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Thanks to both of you for the tip. Was really a pretty easy job once I got into it. New injectors going in tomorrow. Thanks again.

Put the new injectors in this morning. Will drive it tomorrow and see if it still misses under load. Next step will be a new air flow meter.

whats wrong with your old one?

Put new injectors in Saturday. Drove it today. Still misses...........Running out of ideas. Next will probably be a new mass air flow sensor. Possibly a fuel injection resistor? M really stumped. Practically everything has been replaced. Money is not the object. Just want to solve the mystery so I can feel confident to drive it anywhere.

Ignition, wiring and grounds--- Check, clean and or redo all grounds first.
Replacing the push-on grounds with hot-glued waterproof heatshrink loops that bolt down under a nut/washer is a huge win.

Your wiring harness is 35 years old... If money is no object, buy a new one, the one I saw was much better quality than factory. Could save a LOT of headaches. OTOH the AFM and ignition bits are all 35 years old too...

(OK, I can't resist...)
OTOH, if you are really adventurous (and emissions laws allow it where you are) upgrade to a modern programmable EMS--- it might not cost THAT much more than just a new harness and a few factory EFI repair parts.

Crank trigger, LS2 coils, can use the injectors you just bought, the factory manifolds work great...(adding a TPS is trivial, BTDT, several times) gets rid of that troublesome HV distributor etc.

You don't even need to buy a trigger wheel*... I'm using the dust vent holes on the (engine side) of the flywheel (line up with the pressure plate bolts) and a modified distributor for sync. VW provided a large access hole that lines up perfectly.

*if using MS1 or MS2extra or MS3, not sure if any other aftermarket EMS supports 6/1 wheel setup.

Thanks. I will check all the grounds I can find. I think I will pull the petronix out and put points back in and try it too, but it missed before with the points. The dizzy is original. Maybe a new one is the way to go. Do not have enough knowledge to even attempt a new wiring harness. My electrical knowledge is very limited so I have been replacing things that might be causing the problem. Thanks again for the response.

New wiring harness is a plug and play type deal, very easy and very worth it.
http://kyleautomotivespecialties.com/products
I do believe this guy comes very highly reccomended. Also there also atleast used to be french aftermaket/replacment AFMs (air flow meters are what we call em on a bus) that might be worth it.

Thats my next best guess is the AFM. It missed before I put the petronix in and just ran points. Do not think it is the dizzy either as it starts immediately and throtle response in very quick. I would think if the dizzy was bad it would not rev up while sitting and hitting the gas. Would think the vac advance is ok. I am going to pull the valve covers and check for a possible broken vavle spring. Going to try and turn each spring. They should not turn at all. If one does that may be the problem. Just want to really find the cure. Thanks for the response.

The LJet AFM (and pretty much everything other than the ECU itself) can be thoroughly tested with only a DVM.

AFMs die ... What happens is the variable resistor track wears out over time/vibration in a few spots, and it leaves a dead spot in the sweep.

Gently move the vane and watch for glitches.
(cheap analog meter or display easiest to interpret for this, mine has a bar graph)

If it is bad I'd seriously consider a full system upgrade, as they haven't been made in 20+ years, cost serious $, and weren't dead reliable when new.

I agree with you. The AFM is my next step. I do see rebuilt ones on line from about $160 on up depending on who is selling it.
Fusername gave me a link on a wiring harness that is pretty much plug and play. I called and talked to Kyle. He charges $375 + a core charge for the old harness. He said he uses better wire etc. Turn around time is about 3 weeks if I order one. Still do not think it is the harness but I will probably replace it too when I solve the problem. Just woundering. Does anyone sell the computer that the 32 pin plug plugs into? I think it is fine. We we looked at the AFM you can see ware marks across the sweep.
I do not know how to use a DVM and do not own one. Wish I did....LOL My brother in law has one. Do not know where to connect it on AFM or what reading I would be looking for?

Most everyone tells me the computer is the most relaible thing of the whole setup, they really just don't fail. Granted I had one fail on me, but it was a all or nothing deal. just suddenly didn't work period.

Replace the AFM, the wiring harness just makes things super more reliable cause you have all new connectors.

Working on electrical problems without a meter is akin to working on electronics by sense of smell.

You can buy a perfectly usable DVM for <$20, but you get what you pay for.
Radio shack still sells the little analog meters cheap IIRC, they work as well, just loads the circuit a little.

but I do believe good enough for his uses? I actually bought one JUST for this purpose the other day, I have a nice DVM, but I wanted analog to look at the sweep. Getting ready to revamp a FI rig I have in a box. It worked, but the AFM was flaky. getting a home made harness if I can find those crimp connectors from somewhere other than germansupplyscott. pile, got a lead?

For this particular use the analog sweep works better.

I have an ancient Simpson 260 i use for such things.

They still make them, basically liftetime tools if treated with respect they deserve.
They are, however, NOT $20

You can probably pick up a good used one w/case for <$50.
Well worth the $.

They have made them since the 1930s, and they looks almost identical today.(externally)
They are NOT old junk, unless someone treated them like it.
You want a reasonably recent one for safety reasons if you are ever measuring line voltage etc.

Where do I find the engine code on my bus engine. When I look for AFM's they talk about ones for certain codes. Also the AFM on my bus has a Bosch number of 0 280 200 018. The local VW guy here has three out there that are used but the Bosch number ends 012 not 018. I wounder if it would work? I have no way to know what numbers fit what vehicle. Do you guys have any idea how to refrence these. I do not know of any place to check????? Remember my bus is a 76 2.0 Delux Campmobile. Will a 020 interchange with the 018? Talked to Walt at the Bus Boys today. He told me to brass wire brush all the connections and the put the dialectic grease on them. Pretty much done except I can not get the 32 pin plug to the ECU out. Got it loose at the bottom and I tilt it up but I am not sure how it releases at the top. Looks like a pin but I see no release. Need to get it loose so I can clean the pins.


http://www.thesamba.com/vw/forum/archiv ... 595--.html
Maybe you can make heads or tails of this.