77 Westy high rpm hesitation

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Amskeptic
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Re: 77 Westy high rpm hesitation

Post by Amskeptic » Fri May 24, 2019 7:57 pm

GreenWesty83 wrote:
Fri May 24, 2019 5:15 pm
vwlover77 wrote:
Thu May 23, 2019 9:35 am
You can also remove the TS-2 from the variables. After the engine is good and warm, just ground the wire. The TS-2 resistance drops to 0 when hot. Still having the problem? Then it’s not the TS-2 (although it could be the wiring to it).
So I’m going to ask the ignorant question. Mainly in the name of not damaging my bus. But how would I safely ground the sensor? Could I make a little inline jumper to plug it into a ground? Or unplug the sensor and plug in the wire to ground? Please advise!
We are wandering here ... what was the answer to the wiper track question?
Was there no white visible?

What was the mixture when cold then warm (wiper nudge test)?
Colin
BobD - 1978 Bus . . . . . . . . . . . 111,155 miles
Chloe - 1970 bus . . . . . . . . . . . 206,820 miles
Naranja - 1977 Westfalia . . . . . 108,000 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,885 miles

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vwlover77
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Re: 77 Westy high rpm hesitation

Post by vwlover77 » Sun May 26, 2019 7:47 am

GreenWesty83 wrote:
Fri May 24, 2019 5:15 pm
So I’m going to ask the ignorant question. Mainly in the name of not damaging my bus. But how would I safely ground the sensor? Could I make a little inline jumper to plug it into a ground? Or unplug the sensor and plug in the wire to ground? Please advise!
Either method could work. But I should also have stated: Get the engine good and warm, TURN IT OFF, then ground the TS2 wire. Restart and test drive.
Don

---------------------------
78 Westy
71 Super Beetle Convertible Autostick

"When we let our compassion go, we let go of whatever claim we have to the divine." - Bruce Springsteen

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Sun May 26, 2019 2:11 pm

Point of clarification. I have not yet performed the wiper nudge test yet. Chicken coup has taken priority! I was asking for clarification on the grounding of the TS 2 so I could preform all the tests on the same day, when I eventually have some garage time. Once I have completed the tests I will post my results. Sorry for the delays.

I have taken a better picture of the tracks however.
Attachments
IMG_1631.jpg
The red circle shows what appears to be white coming through. Green circle is flash reflection.
IMG_1631.jpg (382.48 KiB) Viewed 994 times
1977 Sage Westy
1968 Blue Bug

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vwlover77
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Re: 77 Westy high rpm hesitation

Post by vwlover77 » Tue May 28, 2019 8:26 am

The red circle is not anywhere near where the wiper would be during high rpm operation. If that is the only location with white showing, I would recommend cleaning the resistor track as suggested in Satchmo's earlier post. If that does not solve it, then proceed with the other tests.

Another thought: Have you verified that the spark plug ceramic insulators are clean and have no cracks?
Don

---------------------------
78 Westy
71 Super Beetle Convertible Autostick

"When we let our compassion go, we let go of whatever claim we have to the divine." - Bruce Springsteen

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Wed May 29, 2019 3:01 pm

I have not checked plugs. I will ad that to my list. As well as a general cleaning of the AFM. I shall obtain some contact cleaner as well.
1977 Sage Westy
1968 Blue Bug

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Amskeptic
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Re: 77 Westy high rpm hesitation

Post by Amskeptic » Sat Jun 01, 2019 5:57 pm

GreenWesty83 wrote:
Wed May 29, 2019 3:01 pm
I have not checked plugs. I will ad that to my list. As well as a general cleaning of the AFM. I shall obtain some contact cleaner as well.

Just a soft paper towel. You do not want to attack the carbon track.

Try to zero in on the misbehavior. Is it a fuel starvation soft loss or is it a hard-edged ignition cut out?
Colin
BobD - 1978 Bus . . . . . . . . . . . 111,155 miles
Chloe - 1970 bus . . . . . . . . . . . 206,820 miles
Naranja - 1977 Westfalia . . . . . 108,000 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,885 miles

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Tue Jun 04, 2019 12:13 pm

Amskeptic wrote:Try to zero in on the misbehavior. Is it a fuel starvation soft loss or is it a hard-edged ignition cut out?
Colin
So, admittedly I do not definitively know the difference between the two, but I would tend towards a soft loss. At that higher RPM range it cuts out at that high rev at the top of whatever gear I’m in, (usually 3rd or 4th). But will stop when I shift gears or take foot off the pedal and let RPMs drop. So like in 4th at around 60mph I get the bucking and it won’t go any higher. But if I let off the pedal and keep it around 50-55 I can get it home fine.
1977 Sage Westy
1968 Blue Bug

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Tue Jun 04, 2019 2:44 pm

Amskeptic wrote:
Sat Jun 01, 2019 5:57 pm
GreenWesty83 wrote:
Wed May 29, 2019 3:01 pm
I have not checked plugs. I will ad that to my list. As well as a general cleaning of the AFM. I shall obtain some contact cleaner as well.
Try to zero in on the misbehavior. Is it a fuel starvation soft loss or is it a hard-edged ignition cut out?
Colin
So, admittedly I do not definitively know the difference between the two, but I would tend towards a soft loss. At that higher RPM range it cuts out at that high rev at the top of whatever gear I’m in, (usually 3rd or 4th). But will stop when I shift gears or take foot off the pedal and let RPMs drop. So like in 4th at around 60mph I get the bucking and it won’t go any higher. But if I let off the pedal and keep it around 50-55 I can get it home fine.
1977 Sage Westy
1968 Blue Bug

