71 Type 3 f.i. loping

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whc03grady
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71 Type 3 f.i. loping

Post by whc03grady » Fri Feb 04, 2011 12:56 pm

I'm starting to feel bad for hogging so much time/advice here, yet still having issues.

When in gear the car "lopes", for lack of a better term. With even pedal pressure, the rpms die off dramatically, but come right back up, and again, and again, and again, very regular-like. It's not as severe without a load.

MPS has been switched out, to no avail. I've got the TVS apart now, and am worried that that was a mistake.

Any thoughts?
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Amskeptic
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Re: 71 Type 3 f.i. loping

Post by Amskeptic » Fri Feb 04, 2011 9:41 pm

whc03grady wrote:I'm starting to feel bad for hogging so much time/advice here, yet still having issues.

When in gear the car "lopes", for lack of a better term. With even pedal pressure, the rpms die off dramatically, but come right back up, and again, and again, and again, very regular-like. It's not as severe without a load.

MPS has been switched out, to no avail. I've got the TVS apart now, and am worried that that was a mistake.

Any thoughts?
With D-Jet FI, loping is often rich running, which is what this system does with vacuum leaks. Vacuum leaks can crop up at any instant, injector o-rings if yours or not new, intake manifold gaskets, vacuum hoses splitting length-wise at the nipple, etc.
Sorry to hear you are having issues. I miss my little Squareback.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Fri Feb 04, 2011 11:41 pm

Amskeptic wrote:vacuum leaks
How are they detected if they're not obvious? Carb cleaner?
The injector rings are not yet two years old (June 2009).

Also, wouldn't a vacuum leak cause a bad idling condition as well? Everything's pretty smooth when the car's just sitting there. I probably misled when I said, "It's not as severe without a load"; I don't think it's there at all without a load. The idle is a little nomadic (wandering between 850-900 rpms) in neutral, but it doesn't act the same, if you catch my drift. It doesn't fall off a cliff, recover, fall off a cliff, recover, ad nauseum like it does when it's being driven.

I should do a video.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Re: 71 Type 3 f.i. loping

Post by Amskeptic » Sat Feb 05, 2011 10:01 am

whc03grady wrote:wouldn't a vacuum leak cause a bad idling condition as well?
Not with D-Jet, especially when cold. Engines like more fuel when idling and cold, and a D-Jet leak will make the engine happy . . . until it is fully warm and the richness finally chokes it.

Your engine is leaving factory parameters for some reason under acceleration. The ECU is going into caniptions trying to follow the sensors and throttle switch and MAP sensor around. Do you have a vacuum gauge?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Sat Feb 05, 2011 4:15 pm

Amskeptic wrote:Do you have a vacuum gauge?
I do now:

http://www.youtube.com/watch?v=iAMUpq9KF3c

According to the manual that came with the gauge, this condition indicates that the carburetor (or, presumably, f.i.) needs adjustment.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Sat Feb 05, 2011 8:23 pm

So all the spark plugs've been replaced. My fuel pressure gauge only goes up to 15psi, but it pegged it pretty quick. Point gap gapped within spec, timed, though that was difficult because I adjusted the idle in order to do the timing properly, and now the idle won't sit still. I'm going backward here.

Thinking fond thoughts of our 1995 Subaru,
whc03grady.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Re: 71 Type 3 f.i. loping

Post by Amskeptic » Mon Feb 07, 2011 6:27 pm

whc03grady wrote:
Amskeptic wrote:Do you have a vacuum gauge?
I do now:

http://www.youtube.com/watch?v=iAMUpq9KF3c

According to the manual that came with the gauge, this condition indicates that the carburetor (or, presumably, f.i.) needs adjustment.
You cannot swap the MAP sensor vacuum supply for your vacuum gauge take off. Your engine went to full-throttle rich the second that the MAP lost its vacuum. You can tee to that connection.
That is like unplugging the AFM in the bus.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Tue Mar 15, 2011 7:45 am

Amskeptic wrote:You can tee to that connection.
Okay, round two, line teed:
http://www.youtube.com/watch?v=TKRbd8v__0U
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Amskeptic
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Re: 71 Type 3 f.i. loping

