Hard cold start

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Fri Oct 23, 2015 6:52 pm

Latest post of the previous page:

VWinVT wrote:I do get knotted up....part of my charm!! :). The fuel pump contacts are separated when the ENGINE is off and the AFM is parked. For the 3 years I have owned this van, the fuel pump always came on when the key was in The ON position. I always thought it was supposed to do that, I now know better. While checking the cold start, AAR and the ThermoTime Switch, the pump suddenly stopped coming on when the key was in the ON position. The ENGINE continued to start and run as it always did, except I did not hear the pump come on with the key in the ON position.
Now the ENGINE will fire up and run for 3 seconds and die. Throttle has no effect. Is it possible that the fuel pump contact switch is faulty in the AFM?
Not likely, but please turn on ignition and move wiper manually. Pump should run. If it does, the contacts and connector on the AFM harness are fine. If pump refuses to run, remove the AFM connector and bridge 36 and 39 with a little jumper. Does this turn on fuel pump? If yes, look for any little fingers that may have been pushed back into the connector block. They should all be in a line and plug in to the AFM securely.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Fri Oct 23, 2015 7:30 pm

Amskeptic wrote:
VWinVT wrote:I do get knotted up....part of my charm!! :). The fuel pump contacts are separated when the ENGINE is off and the AFM is parked. For the 3 years I have owned this van, the fuel pump always came on when the key was in The ON position. I always thought it was supposed to do that, I now know better. While checking the cold start, AAR and the ThermoTime Switch, the pump suddenly stopped coming on when the key was in the ON position. The ENGINE continued to start and run as it always did, except I did not hear the pump come on with the key in the ON position.
Now the ENGINE will fire up and run for 3 seconds and die. Throttle has no effect. Is it possible that the fuel pump contact switch is faulty in the AFM?
Not likely, but please turn on ignition and move wiper manually. Pump should run. If it does, the contacts and connector on the AFM harness are fine. If pump refuses to run, remove the AFM connector and bridge 36 and 39 with a little jumper. Does this turn on fuel pump? If yes, look for any little fingers that may have been pushed back into the connector block. They should all be in a line and plug in to the AFM securely.
Colin
I did this check today...well first part as the wife and kids (3 and 1 1/2) came home. Anyway, key ON, turn wiper so fuel,pump contacts touch and nothing...no fuel pump. I will 'build a bridge' tomorrow...I hope that solves it....either way....it will be repaired.

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Sat Oct 24, 2015 9:39 am

VWinVT wrote:
key ON,
turn wiper pump contacts touch no fuel pump.
I will 'build a bridge' tomorrow...
Do you get a click at the double relay when you turn on the ignition?
Did you get a click at the double relay when you moved the wiper?
Make sure double relay is getting voltage from coil + when ignition is on.
Keep an eye on all grounds that you happen across. They must be secure.

The bridge is a small piece of wire stripped 1/4" at the ends. Just stick it in the terminals 36 and 39.
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

VWinVT
Getting Hooked!
Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Sat Oct 24, 2015 9:59 am

Amskeptic wrote:
VWinVT wrote:
key ON,
turn wiper pump contacts touch no fuel pump.
I will 'build a bridge' tomorrow...
Do you get a click at the double relay when you turn on the ignition?
Did you get a click at the double relay when you moved the wiper?
Make sure double relay is getting voltage from coil + when ignition is on.
Keep an eye on all grounds that you happen across. They must be secure.

The bridge is a small piece of wire stripped 1/4" at the ends. Just stick it in the terminals 36 and 39.

Thanks. I did not near hear, nor did I actively listen for, a click at the double relay in either situation...but I will.

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Sat Oct 24, 2015 5:04 pm

ITS ALIVE!!! :cheers: I think it just missed my wife...I had her sit in the seat and turn the key to ON... and CLICK goes the double relay. So, now I'm holding my breath....I move the wiper arm and nothing. So then divine inspiration struck and I moved the fuel pump contact lever to the left and BAM click. So I guess my 'ham handed adjustments' bent the fuel pump switch too far. Readjusted and the fired right up! i feel a bit silly that it was something so simple and something that I caused.... :blackeye:
My van has California emissions...so the O2 sensor fights every adjustment I make. Can I simply unplug the O2 so I can get this thing to run at respectable temperatures at highway speed? It is currently slightly lean at idle at higher rpm's, as it was designed to be.

