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it's the dreaded PFFFE code! dun dun dun! (More help needed!)

24K views 26 replies 11 participants last post by  BadlandsRacer  
#1 · (Edited)
CEL on. AccessPort reads the code as PFFFE, with no description behind it. Subaru dealership's OBD-II diagnostics don't read any codes. Code returned after being cleared with AP. Ideas?
 
#2 · (Edited)
#5 ·
#12 ·
Re: it's the dreaded PFFFE code! dun dun dun!

well was born in Russia if it helps. Well about your car, does it drive normally, any smoke out of the exhaust or oil cap, rough idle, have you changed your sparkplugs since you bought the car? problem can be caused by bad sparkplug or coilpack or injector. The only way to find the problem yourself is if you find out which cylinder is misfiring to switch the injector or sparkplug with another cylinder(one at a time) and see if the other cylinder is misfiring. I haven't had this problem so im sure somone that has can give you better advice.
 
#13 ·
#14 ·
Re: it's the dreaded PFFFE code! dun dun dun!

yeah, thats not good. should have left her stock. You might as well start with trying to figure out if she is indeed misfiring, maybe check your coils, plug wires, if all seems well inspect your plugs for discoloration to find the problem cylinder. Your partial throttle problem is over my head, if i had to guess it would be a problem with the tune or a leak.
 
#15 ·
Re: it's the dreaded PFFFE code! dun dun dun!

A leak sounds more likely...since it was doing it both before and after the tune. God only knows where the leak would be though. Everything I've inspected looks solid.

Should have left her stock? Are you kidding?!
 
#20 · (Edited)
Re: it's the dreaded PFFFE code! dun dun dun!

I lied, the problem isn't solved. The spark plugs were replaced yesterday. One was damaged. All were replaced. CEL stayed off until about an hour ago today. PFFFE code again. Additional advice please?
 
#21 ·
Bump for more help!
 
#22 ·
Have you swapped the coilpack to a different cylinder yet? See if the misfire follows that coilpack. Same thing for injector. Otherwise, Compression/leakdown test next.
 
#23 ·
Compression/leakdown test was performed while we had everything pulled apart enough to get to the spark plugs. Came back A-OK. And the PFFFE code doesn't designate a cylinder...it's not even readable by dealer diagnostics...only AccessPort. There's no description by it. If it weren't for IWSTI, I wouldn't even know it was a misfire code.
 
#26 ·
Compression/leakdown test was performed while we had everything pulled apart enough to get to the spark plugs. Came back A-OK. And the PFFFE code doesn't designate a cylinder...it's not even readable by dealer diagnostics...only AccessPort. There's no description by it. If it weren't for IWSTI, I wouldn't even know it was a misfire code.
Man, I would try swapping injectors like JDM-STi said. Sorry can't be of more help. I thought you knew atleast what cylinder. Maybe worth a call or visit to a subie dealership and speaking to a tech. If they nail it down for you, buy the tech a case of beer or something. If they try and get you to do diagnostic check, screw it.
 
#24 ·
I had the same problem on our LGT. It ended up being a bad injector that had to be replaced under warranty. Make sure that your spark plugs are gapped correctly also.
 
owns 2019 Subaru WRX STI Base FP Green Flex Fuel
#25 ·
Dealership just did all new spark plugs, not too worried about those. Injectors wouldn't be covered under warranty, hope it's not that. Also, they're fairly new. It may be a coilpack, but I'm still open to other suggestions.