Have you emptied the tank and put some fresh fuel in? It may be more than a coincidence that this started happening right after he got gas.
Subaru FB25 - misfires and O2 sensor?
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I haven't, wasn't sure if that was a waste of time.
I did notice last night I seem to be getting a helIuva lotta condensation out of the tailpipes (fakey dual exhaust) when idling. Maybe lots of water in fuel?
All grounds look great and measured no more than a couple ohms but just the same I disassembled all I could find and cleaned, as well as batt terminals.
I've swapped all coils from left to right. I put two new inexpensive Autolite iridiums in #1 and #3 yesterday. If anything it got worse but honestly that could just be the nature of the problem as it's not consistent. It later seemed to return to its "regular" bad behavior.
Compression on both 1 and 3 is 100 after what sounds like four compression cycles and 110 after six.
I figure I'll run a leakdown on at least the right bank while I've still got those plugs out.
I've visually inspected for rodent damage but can't find anything resembling a chewed wire.
@Trav I did use my 505 on the coils. Looking at burn and ramp in digital or graph is.....inconclusive. It simply could be that my eye isn't detecting problem(s). I'd have to post vids of those for anyone to make sense of them.
Now in "chart" Burn Time was kinda interesting but it doesn't make any sense. The one outlier here was #2 but I again suspect it's just a red herring.
#1, which has sometimes shown misfire counts and once set a pending misfire code
#3 which seems to be THE problem child
#2, which has never shown any misfire counts
#4, which once had seven misfire counts (I'd lean toward counting this as statistically insignificant)
Engine was up to temp and I did find the probe is VERY sensitive to where on the coil it's positioned. I decided to use the back of the coil just in front of the electrical plug because that's where I'd see the greatest readings.
Now in "chart" Burn Time was kinda interesting but it doesn't make any sense. The one outlier here was #2 but I again suspect it's just a red herring.
#1, which has sometimes shown misfire counts and once set a pending misfire code
#3 which seems to be THE problem child
#2, which has never shown any misfire counts
#4, which once had seven misfire counts (I'd lean toward counting this as statistically insignificant)
Engine was up to temp and I did find the probe is VERY sensitive to where on the coil it's positioned. I decided to use the back of the coil just in front of the electrical plug because that's where I'd see the greatest readings.
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Also if this was "bad gas" would you expect to see wild fuel trims? Once up to temp I'm still seeing short term at 0 to 0.8 and long term at 9.4 (which feels a bit high)
And in the land of more extreme, has anyone ever seen the FB25 (with chain) jump time?
And in the land of more extreme, has anyone ever seen the FB25 (with chain) jump time?
#2 is on the drivers side front correct? Can you put it on digital and get the numbers instead of waveform?
You could use a in the rail fuel injector cleaning setup pressurized to 40 psi and use gasoline instead of the cleaner. Something like this will do, IIRC there is no Schrader on this one so you will go into the line connection on the left side of the manifold after removing the fuel pump fuse.
https://www.amazon.com/dp/B0CGN1QCP...p_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWxfdGhlbWF0aWM
You could use a in the rail fuel injector cleaning setup pressurized to 40 psi and use gasoline instead of the cleaner. Something like this will do, IIRC there is no Schrader on this one so you will go into the line connection on the left side of the manifold after removing the fuel pump fuse.
https://www.amazon.com/dp/B0CGN1QCP...p_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWxfdGhlbWF0aWM
CONCLUSION: bad gas! I should have entertained this possibility sooner, although the owner is.....interesting. I didn't fully trust his story coupled with the fact I use the same station A LOT and would have filled within days of him on either end.
It ran great on my Lang top end cleaner bootied onto the supply line.
Next question: is there a good way to trigger the fuel pump absent a tach signal? I don't see a fp relay but sure would be nice to make the pump do the heavy lifting. The fuse is always hot (like my wife as someone else would say)
It ran great on my Lang top end cleaner bootied onto the supply line.
Next question: is there a good way to trigger the fuel pump absent a tach signal? I don't see a fp relay but sure would be nice to make the pump do the heavy lifting. The fuse is always hot (like my wife as someone else would say)
Yeah it seems like their default "panic" response is to throw #1 and #3 misfires!
Fortunately this one was solved as bad gas