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Sat Oct 24, 2015 7:18 pm

VWinVT wrote:ITS ALIVE!!! :cheers: I think it just missed my wife...I had her sit in the seat and turn the key to ON... and CLICK goes the double relay. So, now I'm holding my breath....I move the wiper arm and nothing. So then divine inspiration struck and I moved the fuel pump contact lever to the left and BAM click. So I guess my 'ham handed adjustments' bent the fuel pump switch too far. Readjusted and the fired right up! i feel a bit silly that it was something so simple and something that I caused.... :blackeye:
My van has California emissions...so the O2 sensor fights every adjustment I make. Can I simply unplug the O2 so I can get this thing to run at respectable temperatures at highway speed? It is currently slightly lean at idle at higher rpm's, as it was designed to be.

Lawdy lawdy . . . . .

Do you have a Bentley? It shows you how to defeat the closed loop so you can adjust baselines. Do you have idle stabilizer plugs over on the left side?
In the meantime, if you have an O2 sensor in the system, then yes, disconnect the plug before adjusting mixture, which you want to be slightly lean, only slightly lean. Trying driving it with the O2 sensor unplugged and let us know how it does.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

VWinVT
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Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Sat Oct 24, 2015 7:27 pm

I do have a Bently...I will look for this procedure tomorrow. Yes, I do have an idle stabilizer on the left side of engine bay. Ok....I wil D/C the O2, adjust and report back.

VWinVT
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Location: Northeast Kingdom Vermont
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Re: Hard cold start

Post by VWinVT » Sun Oct 25, 2015 5:44 am

I am still a bit confused/thinking something still isn't quite right. With the key ON and when I touch together the AFM fuel pump contacts ; I hear a click at the double relay (separate from the click I hear at the relay when the key turns to ON). Should I be hearing the fuel pump run at this point?

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Sun Oct 25, 2015 8:59 am

VWinVT wrote:I am still a bit confused/thinking something still isn't quite right. With the key ON and when I touch together the AFM fuel pump contacts ; I hear a click at the double relay (separate from the click I hear at the relay when the key turns to ON). Should I be hearing the fuel pump run at this point?
Yes. The AFM contact click is sending 12 volts down to the fuel pump. Grasp the fuel rail and see if you can feel the subtle vibration of fuel flow/pump activity. Sometimes, these pumps are actually quiet.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

VWinVT
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Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Sun Oct 25, 2015 9:42 am

:thumbleft: I unplugged the O2, taped off the sensor end. I have the AFM set so that I am getting no engine response in either direction. Fuel pump contacts adjusted properly.

This motor has NEVER run this well!!! :sunny: I got to 30 mph before I even knew what happened. The motor runs quieter too!
The air temperature today is 52*. We have 25mph winds today...the windmills are screaming...And so was I! With the tail wind I drove 60mph with CHT of 350*. Driving back into the wind I held 50-55 (except going up the hills) with a max CHT of 375*. I know those temps will go up some when fully loaded in the summer heat.

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Amskeptic
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Re: Hard cold start

Post by Amskeptic » Sun Oct 25, 2015 10:30 am

VWinVT wrote::thumbleft: I unplugged the O2, taped off the sensor end. I have the AFM set so that I am getting no engine response in either direction. Fuel pump contacts adjusted properly.

This (engine) has NEVER run this well!!! :sunny: I got to 30 mph before I even knew what happened. The (engine) runs quieter too!
The air temperature today is 52*. We have 25mph winds today...the windmills are screaming...And so was I! With the tail wind I drove 60mph with CHT of 350*. Driving back into the wind I held 50-55 (except going up the hills) with a max CHT of 375*. I know those temps will go up some when fully loaded in the summer heat.
Step. Away. From. The. Vehicle.
Keep your hands where I can see them.
Now drive.
Colin :blackeye:
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 94,615 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,990 miles

VWinVT
Getting Hooked!
Location: Northeast Kingdom Vermont
Status: Offline

Re: Hard cold start

Post by VWinVT » Sun Oct 25, 2015 11:08 am

:salute: Will do!
Thank you for your help. I appreciate it.
If you r ever in northern VT, u r more than welcome to stop in. :sunny:

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