Date: Sat, 17 Oct 2009 15:41:47 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Start Idle Issue
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re
"The problem came about after the fuel injectors were swapped
out. "
ah guys.........
maybe 4 rebuilt or cleaned injectors have nothing to do with it .......
and I can help saying about 50 times...........
if you have a bad injector, yes, get a good used one in there, invest in one
rebuilt one, or a new one if you can find one.
but do not, replace all injectors as a 'blanket fix'.
what I would do if I just got into this van or job, knowing that it only
started doing it when all 4 injectors were replaced.......is hang the
injectors out where you can see them........and check their spray pattern.
I would even say that injectors work amazingly well, given how often their
spray pattern sucks.
I went through 10 waterboxer injectors to find FOUR that sprayed like the
picture in the Bentley book. That van passed a smog check A + a couple of
weeks later too.
I would regard
"If I
> give gas, the engine seems to flood and try to die."
and THE SYMPTOM you are working on .......nothing about rough idle
cold.....just - when I give it gas, cold, it floods and dies.
Surely ecu temp sensor pops into mind for that.
have you checked yours ? .....see if resistance is about in line with the
chart in Bentley.
Very important to do that.
for sure oxygen sensor does not come into play until closed loop.
If the AFM does ........I've never heard that it's not involved in open
loop, let's say that.
As far as diagnosing anything ............in my experience you don't need to
know that about the AFM even.
it will run with the AFM not connected, fwiw.
I get bugged, because I see all kinds of parts through at, and installed on
vanagons ........
and what I don't see are.........attention to fine details.
I would even go far as to say that people are loosing ground sometimes by
replacing parts.
It's not in the parts !! it's in the adjustments, and the attention to
detail.
AFM's do wear out, for sure.
the normal symptom is uneven acceleration, uneven steady running, and uneven
deceleration. ' Mostly' that's what AFM's cause ..........'uneven' running.
If one is say 10 to 15 years old, it is suspect if there are symptoms
occurring that could be caused by a tired AFM.
When one is tired, there's no really a way around it , other than tweaking
inside the thing, which 'sort of works' , sometimes. Not recommended
really.
and also ........
there are 'for sure' no intake air leaks form when the injectors were
replaced.
See.........not only is there risk of loosing ground by installing more
parts than are needed that may be of questionable quality ......
there is also the matter of errors introduced during the process itself.
Like .......if someone doesn't put them in correctly ........
new parts isn't worth jack.
Sorry to rant, but I have just seen case after case after case...........of
where workmanship was weak, or 'the problem.'
90 % of what I fix, is just by careful inspection, adjustment, getting
something working again like it should, cleaning, lubricating, etc.
And 'it all adds up.'
if someone is wondering if their .........'whatever' is faulty ......and it
is not Clearly Known that ...........oh..........throttle switch is working
and adjusted properly, ecu temp sensor is about right, plug wires are
decent. timing is pretty close to correct ............oxygen sensor is
working , spark plugs are correct ........fuel pressure is correct. etc.
as an analogy, What I am seeing is that vans are getting new tires, when
what they really need is correct tire pressures, decent shocks, and front
end decent and aligned at least decently enough. It's not in the parts -
it's in the workmanship.
I find spark plugs installed incorrectly all the time.
And .......spark plugs are the last part on a vanagon engine likely to give
trouble. They hardly wear. If the right plug is installed, with correct
plug gap, and anti-seize compound on the threads, and torqued properly
.......
a 'tune up' is a waste of money.
bosch tune up parts in vangaons last just nearly forever.
anyway ..........what I would suggest, as always is ...........check the
basics.
When someone comes on here and says.......I have checked very carefully the
following 25 things....
and they are in spec, or at least good enough to work right .......now we're
talking.
a waterboxer engine should rev out, and drive with full strength ( though
you should be gentle on it for the first 5 minutes or so ) from dead cold.
It should start fairly instantly, with a medium fast idle.
and .........seriously, letting an 'engine warm up' is a horrible thing to
do to it. Engines do not warm up very well without load.
