inertia. BUT, sometimes it gets to an extreme case that seems quite
>strange: with the pedal all the way down, the van starts losing speed as if
>the engine is losing power altogether, and perhaps in a way it is!
>
>The strangest thing to me is my workaround for the problem: all I have to
>do is turn the engine off and back on! It always starts right back up, and
>with no waiting period, we're in good shape for at least another 15
>minutes, often longer at this point. That's right: (1) smooth idle, (2)
>smooth acceleration, (3) 70-75 on the highway with no problem. Am I
>"rebooting" my van? I'm a software guy, so maybe this shouldn't surprise
me...
>
>More details:
>--  The problem is most likely to begin AFTER coasting down a hill in 3rd.
>--  While the problem is occuring, it generally responds to having the
>accelerator pushed all the way. For example, you're trying to accelerate
>and push the gas down halfway. Nothing really happens - just no response at
>all. Keep pushing, keep pushing, keep pushing, and when it's pretty much
>all the way down, YOW! Full steam ahead!
>--  Before the 3-cylinder problem was found, Scott did adjust the timing
>(in spite of it "not needing adjustment") as a troubleshooting measure. It
>made things worse, and he put it back.
>--  We replaced the O2 sensor. No help.
>--  I've been using 93 octane gas.
>--  California emissions.
>--  Fuel mixture has been adjusted.
>--  Idle control valve replaced.
>



ALL THE SYMPTOMS tell me to first check the air flow meter flap for
sticking. Let us know if that's it.
Doktor Tim
Maintenance Repair and Restoration of European Vehicles
San Juan Island, WA