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Amskeptic
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Re: 77 Westy high rpm hesitation

Post by Amskeptic » Sat Jun 08, 2019 7:02 pm

GreenWesty83 wrote:
Tue Jun 04, 2019 2:44 pm
Amskeptic wrote:
Sat Jun 01, 2019 5:57 pm
GreenWesty83 wrote:
Wed May 29, 2019 3:01 pm
I have not checked plugs. I will ad that to my list. As well as a general cleaning of the AFM. I shall obtain some contact cleaner as well.
Try to zero in on the misbehavior. Is it a fuel starvation soft loss or is it a hard-edged ignition cut out?
Colin
So, admittedly I do not definitively know the difference between the two, but I would tend towards a soft loss. At that higher RPM range it cuts out at that high rev at the top of whatever gear I’m in, (usually 3rd or 4th). But will stop when I shift gears or take foot off the pedal and let RPMs drop. So like in 4th at around 60mph I get the bucking and it won’t go any higher. But if I let off the pedal and keep it around 50-55 I can get it home fine.

I am not going back to review everything (time!), but have you replaced your fuel filter (no Hastings)?
Coli
BobD - 1978 Bus . . . . . . . . . . . 111,155 miles
Chloe - 1970 bus . . . . . . . . . . . 206,820 miles
Naranja - 1977 Westfalia . . . . . 108,000 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,885 miles

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Mon Jun 10, 2019 8:29 pm

I did replace fuel filter when I experienced the heaving cutting out initially. Which reminds me of a detail. It seems the hesitation or cutting out becomes worse going up steep inclines? Which did make me initially think fuel filter or tank debris? But then I figured if it was tank debris why would it run so well after sitting for a period of time?
1977 Sage Westy
1968 Blue Bug

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Re: 77 Westy high rpm hesitation

Post by Amskeptic » Tue Jun 11, 2019 5:31 pm

GreenWesty83 wrote:
Mon Jun 10, 2019 8:29 pm
I did replace fuel filter when I experienced the heaving cutting out initially. Which reminds me of a detail. It seems the hesitation or cutting out becomes worse going up steep inclines? Which did make me initially think fuel filter or tank debris? But then I figured if it was tank debris why would it run so well after sitting for a period of time?
Dispersal from the clog point. Then it sucks towards the filter anew and clogs anew. I do not think that is the issue. Do you have a fuel gauge?
Colin
BobD - 1978 Bus . . . . . . . . . . . 111,155 miles
Chloe - 1970 bus . . . . . . . . . . . 206,820 miles
Naranja - 1977 Westfalia . . . . . 108,000 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,885 miles

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Re: 77 Westy high rpm hesitation

Post by GreenWesty83 » Wed Jun 12, 2019 7:22 am

I have a fuel pressure gauge. For testing correct?
1977 Sage Westy
1968 Blue Bug

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asiab3
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Re: 77 Westy high rpm hesitation

Post by asiab3 » Wed Jun 12, 2019 10:26 am

Yep! Our own Randy in Maine posted a nice write up here:

https://www.itinerant-air-cooled.com/vi ... f=50&t=213

If the issue is intermittent, you may have to drive with the pressure gauge visable. Make SURE your setup is a guaranteed No-Leak hose and gauge, my FLAPS gauge is leaking from its compression fitting after just two years. :pale:

Don’t lose the tiny screw on the test port; you’re stranded without it and its washer.

Robbie
1969 bus, "Buddy."
119k miles with me.
296k miles on Earth.

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Re: 77 Westy high rpm hesitation

Post by EngineerMaxwell » Thu Jun 27, 2019 8:30 pm

This sounds an awful lot like a problem I had with my double relay connections. I found that the female spade connectors in the white plugs going to the double relay were recessed too far and intermittently lost contact at higher RPM's. Removed them from the plugs and slid them individually onto the DR terminals: my headache finally went away. It took me 8k miles, tracing circuits, checking continuity and isolation, and who knows how many hours (days) to determine root cause. I also had a soldered wire connection at a fuel injector resistor *barely* hanging on. I replaced all 4 resistors because everything was so brittle at the soldered terminations (insulation included).

I got to enjoy 65 miles of absolute bliss before I parked it because of a burnt exhaust valve (see another post for that issue).

Best,
Alex

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Amskeptic
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Re: 77 Westy high rpm hesitation

Post by Amskeptic » Fri Jun 28, 2019 6:53 am

EngineerMaxwell wrote:
Thu Jun 27, 2019 8:30 pm
I got to enjoy 65 miles of absolute bliss before I parked it because of a burnt exhaust valve (see another post for that issue).

Best,
Alex
Link us to your exhaust valve post ... condolences.
Next time try less "bliss". The Universe punishes such things.
Colin :blackeye:
BobD - 1978 Bus . . . . . . . . . . . 111,155 miles
Chloe - 1970 bus . . . . . . . . . . . 206,820 miles
Naranja - 1977 Westfalia . . . . . 108,000 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,885 miles

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