Ok background story. I picked this motor up used in trade for some work and put it on my mako 238. I had rough idle, shaking at 1100 rpms and could never get make rpms/High rpms.
Here is what I've done
New
Vst filter
Inline filter
Water separator
Low fuel pressure pumps
New fuel regulator had low fuel pressure and old failed 35 psi test on air compressor
Cleaned all fuel injectors and filters
Link and sync with tps adjustment
Clean o2 sensor recently just replaced with ntk actually gained some rpm
New plug caps
Checked resistance on coils show good
New 17p prop instead of 19p gained 400 rpms
Ok with that said I have reached 4800-4900 with the new prop before it was 4400. After the new caps and o2 sensor it didn't change except at high rpms it would "engage"surge and I saw 5100 very quickly never held it was like that spark was trying to kick in. I came home and checked plugs and one cylinder being cylinder 3 had a very clean spark plug looks like it burned a little when surging but that's it. Was wet with fuel. I'm lost at this point I have low rough idle, popping some on muffs,shaking at 1100, not reaching fuel rpms, surging, and a very clean spark plug that has spark when grounded at idle on muffs, but that's not accurate enough to say it's strong enough right?. I would say I've narrowed it down to stator,pulser, or ecu. I don't have dva adapter to check stator but would it more likely be the pulser or any other tests I could do to narrow it down. Also compression even on all cylinders.
Thanks
Here is what I've done
New
Vst filter
Inline filter
Water separator
Low fuel pressure pumps
New fuel regulator had low fuel pressure and old failed 35 psi test on air compressor
Cleaned all fuel injectors and filters
Link and sync with tps adjustment
Clean o2 sensor recently just replaced with ntk actually gained some rpm
New plug caps
Checked resistance on coils show good
New 17p prop instead of 19p gained 400 rpms
Ok with that said I have reached 4800-4900 with the new prop before it was 4400. After the new caps and o2 sensor it didn't change except at high rpms it would "engage"surge and I saw 5100 very quickly never held it was like that spark was trying to kick in. I came home and checked plugs and one cylinder being cylinder 3 had a very clean spark plug looks like it burned a little when surging but that's it. Was wet with fuel. I'm lost at this point I have low rough idle, popping some on muffs,shaking at 1100, not reaching fuel rpms, surging, and a very clean spark plug that has spark when grounded at idle on muffs, but that's not accurate enough to say it's strong enough right?. I would say I've narrowed it down to stator,pulser, or ecu. I don't have dva adapter to check stator but would it more likely be the pulser or any other tests I could do to narrow it down. Also compression even on all cylinders.
Thanks
