Getting rid of skip pulses for fuel only setups

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msoultan
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Getting rid of skip pulses for fuel only setups

Post by msoultan »

So, this is starting to become more annoying than it was before as it makes for weird starts. Sometimes there's an initial "catch", so I stop cranking, but it was really residual fuel and the injectors still hadn't started firing yet because they were skipping... grrrr... Right now I have a distributor and unfortunately I don't have the time to switch over to a timing wheel as it's a very involved process on my engine. Plus, my distributor setup actually works quite nicely, so I don't know if I really want to start messing with it, especially while I'm trying to work on so many other fuel issues (ego, ve, etc, etc)

Would it be possible to investigate creating an option to allow the user to select "fuel only" or "fuel and spark"? And only if they select "fuel and spark" will the skip pulses option show up.

If the MS2 authors would be so kind to work on this fix (2.5 maybe?), I would really appreciate it. Otherwise, would anyone else be interested in helping me out with this? Not everyone using the MSII chip is doing spark and they shouldn't suffer poor starts because of that...

Thanks!
Mike
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Post by jsmcortina »

Even with fuel-only you still need to skip some pulses to accurately calculate rpm. However, on an initial start I'd agree that the code should be able to go into cranking mode and start shoving some fuel in there.

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msoultan
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Post by msoultan »

Yeah, I thought cranking mode just shot fuel in there for every pulse it received? Or is that how the MSI worked?
msoultan
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Post by msoultan »

I should probably qualify that with "every distributor pulse it received"...
UnaClocker
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Post by UnaClocker »

More priming pulse? Get enough fuel in there for it to run long enough to get past those skipped pulses?
Brian
'84 Dodge Rampage
msoultan
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Post by msoultan »

I had thought about that.. but I really don't like the priming pulse. I have a habit of turning my ignition on and off quite a few times when testing stuff, and the last thing I want to do is dump a bunch of fuel in the engine during that time...
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