Date: Sun, 5 Aug 2012 11:57:32 -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: Double checking my stumbling problem
In-Reply-To: <CAFnDXk3ynVLSv7GCier=ZhiqT_9=8Bx5CUWEL3aUiGCMP-f1cg@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Condider also the fuel pressure regulator.
I seldom find a bad one, and once in a while I do.
it 'could' be your fuel pump..
and I would automatically put together " only 27 psi = needs a new
fuel pump"
Give you an example...
roached out air-cooled 81 westy that I would nomrally never touch.
the only other local vanagon guy plus a local air-cooled VW guy can't
get it to run on all cylinders,
and they have spark, fuel being injected they say, and compression and
they thought a little about air intake leaks, but couldn't solve it.
so that means I have to/get to work on the thing.
I spent good time on fuel pumps, filters, feed from the fuel tank, fp
regulators etc.
I have it running on another source of fuel finally.
I put my FP guage on it , the pressure testing port is on the left side.
I have a running engine with zero pressure showing on the gauge.
or maybe 4 psi.
Overnight I thought of ...maybe there is a blockage on the fuel rail
somewhere ..
( it's not a 'twin' layout like the waterboxer has..
and this is yet *another* example of VW upgrading a weak layout or system..
on the air-cooled the fuel rail is a single long route.
fuel comes in the right side, two injectors branch of there,
then it goes to a cold start injector in the plenum, though that,
to the left side where there are two injectors and a fp pressure testing
port, then to FP regulator, than back to tank.
I figured maybe blocked along that route somewhere.
Sure enough ...rusty large flakes of junk at the cold start injector
junction ..
that junk was actually keeping fuel pressure up for the right side
injectors,
and allowing very little pressure at the left side injectors.
I clean that out ..
finally ....34 psi at the fuel pressure testing port.
anyway ...I wouldn't jump right to 'fuel pump' , but I'd sure consider it.
fwiw ...if you run one against a totally blocked off line..
like it has fuel in it for sure and it's pumping as hard as it can,
it'll do 100 psi , not that I do that test very often.
"It's just a blocakge or leakage of fluids or electrons."
Scott
www.turbovans.com
On 8/5/2012 8:42 AM, Jim Felder wrote:
> Fore several weeks I've been chipping away at a poor running 2.1. I've
> swapped out this and that, and to me it acts like a bad fuel pump that
> delivers enough pressure to start and idle but not keep up with the demands
> of acceleration, hills, etc. And it's getting worse.
>
> I was finally in town long enough to put a pressure gauge on the system and
> I see it measures 27 psi. The Bentley says that 30 to 36 is normal range. I
> know somebody is going to say "well, if that's what it says..." but I
> wanted to hear from more experienced mechanics before I ordered a fuel
> pump. I have been burned before on this. I invested a year of
> troubleshooting and lots of money in a 2.1 that behaved similarly before I
> fixed the problem. I don't want to go through that again.
>
> If anyone with experience says "mine's lower than that and it runs fine"
> then I will keep looking. If the consensus is that it just won't operate on
> 27 psi, I'll order a pump.
>
> thanks,
>
> Jim
>
| 
