New Diagnostic Software for MBE ECU

New Diagnostic Software for MBE ECU

Author
Discussion

crimpdoc

69 posts

197 months

Thursday 23rd September
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PetrolHeadPete said:
Iirc the balance springs can go soft but think that just lets the end most butterfly hold open too far which is not what you are seeing (if I read this right)

Everything else is absolutely locked in place by flats on shafts etc etc. So how on earth can it be over rotated at idle. Plus your air flow is Bob on. Mind you the rotational difference between 15% and 20% is not much. I assume if you plug in the loose / spare pot without bolting it on, it shows a very low %?
Looks like it is to do with the mechanical baseline position, but like you said the idle and position of all the actual butterflys are set spot on, can only presume its down to wear on the spindles

PetrolHeadPete

676 posts

159 months

Thursday 23rd September
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crimpdoc said:
Looks like it is to do with the mechanical baseline position, but like you said the idle and position of all the actual butterflys are set spot on, can only presume its down to wear on the spindles
That's just too weird! Wear wouldn't (can't) cause a rotational offset. And it would have have to be really worn to make it sloppy enough to get the error you're seeing. Just for sanity's sake, if you pop a feeler gauge past the "open" edge of the butterfly, you should not be able to get more than about 2 thou through there (iirc) (sorry, that's in inches too...still think in inches for feeler gauges!). Its really chuff all in terms of opening. I only ask to get a reference point for the overall set up.

crimpdoc

69 posts

197 months

Thursday 23rd September
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Nope i really cant figure it out, the throttle is just about closed 1 and 1/2 to 2 thou feeler gauge, sorted it now by opening the holes out slightly on the pot, maybe the later pots are different to the originals, I seem to remember that the original i had to change was spring loaded to the closed position

PetrolHeadPete

676 posts

159 months

Friday 24th September
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crimpdoc said:
Nope i really cant figure it out, the throttle is just about closed 1 and 1/2 to 2 thou feeler gauge, sorted it now by opening the holes out slightly on the pot, maybe the later pots are different to the originals, I seem to remember that the original i had to change was spring loaded to the closed position
I think you've done the only thing you can. Its also interesting that the old pot only just made it into the "ok" band. The new ones must be slightly different. I think Joolz has found something similar too, the new pattern parts are not quite the same as the OEM ford ones.

I converted mine to run single pot a few years back, and the remaining one is now centrally mounted between bodies 3 and 4 with an offset adjuster just in case. But it was a lot of faffing to get it right