Itinerant Air-Cooled

I have a 1980 air cooled van with an automatic transmission. It uses a 039 906 021 C ECU. Where can I get this tested. Would someone be willing to plug it into their good running van to test it for me ? I would pay $30 for the test.

Where are you located? That will certainly affect responses here. :)

Robbie

flyfisher111 wrote: ↑

Fri Sep 13, 2019 5:43 am

I have a 1980 air cooled van with an automatic transmission. It uses a 039 906 021 C ECU. Where can I get this tested. Would someone be willing to plug it into their good running van to test it for me ? I would pay $30 for the test.

Let's not go there just yet.

What are your current symptoms?
Colin

I am in Pa. But would mail it anywhere. I am having trouble under load. Idles good put into drive and have to add gas or it wants to stall. My gas pedal feels like an on off button. The full throttle switch will not raise the idle at all. According it Bentley I should replace the ecu. I have check all the wires for continuity. If people sell rebuilt ecu s how do they know there're working without testing it? But I can't find anybody that tests them.

I have never personally witnessed a bad ECU. A) Does the engine rev correctly in neutral or park? If so, the ECU is likely fine.

B) Your throttle pedal FEELS like an on/off switch? Or the engine responds to smooth pedal movement like an on/off switch? Since it sounds like you have an automatic transmission, there could be several different causes for your listed symptoms.

The full throttle switch is only at play during full throttle. Ignore it for now; idle and part-throttle based running should be 100% fine with it out of the loop.

These issues could be something as simple as an idle speed set too low, ignition timing set incorrectly, a vacuum leak from one of the many hoses, or one of several other systems not set/adjusted correctly.

C) Where are you located? Consider putting a general area in your profile, Colin appears to have some flexibility this October for an appointment if you're near the South. :)

Robbie

I did discovered a problem with my distributor. I don't have a tach gauge so I always set the timing at 7.5 degrees. I found that reving engine only advanced the timing about 10/12 degrees max.j

The distributor I bought is one of those "electronic up-grades" which I converted back to points because the points work better. Unfortunately I sold my original on ebay for $20. Don't know if I should mess with this distributor or buy a rebuilt Bosch.

However, I still have questions about the ECU. I understand it's an easy target for engine woes, but the fact that the full throttle switch doesn't function make me question what else in there isn't working. These engines don't have a lot of horse power so you have fight for every pony you can find. Still would like to find out if the ecu adjusts for load on the engine. And is there anyone who tests these things? Seems to me that someone could make alot of money testing ecu s.

Thanks for your input folks.

flyfisher111 wrote: ↑

Sat Sep 14, 2019 5:25 am

Thanks for your input folks.

Based on your symptoms, I would look carefully at the AFM plug. Sometimes it is not fully seated or the little fingers get pushed back and you lose all variable inputs. Do you get a rapid change in running when you nudge the little wiper either way 1/8" at idle?

You have a goldmine of field-tested knowledge here in Robbie and me. Let's carefully narrow this down. It is annoying to wait for responses, but it is cheaper than taking it to a shop where they may or may not know the arcana.
Colin

I had my air flow meter serviced by Fuel Injection Corp.

AFAIK what you got was refurbished but not meticulously serviced. It will probably not be set up to suit your engine out if the box.

You say you don’t have a tach? A timing light with one built in is affordable. But you don’t need to know revs when timing to max advance, just watch the timing mark while revving the engine and when the mark stops moving you’ll know you’re at max mechanical advance (vacuum hose to distributor unplugged of course). Set it to 28 degrees and you’re done with timing.

The advance curve on whatever distributor you’re running probably will not accommodate 7.5 at idle as well as the more essential 28 at full mechanical advance. A rebuilt Bosch would be lovely but I’d hold on the purchase until you’ve finished troubleshooting..

I tweeked the wiper arm leaner about an 1/8 of an inch. The idle liked that. I have a timing light with a tach built in but unfortunately it craps out at about 2400 rpm. The distributor I cleaned and put in. I have a little m ore total advance aboutI 14 degrees. I took a good guess as to where 28 degrees would be. I picked up some power so I advanced it a little more. It picked up a little more power. But where do I stop. With the top advance set at 32 degrees my idle works out at about 15 degrees which makes it hard to start.

Stop at 28 degrees, no more. You have a timing scale?

Yes I do. I have a good temp gauge, Dakota its reading 350 being pushed hard on suburban streets. I don't hear any pinging.

Well I messed around all day cleaning and adjusting points, rotor, cap etc.. I tweaked the advance stops out a bit on my distributor. I adjusted the cog in my Air flow meter, 6 notches counter clockwise. It is running better now I can feel a range on my gas pedal, not the on / off feeling I had earlier. I don't think it's 100 percent yet but definitely a big improvement . I have a used 022 605 205S distributor coming next week. Where can you buy a rebuild kit for a Bosch distributor.

Thanks for help folks.

You have a goldmine of field-tested knowledge here in Robbie and me.

I agree with this statement.