Date: Sun, 14 Aug 2016 21:27:18 -0700
Reply-To: Scott - IMAP <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott - IMAP <scottdaniel@TURBOVANS.COM>
Subject: Re: Weird running issue with 86 Vanagon , tried dozens of things
In-Reply-To: <BAY405-EAS3787B7927A7A036248DEBC3A0110@phx.gbl>
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Excellent .
Won't be able to work on it for a while..
but when I do ....I'll use all this very good info.
the 'before it does it' time may not be a full 8 minutes.
but I think it's over one minute as mentioned .
ambient temps have been very high ...80F or above all the time it was
doing it.
Didn't have to drive it even ..just idle a few minutes
I know right where to focus next,.
thanks , Scott
On 8/14/2016 6:56 AM, Dennis Haynes wrote:
> For checking grounds it is not sufficient to just check the ring terminals
> and screw connections. The wires are now reaching a point that the corrosion
> can be so bad at the crimp for the connection to be bad and often the wires
> will actually break or disintegrate within the insulation even a few inches
> away for the connections. You have to test for stray voltages at the grounds
> for each of the sensors. There is also a connection point for grounds within
> the FI harness and this can go bad also. The reset indicates an O2 sensor
> circuit problem but for it to run normal for up to 8 minutes indicates there
> is more going on. Coolant temp at ~120 or above the ECU should be trying to
> go closed loop in ~1 minute. How is the O2 sensor reacting when it is
> connected? This will tell you something.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Scott - IMAP
> Sent: Sunday, August 14, 2016 1:24 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Weird running issue with 86 Vanagon , tried dozens of things
>
> The Presenting Symptom ..
> once warmed up ( takes about 8 minutes ) there is almost no throttle
> repsonse from idle, but if I shut it off and start it back up ..it's fine
> for a few minutes.
>
> I can even turn the key off in gear when when it does it, and it'll be fine
> for a few minutes.
>
> If I'm working on it back by the engine and it does this 'no throttle
> repsonse thing' and I just hold wide open throttle .....it runs very rich
> and may eventually clear out.
> Shutting it off and restarting fixes it every time, until it does it again.
>
> the Subject with this system is ..
> 86 Vangaon with brand new rebuilt auto trans ..rebuilt by German Transaxle
> of Bend , oregon. I don't think the trans has anything to do with it.
> it starts and runs cold just fine.
> The lopng block happens to be a 1.9 rebuilt engine with new reground
> camshaft and new lifters.
> Great compression, no intake leaks, starts nicely, idles just fine , goes
> farily well ...just has this one issue....once warm it just won't repsond to
> throttle until I turn off ignition and restart.
>
> have done the following ..
> tried several ECU's.
> ran two different distributors.
> tied two different known good Air Flow Meters, with and without adapter
> harness.
> Checked carefully that throttle switch is making contact at idle and WOT
> ..tested that clear to the ECU pins in the main harness.
> igniton timing is correct.
> compression is good. No intake leaks.
> installed a new Temp Sensor II.
> checked for shorted oxygen sensor wire.
> ran with and without oxygens sensor connected.
> Don't think it has anything to do with Idle Air Valve or control unit for
> it.
>
> I know it's not a clogged or restircted cat as I put a hollow one on for
> testing.
> Muffler is decent quality brand and new.
>
> I'm about to install and try out another Main EFI harness .
>
> Grounds ..I believe those are all ok as it's a fresh install and I
> generally fuss over every little thing I come across that needs attention,
> cleaning, tightening etc.
>
> I almost never put anything together without 'something' on every threaded
> fastner, electrical connection etc.
>
> so ..other than trying another 2.1 Digifant EFI which I have ..
> I am open to suggestions.
>
> thanks !
> Scott
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