Post by Amskeptic » Tue Mar 15, 2011 12:26 pm

whc03grady wrote:
Amskeptic wrote:You can tee to that connection.
Okay, round two, line teed:
http://www.youtube.com/watch?v=TKRbd8v__0U
Please give us a written report as well. I couldn't read the gauge through this pixelated medium, the idle sounded pretty good through my headphones, but what is the current state of running with gauge numbers? Was I correct that the gauge did very little movement from the "0" area? Might you have some dreadful vacuum leak that you cannot track down, like at the auxiliary air regulator/hoses?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Bleyseng
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Re: 71 Type 3 f.i. loping

Post by Bleyseng » Wed Mar 16, 2011 3:30 am

At idle you had about 12-13 in of vac, right? A little low but usually loping at idle is a vac leak somewhere!
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Wed Mar 16, 2011 10:41 am

Bleyseng wrote:At idle you had about 12-13 in of vac, right? A little low but usually loping at idle is a vac leak somewhere!
Ah, but it doesn't lope at idle--it idles just fine. In fact, I can't seem to replicate the problem in the garage; what you see in the video is not indicative at all of what happens when the car is in gear, moving (that is, trying to move) down the road.

I'll post again with the details Colin was asking for.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Re: 71 Type 3 f.i. loping

Post by whc03grady » Sat Mar 19, 2011 10:15 am

Amskeptic wrote:Please give us a written report as well. I couldn't read the gauge through this pixelated medium, the idle sounded pretty good through my headphones, but what is the current state of running with gauge numbers? Was I correct that the gauge did very little movement from the "0" area? Might you have some dreadful vacuum leak that you cannot track down, like at the auxiliary air regulator/hoses?
Colin
The needle spends most of its time around 13-14 with journeys into the upper teens when I rev it up.
Like I said, the loping only really happens under load; I can't get it to do it in the garage.
This one is in focus:
http://www.youtube.com/watch?v=Uyc16r9I5bo

Here's the car going down the road (best I could do):
http://www.youtube.com/watch?v=QuwC6V6Ol5g

Is a stuck valve a possibility?
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Amskeptic
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Re: 71 Type 3 f.i. loping

Post by Amskeptic » Sat Mar 19, 2011 4:15 pm

whc03grady wrote:
Amskeptic wrote:Please give us a written report as well. I couldn't read the gauge through this pixelated medium, the idle sounded pretty good through my headphones, but what is the current state of running with gauge numbers? Was I correct that the gauge did very little movement from the "0" area? Might you have some dreadful vacuum leak that you cannot track down, like at the auxiliary air regulator/hoses?
Colin
The needle spends most of its time around 13-14 with journeys into the upper teens when I rev it up.
Like I said, the loping only really happens under load; I can't get it to do it in the garage.
This one is in focus:
http://www.youtube.com/watch?v=Uyc16r9I5bo

Here's the car going down the road (best I could do):
http://www.youtube.com/watch?v=QuwC6V6Ol5g

Is a stuck valve a possibility?
If it idles OK, then a stuck valve is not an issue.
The engine is leaving ECU fuel map. Do we have known compatability between the ECU # and the manifold sensor #? Does your ECU have a mixture adjusting screw on its case?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Bleyseng
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Re: 71 Type 3 f.i. loping

Post by Bleyseng » Mon Mar 21, 2011 3:06 am

Looks more like a electrical spark issue with missing as it won't fire under load. Leaning out as you rev up usually is a missing thats constant.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

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whc03grady
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Re: 71 Type 3 f.i. loping

Post by whc03grady » Mon Mar 21, 2011 6:40 am

The MPS and ECU are both Es. In any case, they'd been a perfectly competent team for thousands of miles when this issue suddenly arose. I will look at the brain for a screw, but I don't remember seeing one last time I looked at it.

I should say that it doesn't feel like missing to me. What it feels like, exactly, is running out of gas. But the car doesn't die, it just dies off (and comes back), if you catch my meaning. The spark plugs have all been replaced.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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