Date: Tue, 22 May 2001 22:35:10 -0700
Reply-To: Karl Wolz <wolzphoto@worldnet.att.net>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Karl Wolz <wolzphoto@worldnet.att.net>
Subject: Re: Fuel Injection (Long)
This is not quite, but very nearly, as good as a trip report!
Karl Wolz
----- Original Message -----
From: "Mike Finkbiner" <mike_l_f@hotmail.com>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, May 22, 2001 8:38 PM
Subject: Re: Fuel Injection (Long)
> Mark (and all of the others that have contributed) -
>
> To re-cap, I've been getting poor mileage and power on a new Boston Bob
2.1
> l engine with the longer duration cam and polished heads. I have a
> Digitool, and the readings look in line with Darrel's specs, and not very
> different than the old engine.
>
> #3 cylinder is only 110 psi, the other 3 are 130-140, and the fuel
pressure
> regulator is about 4# high at idle. I have put about 1200 miles on the
> engine, mostly on 55 mph highways.
>
> A mechanic who ran an emissions test said that the CO looked OK but the
> hydrocarbons are high, probably because of the cam. Mark and a couple of
> others have suggested that it's not the cam, but the fuel pressure
regulator
> (FPR) or the air flow meter (AFM) not properly adjusted.
>
> Several people suggested that we get the valves dialed in and see if that
> helps the compression.
>
> Since last we spoke, there have been a few developments.
>
> I tried running it with the idle stabiliser disconnected - no difference,
> but it was good to learn how to test it.
>
> Leaning out the mixture using the AFM seemed a good bet, and one thing I
did
> notice using the digitool was that the warm idle reading on the AFM was
> ~1.65. Darrel's notes suggest 1.5, so I opened it up, marked the current
> location, and turned the gear wheel 2 clicks counter clockwise. Now the
> warm reading is ~1.5, and I seem to have more power.
>
> Another area that was brought up was engine vacuum. If it isn't strong
> enough, the FPR will have a higher pressure reading.
>
> My mechanic adjusted the valves today (1/4 turn in?) and measured the
vacuum
> before and after. About 6.5 psi before, and about 8 after.
>
> Mark says that should be about 11-13 psi, so there is something wrong.
> There don't appear to be any vacuum leaks on the new hoses.
>
> One possibility is that the valves have to more thoroughly seat before the
> vacuum will come up. We plan to run it for a week or so and re-test the
> vacuum. I need to get it out for a run to see what the mileage is now.
>
> Now that the valves are adjusted, another thing I hope to verify is how to
> check the CO using the O2 sensor. Mark says that .5 volts = 5% CO, so I'm
> assuming that I can warm up the engine, shut it off, disconnect the O2
> sensor, connect a meter, re-start, and read the idle O2 off the meter.
Then
> I could use the idle CO screw on the AFM to adjust it.
>
> My digitool shows it bouncing from negative numbers to .8 or so at highway
> speeds, so I think it's working OK, but it would be nice to know.
>
> I'm hoping to talk to Boston Bob tomorrow to see if he has any other
> thoughts, and I'll keep reporting on what's happening in case any of the
> rest of you have similar problems.
>
> Darn this gets complicated!
>
> - Mike Finkbiner
> '87 Westy
> Moscow, Idaho
>
>
>
> >From: Mark Keller <kelphoto@islandnet.com>
> >To: Mike Finkbiner <mike_l_f@hotmail.com>, Vanagon List
> ><vanagon@gerry.vanagon.com>
> >Subject: Re: Fuel Injection
> >Date: Wed, 16 May 2001 22:10:32 -0800
>
> >Mike,
> >
> >Well, if your low on the #3 cylinder that may would have to be worked
> >out first. If you said 4 lbs high, as in 29 + 4 = 33 lbs at idle with
the
> >vacuum hose connected and your getting around 12 inches of vacuum you
have
> >a problem with the pressure regulator as that's over half of the range.
> >29- 36 is operating range of high to low load or vacuum -- not a
tolerance.
> >If you have 36 + 4 =40 lbs at the above conditions you >have a bigger
> >problem with the pressure regulator.
> >
> >I don't mean to sound harsh, but I believe that 4 psi at idle is enough
to
> >put your HC up. Mine run at 50 ppm HC on the lean side but ok. The other
> >thing is you don't mention attempting to adjust the idle air bypass, aka
CO
> >adjustment. This could also be out of adjustment. Most people myself
> >include use the O2 sensor output voltage to set CO since there is nearly
a
> >exact correlation i.e. .5 volts =5% CO etc.-- this tip is in the Bosch
Fuel
> >injection Book by Probst. And it really matters what vacuum your getting
> >at idle. BTW I have a spare fuel pressure regulator for what it's worth
you
> >can try it out.
> >
> >Also while were here, the first thing that should be done is to set the
> >spring tension or verify it by looking for an O2 sensor output reading in
> >the .5 volts- .7 volts range while the engine is at 3000 rpm. This is
also
> >covered recently, but its' mainly moving the geared wheel under the afm
> >cover. Once the spring tension is right, check the settings.
> >
> >BTW, the O2 sensor is disconnect from the computer in these scenarios.
I've
> >had the 4 gas analyzer done too, but using an O2 is probably is just as
> >good.
> >
> > You didn't mention if you had read the posts I referred to. Lilley is
> >the one who stated that High HC at idle in his own van caused him to fail
> >emission as was due to high fuel pressure because of a cracked vacuum
line
> >not the cam as you suggest.
> >
> >If your engine is warm the idle stabilizer in not operation, it only for
> >cold engine warm up. The idle stabilizer in fact adjusted by
> >disconnecting it, and then adjusting the idle manually.
> >
> >I wrote this kinda quick, so email me if something is unclear.
> >
> >Sincerely,
> >Mark
> >
> >Mike Finkbiner wrote:
> > >
> > > Mark -
> > >
> > > It's an interesting problem, and probably has several components. The
> >engine is still tight, and #3 cylinder is reading only 110 psi, so we
> >probably need to adjust the valves, but the rhythmic surging at steady
> >speeds really puzzles me.
> > >
> > > The high HC at idle is probably from the longer duration cam that Bob
> >put in. This engine has the ported and polished heads with the Lilly cam
> >that is supposed to provide more grunt without sacrificing reliability.
It
> >will be nice if that turns out to be true!
> > >
> > > The mechanic who ran the emissions tests said they looked good other
> >than that. There is currently no cat in the system.
> > >
> > > Another listee suggested disconnecting the idle stabilizer
temporarily.
> >I also have a new Temp II sensor. They will be a lot cheaper to check
than
> >ordering a new fuel pressure regulator.
> > >
> > > Current plan is to disconnect the idle stabilizer before I take a 100
> >mile drive on Saturday, then check the valves early next week, and
replace
> >the Temp II.
> > >
> <SNIP>
>
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