Date: Sat, 20 Jan 2007 12:05:28 -0800
Reply-To: Michael Diehr <md03@XOCHI.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Michael Diehr <md03@XOCHI.COM>
Subject: Re: Ping/Knock/Detonation
In-Reply-To: <000701c73cc6$b831a180$6400a8c0@MASTERPC>
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
The rebuild & install was done by a shop (who I won't name but I hear
is of extremely dubious reputation I'm told -- I was aware of that
going in but a move forced my hand) and I have no idea what they did
or did not do when installing the 2.1 into my 85. I believe that
when I got the rebuild home, I measured the timing at idle as per
bently (DIS disconnected etc.) and it was spot on. However, that
was 4000 miles ago.
Anyone on the list have an opinion as to how much total time pinging
it would take to fry my engine? 1 second? 10 seconds? 10
minutes? Should I just assume the engine is toast, find a new
mechanic, drop the van off, and fly home? :-) Anyone know when the
Zetec conversion will be CARB approved?
On Jan 20, 2007, at 11:10 AM, Dennis Haynes wrote:
> Did you convert to the cooling system with the oil cooler to also
> cool the
> pistons? Detonation is extremely speed and load over time
> sensitive. The 1.9
> FI system should not be a problem, both use the same injectors. Is the
> timing set to spec or slightly advanced? Get it set back down. Make
> sure the
> vacuum retard on the distributor is working to reduce the timing
> during part
> load to reduce the peak flame temperatures. Pinging actually occurs
> long
> before you hear it. While pinging, you working at busting rings,
> melting
> pistons, and burning valves or even cracking heads. This is where
> EGR could
> be helpful but the Vanagon does not have it.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> Behalf Of
> Michael Diehr
> Sent: Saturday, January 20, 2007 1:02 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Ping/Knock/Detonation
>
> I'm finishing up a long (3K miles) road trip and the van has been
> running like a champ (for the first time ever, wahoo!). However,
> I've noticed a problem with pinging (aka knock aka detonation).
> It's very particular -- it only happens at 1/2 throttle or higher at
> 3200 thru 3500 rpm, even on 91 or 92 octane gas. Happens most of
> the time -- only exception seems to be at temperatures of 30F and
> lower at 3000F altitude or higher, which seems very consistent with
> it being ping (heat & pressure related).
>
> As far as I know, the timing of the engine is good at idle, but I
> doubt that the advance has ever been tested.
>
> This is a 85 westy automatic with a newly rebuilt 2.1L block
> installed (about 5k miles post rebuild). It has the stock 1.9FI
> system, including a rebuilt computer & distributor & afm.
>
> It seems weird to me that the RPM range is so specific -- it really
> only does it at that particular RPM range. Any ideas? Bad
> distributor advance? Flat spot in the AFM? 1.9L FI system not
> well matched to a 2.1L block?
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