You should start it gently as you can, then drive gently within about a
minute or so, even less.
don't use premium, fuel !
and please don't ask why - it 'burns slower' is the answer.
also ........
waterboxer vanagons must be driven to fully warmed up in the winter.
That means at least 20 minutes.
It's like this ........AFTER 20 minutes .............THEN the engine is on
OK operating mode,speaking about Winter here.
So during the first 20 minutes, ......
as far as I'm concerned, probably there's unburnt fuel getting into the oil,
There's acid going into the muffler and the engine oil.
I worked on an 87 GL.....
the driver said it started smoking badly so she shut it off. ( a cautious
approach ) .
I was suspecting an injector leaking perhaps ..........
I pulled plugs before cranking, just in case there was a cylinder full of
gas.
At my shop I got it running .....
and nothing really that wrong about the engine, fuel system, tune up stuff,
muffler etc.
It worked perfectly for me actually.
What I said to her was 'I bet you drive this van 3 blocks to the Food Co-op,
and back, right ?" ..
that was it.
you need to have things ........a bunch of small ones, in spec,
........don't sit around warming it up, and drive it to fully warmed up. If
it doesn't get fully up to temp fairly quickly, fix that.
I am finding, btw............2.1 waterboxer throttle switches that will not
adjust, or won't adjust far enough.
It's a very weak design ........
the eccentric that's used to adjust the switch, is a small aluminum very
soft metal cam, on the underside of the switch mechanism .........
there is a cover there, but I doubt it will keep road salt out really, for
20 + years.
I got one 'lifted up' from the plate it lives on recently, and was able to
get that aluminum cam moving again.
the allen screw hole, to adjust the cam with .......is aluminum, seems to
me, and if it can't move smoothly .........very easy to harm that delicate
aluminum screw thing there.
I mention all this on the throttle switch because I find them out of
adjustment all the time.
last one I fixed............the throttle cable had too much tension......and
throttle plate could not return fully to idle.
IT's all in the Details !
I strongly recommend only Bosch and german parts be used on vanagon engines.
always start with the basics.
there's no sense wondering about rough idle if one cylinder has 90 psi
compression and the other 3 have 135. You can live with that for a
while.......
but .........check the basics first.
I could right a 6 volume book about the things I've seen .......
like a new rebuilt carb on an engine that had spark plugs with Missing
electrodes !
like a 400 dollar rebuilt carb on an engine ......I get into it because it
doesn't run right - the distributor was disintegrating and full of aluminum
...and that was expensive profession work too.
you can save so much grief and $ just checking and fixing the basics, and
the details. It doesn't usually cost much to fix intake air leaks for
example.
I'm not finding many shot air intake boots, but always check that. I'll bet
there are throttle bodies that are not screwed down tightly to the air
plenum out there. On and on like that - and lube everything that moves.
all right !
may all have great success with their vanagons and diagnosing them !~
----- Original Message -----
From: "Jeff Michal" <jeffmichal@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, October 16, 2009 11:26 AM
Subject: Start Idle Issue
> Hi everyone. Could use some public review of a problem I'm having with my
> 90 GL Vanagon. It's got the stock 2.1 liter engine, ~130k on it.
>
>
>
> I am seeing an issue with the engine idle immediately after start. The
> engine seems to run rough for a short time, the amount of time seems
> dependent on the engine temperature. If the engine is warm, the rough
> running lasts for 1-2 minutes. If the engine is cold, the time is pretty
> much 1 or 2 minutes after the engine heats up to halfway to the LED on the
> temp gage. During this time, the engine is idling about 650-700 rpm. If
> I
> give gas, the engine seems to flood and try to die.
>
>
>
> Recently I have had to replace the throttle linkage and all 4 fuel
> injectors. The problem came about after the fuel injectors were swapped
> out. From what I know about the efi, it has a short period (1-2 minutes)
> where it runs in an open loop prior to engaging the mass airflow sensor
> and
> entering a closed loop with managed air and fuel volumes. It seems to me
> this open loop period is where the problem must be, but I'm not sure how
> to
> resolve it.
>
>
>
> Any ideas are appreciated.
>
>
>
> Jeff Michal
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