Date:         Mon, 28 Nov 2016 20:32:44 +0000
Reply-To:     Michael Magnani <mfmagnani@SBCGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Michael Magnani <mfmagnani@SBCGLOBAL.NET>
Subject:      Re: 2.1 WBX Warm Start Troubles
Comments: To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
In-Reply-To:  <CY1PR20MB0029E6F6356DC13916C75A1DA0B20@CY1PR20MB0029.namprd20.prod.outlook.com>
Content-Type: text/plain; charset=UTF-8

To answer Dennis's questions:
The warm start problems came on suddenly.
Compression Check results:
Cylinder 1: 125 psi
Cylinder 2: 140 psi
Cylinder 3: 120 psi
Cylinder 4: 130 psi
Cylinder Leak Down Check results:
Cylinder 1: 25%
Cylinder 2: 15%
Cylinder 3: 20%
Cylinder 4: 25%
Idle Fuel Pressure: 32 psi
Cold Idle Vacuum: 13 Inches Mercury
Warm Idle Vacuum: 11.5 Inches Mercury
The following information is based on the readings of my Shoebox Electronix 8691V ECU Monitor:
 COLD. KEY ON

Coolant Temp: 1.35 VDC
Air Temp: 1.35 VDC
Air Flow Meter: 0.23 VDC
O2 Sensor: 0.41 VDC
O2 Sensor Ground: 0.02 VDC
KEY ON AT WARM IDLE
Coolant Temp: 0.11 VDC
Air Temp: 1.26 VDC
Air Flow Meter: 1.53 VDC
O2 Sensor: Variable between 0.2 and 0.65 VDC
O2 Ground 0.1 VDC
One question I have is: How steady should the Oxygen Sensor Voltage be when operating?
Thanks,Mike M



 

    On Sunday, November 20, 2016 8:19 AM, Dennis Haynes <d23haynes57@HOTMAIL.COM> wrote:
 

 I've been seeing this thread for a while. I have a few questions so that maybe I can be of help. Is this a problem that has been developing or is it long term? Was it gradual or sudden? Have you checked engine compression and done a leak down test? A bad intake valve can cause weird symptoms like this. 

If the engine and ignition system proves out and you get a rich enough mixture during warm start that you see black smoke after start you need to begin looking for leaking injectors and the temp sensor/wiring. 
After arriving in Florida last Tuesday I began having problems with Fun Bus. No idle, running rich. Rest ignition and would clear for while so I though O2 sensor. Check yesterday. Turned out just a bad connection at the Air Flow meter. Disconnected and Reconnected a bunch of times to wipe the contacts and it is now working fine. Look for simple stuff. 

For the adjustment on the air flow meter, it is only a small bypass around the flap door. It is only there for idle trim. It will not fix your starting problem. Hopefully your AFM has not been opened up and tampered with. 

Dennis


-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Michael Magnani
Sent: Saturday, November 19, 2016 6:15 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 2.1 WBX Warm Start Troubles

Per Zoltan's suggestion, I spent some time on the air intake system.I replaced the Fuel Injector seals.Checked the Breather Hose.Checked the Idle Stabilizer Hose.Removed the big hose between the Throttle Body and the Mass Airflow Sensor.Checked the torque of the Induction Tubes at the Heads. (New Gaskets last year).Checked the clamps at the Induction Hoses at the Air Box. (New Hoses last year).Replaced the Vacuum Hose at the Fuel Pressure Regulator.
I seem to have fixed the vacuum leak because my Fuel Pressure Gauge reads as follows:
Key ON, Engine not running: 36 psi
Key ON, Engine at idle: 32 psi
Key ON, Engine at 1500 RPM: 30 psi
The engine starts a little bit easier, but it still seems overly rich on start up: a little black smoke on start up which clears in a couple of seconds.
I haven't tried adjusting the MAF with the 5 mm allen wrench, but I have read the procedure from the Samba.
I want to be sure I've covered all the basics before I launch off on that path.
To all my vanagon friends: Thank you for your suggestions. I've acted on every one of your helpful insights. I'm making progress.
What next?
Kind regards,Mike M 

    On Friday, November 18, 2016 11:28 PM, David Beierl <dbeierl@ATTGLOBAL.NET> wrote:
 

 At 20:42 11/18/2016, OlRivrRat wrote:
>n 18 Nov , 2016, at 4:55 AM, David Beierl wrote:
>
> > even if engine vacuum changed 1:1
>
>        1:1 What ?

Even if engine vacuum was reduced by an inch of mercury for every inich of mercury decrease in ambient pressure.

Yrs,
d