Another dwell question

[OG Velvet]

[busdaddy]

[OG Velvet]

[busdaddy]

[OG Velvet]

Should I try replacing the vacuum lines going there first?
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

Replaced vacuum hoses that connect to the plastic tee and the FPR and things changed a little. Now when I pull off the hose from the FPR the bus dies.
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[busdaddy]

Hmmm, odd that fixing a line would make things worse. The real test for a FPR is with a Mighty vac like hand vacuum pump, plug the line that went to it and draw a vacuum on the FPR while watching the gauge, the bus doesn't have to be running but the pump has to be running (depress the flap in the AFM, key on).
If the FPR is NFG then fixing the vacuum line could have stopped a vacuum leak that was leaning it enough at idle to compensate for the excess pressure (pressure is how L-jet richens the mixture).
_________________
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[OG Velvet]

Well I drove it to work this morning and something interesting is happening. No bucking at all but the RPMs are going up and down when there is no load on the engine.

I did replace the 3 vacuum hoses at the tee.

Before I replaced the hoses, when I removed the hose to the FPR there was very little sound. With the new lines, when I removed the hose, there was definitely a loud vacuum sound.
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

I also want to reiterate that the pressure gauge has never moved. It stayed solid on 30 psi no matter what I did.
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[Wildthings]

If it is not moving when you change the vacuum applied to the nipple then your FPR is not functioning properly.

[OG Velvet]

So the $million question is... could this have been causing my intermittent bucking/ hesitation issue all along?
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[SGKent]

yes - put only the vacuum tester hose on the nipple coming from the plenum. You should see the vacuum change a great deal as the engine speeds up and slows down. Then hook a two way tee up to the nipple with one branch going to the FPR and the other going to the gauge. Try again. The test should be identical to the first test above. If it changes the FPR is leaking vacuum. If it is the same as the first test, and now the FPR vacuum is going up and down, then your leak is somewhere else.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[OG Velvet]

**Update**

Idle is still fluctuating. The bucking is almost all gone. Though it did do it pretty hard a few times the other night. It takes about ten seconds of cranking to get it to start in the morning.

Just replaced the fuel lines and FPR.

No change.

Wit's.

End.
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

*Bump*

The idle is going up and down. More like dipping down from a regular idle. It has a hell of a time starting when cold.

Intermittent bucking is still present.

Voltage at coil 15 is 13.77- 13.87

When I remove the alternator belt, it drops to 11.67- 11.77

I still am running my old distributor. Sent the Bus Depot POS back (still waiting for refund...)

I did do one thing that got me running for a month or so. The idle has still been erratic, but the bucking stopped for awhile. I sprayed out the distributor with electronics cleaner. A bunch of rust colored cleaner ran out. (Not sure if it was really rust or old oil/ grease) Should I just bite the bullet and get my distro rebuilt?

Again. All new fuel lines, filter and FPR. Don't think it's fuel related.
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

Idle still sounds like this (skip about 30 seconds in)

[SGKent]

did you ever replace

fuel filter with proper fuel injection filter?
fuel pressure regulator?
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[OG Velvet]

Both filter (proper FI filter) and FPR are brand new.


Just checked again for vacuum leaks. Can't find any. S boot is good
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

*Update*

Just adjusted my AFM by turning it all the way in while running and then backing it out until it sounded good. As soon as I started turning it in it sounded way better. I now have my AFM backed out about 2 turns from all the way in. The idle issue is all but gone. Took it for a drive and it sounded great.

Holding breath for the hundredth time...

I guess only time will tell if the bucking comes back.

Are there any other adjustments I should make after messing with the AFM screw?
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[OG Velvet]

**Bump**

Back to the same old issues.

Has a VERY hard time starting. To the point that I need to put a charger on the battery because I'm cranking so long.

Once started, it warms up fine. Then the idle just starts "dipping" out. I have no other way to describe it. Idles around 1500 rpm and then it drops down to about 400 for 2 seconds or so and it goes back up. It almost sounds like it's been switched off and then it catches again.

Ideas?
_________________
'67 13 Window
'77 Westy
'69 Sunroof Beetle
'65 Honda Dream

[SGKent]

dump a teaspoon of gas in the plenum or S Boot when cold to see if it starts right up. If so test the Cold Start Valve and circuit. They get fragile with age so don't break it. They are getting to be made from unobtanium.

When was the last time you did a full tune-up, with oil change and set the AFM - run a smoke test for vacuum leaks?
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin