Date:         Thu, 11 Sep 2014 20:58:14 -1000
Reply-To:     "SDF ( aka ;jim lahey' - Scott )" <scottdaniel@TURBOVANS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         "SDF ( aka ;jim lahey' - Scott )" <scottdaniel@TURBOVANS.COM>
Organization: Cosmic Reminders
Subject:      Re: Engine miss
Comments: To: Dick Wong <sailingfc@DSLEXTREME.COM>
In-Reply-To:  <!&!AAAAAAAAAAAYAAAAAAAAAOt/xdRkfLlAqIF53JVUnbzCgAAAEAAAAGtSbB78UhFDjl58L1lAumQBAAAAAA==@dslextreme.com>
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TPS ....
fwiw...I just had a real issue with one ..
I think it might be the first TPS I have ever replaced, including
working on cars and vanagons full time for a long time.

the tests that one can do on a TPS didn't 'really' reveal anything .
The symptom in this case was it would run fine cold.....but once 1/4th
warmed up .
it could not do over 5 % throttle without racing and dying, racing and
dying.
Checked and tested 'everything' .
in the end it was the TPS.
I'd at least consider that yours could be acting up.
without a device to measure air directly, like an AFM or Air Mass Meter ..
the TPS is pretty important.

On 9/11/2014 8:19 PM, Dick Wong wrote:
> No AFM.  Vacuum line to the ECM & fuel pressure regulator, intake air temp sensor and throttle position sensor. I copied the wiring when rebuilding the harness (which was not the same as the Bentley schematic).
>
> -Dick-
>
>
> -----Original Message-----
> From: Neil N [mailto:musomuso@gmail.com]
> Sent: Thursday, September 11, 2014 8:53 PM
> To: Dick Wong
> Cc: vanagon@gerry.vanagon.com
> Subject: Re: Engine miss
>
> Does this version Digifant use an AFM? If so....
>
> Faulty portion of resistive strip in the AFM?
>
> tencentlife on thesamba.com posted a great simple check for AFM voltage dropouts while the engine is running.
>
> Neil.
>
> On 9/10/14, Dick Wong <sailingfc@dslextreme.com> wrote:
>
>> Now that Blaze is back on the road, I get a miss/hiccup when moving
>> with no load on the engine.  I've only noticed this in fourth gear and
>> have not tried it in any other gear yet.
>>
>> Typical situation: In fourth gear, level ground, steady speed.  While
>> in this mode, the engine will suddenly lose power for several seconds,
>> then recover.  It's not a sputter, it's a sudden loss. No dash lights
>> illuminate, tach is steady, no CEL. All this happens in the 1800 to
>> 2800 rpm range (approximately).  I've never experienced this before.
>> When accelerating or decelerating through this rpm range, it never
>> happens, only when at a steady speed.  At freeway speeds, 3500 - 4500
>> rpm, I don't see this issue.
>>
>> Digifant (023906023), 2.5L, 5 cylinder, new Bosch plug wires, new
>> Bosch dist. cap, new Bosch rotor.
>>
>> Since this is basically a Eurovan setup, that's my next stop.
>>
>> Any ideas?
>
> --
> Neil n
>
> Blog: tubaneil.blogspot.ca
>
> '88 Westy http://tinyurl.com/c8rlw6p
>
> '81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/
>
> Vanagon VAG *Gas* inline-VR Engine Swap Group:
>
> http://tinyurl.com/d7gd5ej
>