Hello everyone,
Thanks for reading my first post! I'm trying to chase down a gremlin of an issue and I'm running low on ideas. Any help?
Symptoms:
- rough idle, especially when cold (can sometimes hear small pops under the hood, yikes),
- needs a little extra finesse pulling away from a stop, especially when cold,
- cylinder 3 roughness with ocassional cylinder 3 knock,
- AF Learning 1 is generally 15-20 unless on throttle and then it's 0,
- smells like gas,
- will otherwise drive normally below 11 or 12 psi, although I have been running 20 psi for years with no issues.
- If I repeatedly floor it (for science), I can eventually get it to throw misfire codes, almost always for cylinder 3, sometimes 1, and sometimes all of them.
- gas mileage is kind of all over the place; sometimes normal, sometimes low, sometimes higher than ever.
Here is what has happened in the order it happened (note my entire car build is below):
- took my car in for an exhaust job, which should have been simple, but they crossthreaded my downpipe to turbo nut and handed me the keys. They also looked pretty guilty when I picked it up so who knows what they did...This may be unrelated, and I may also be paranoid because I have caught several places joyriding but fwiw...
- After that job, I removed the K&N intake, verrrrry lightly oiled it, and let it dry overnight. Then I reinstalled it, along with the intercooler, downpipe, and exhaust. Car suddenly pulled power under WOT, but otherwise drove normally with no codes.
- While investigating, my throwout bearing started making noise. I had started looking for exhaust leaks, but a local shop fixed the clutch in exchange for all of my money and said they would finish reinstalling the exhaust for me (more on that in a sec).
- I uninstalled, reinstalled, and checked the intake, intercooler, and intake manifold hoses a million times. It miiiight be that last hose (which is a pain), but it's on there tight with upgraded clamps.
- Then I checked the exhaust. I guess they didn't tighten up the rest of the exhaust after all...gaskets look OK, but it wasn't aligned, and it wasn't torqued to factory spec.
- I cleaned the MAF, which sort of made a slight change? Maybe a difference from a big drop of power to a kind of sputtering, both only under WOT?
- I broke down (me this time) and took it to Subaru, tail between legs. I don't know if it made me feel better or worse that they didn't know what was up either. He thought it might be plugs, but I did those about 2 years and 15k ago. I have never done coil packs. But why would those go out now, when it was fine before I started monkeying with the rest of this stuff? At least he asked for $275 in exhange for no solid answer, and offered to do plugs and packs for $1100 and a valve job for $5k. My car and I politely limped home.
- Then I replaced the rear O2.
- I don't know a lot about vacuum lines, but I checked what I could see. I know the blowoff to manifold hose is notorious, which I checked several times.
- I poured in a few ounces of Lucas fuel addititve, which I have never done in this car; but what the hey.
Thoughts:
- seems like a boost or vacuum, leak, right?
- seems like it's running lean/thinks it's running lean, and it's adding a lot of gas?
- the K&N intakes are controversial. I'm heard the stories about the oil fouling the MAF and I've heard that's a myth. I already went down that path. Maybe go back to stock? It would require me to shell out dough for a new custom tune...
- maybe invest in a smoke machine?
THANKS FOR ANY SUGGESTIONS, SUBARU BROS, BRUHS, and BRAS!
Here is my list of mods:
2013 WRX Sedan
K&N Intake
Process West Verticooler
Invidia dual-bung downpipe
Invidia Q300 catted exhaust
CSF Racing Radiator
Cobb APv3
Torqued Performance e-tune
Cobb adjustable short shifter
RCE SS1 Coilovers
Whiteline front and rear adjustable swaybars
Kartboy endlinks
Powerstop/Stoptech brakes
Thanks for reading my first post! I'm trying to chase down a gremlin of an issue and I'm running low on ideas. Any help?
Symptoms:
- rough idle, especially when cold (can sometimes hear small pops under the hood, yikes),
- needs a little extra finesse pulling away from a stop, especially when cold,
- cylinder 3 roughness with ocassional cylinder 3 knock,
- AF Learning 1 is generally 15-20 unless on throttle and then it's 0,
- smells like gas,
- will otherwise drive normally below 11 or 12 psi, although I have been running 20 psi for years with no issues.
- If I repeatedly floor it (for science), I can eventually get it to throw misfire codes, almost always for cylinder 3, sometimes 1, and sometimes all of them.
- gas mileage is kind of all over the place; sometimes normal, sometimes low, sometimes higher than ever.
Here is what has happened in the order it happened (note my entire car build is below):
- took my car in for an exhaust job, which should have been simple, but they crossthreaded my downpipe to turbo nut and handed me the keys. They also looked pretty guilty when I picked it up so who knows what they did...This may be unrelated, and I may also be paranoid because I have caught several places joyriding but fwiw...
- After that job, I removed the K&N intake, verrrrry lightly oiled it, and let it dry overnight. Then I reinstalled it, along with the intercooler, downpipe, and exhaust. Car suddenly pulled power under WOT, but otherwise drove normally with no codes.
- While investigating, my throwout bearing started making noise. I had started looking for exhaust leaks, but a local shop fixed the clutch in exchange for all of my money and said they would finish reinstalling the exhaust for me (more on that in a sec).
- I uninstalled, reinstalled, and checked the intake, intercooler, and intake manifold hoses a million times. It miiiight be that last hose (which is a pain), but it's on there tight with upgraded clamps.
- Then I checked the exhaust. I guess they didn't tighten up the rest of the exhaust after all...gaskets look OK, but it wasn't aligned, and it wasn't torqued to factory spec.
- I cleaned the MAF, which sort of made a slight change? Maybe a difference from a big drop of power to a kind of sputtering, both only under WOT?
- I broke down (me this time) and took it to Subaru, tail between legs. I don't know if it made me feel better or worse that they didn't know what was up either. He thought it might be plugs, but I did those about 2 years and 15k ago. I have never done coil packs. But why would those go out now, when it was fine before I started monkeying with the rest of this stuff? At least he asked for $275 in exhange for no solid answer, and offered to do plugs and packs for $1100 and a valve job for $5k. My car and I politely limped home.
- Then I replaced the rear O2.
- I don't know a lot about vacuum lines, but I checked what I could see. I know the blowoff to manifold hose is notorious, which I checked several times.
- I poured in a few ounces of Lucas fuel addititve, which I have never done in this car; but what the hey.
Thoughts:
- seems like a boost or vacuum, leak, right?
- seems like it's running lean/thinks it's running lean, and it's adding a lot of gas?
- the K&N intakes are controversial. I'm heard the stories about the oil fouling the MAF and I've heard that's a myth. I already went down that path. Maybe go back to stock? It would require me to shell out dough for a new custom tune...
- maybe invest in a smoke machine?
THANKS FOR ANY SUGGESTIONS, SUBARU BROS, BRUHS, and BRAS!
Here is my list of mods:
2013 WRX Sedan
K&N Intake
Process West Verticooler
Invidia dual-bung downpipe
Invidia Q300 catted exhaust
CSF Racing Radiator
Cobb APv3
Torqued Performance e-tune
Cobb adjustable short shifter
RCE SS1 Coilovers
Whiteline front and rear adjustable swaybars
Kartboy endlinks
Powerstop/Stoptech brakes
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