Lean Idle/Misfire - P0335
Jun 17, 2019, 01:55 PM
#31
Newbie
Thread Starter
in my 8 sometimes the car leans or richens a bit when i let it idle, was told it does that to adjust fuel trims..
and i've seen the same in multiple evos as well.
you can also have a leak on the manifold gaskets, how much boost is it holding when u do the boost leak test?
and i've seen the same in multiple evos as well.
you can also have a leak on the manifold gaskets, how much boost is it holding when u do the boost leak test?
Jun 17, 2019, 09:10 PM
#32
I test up to 30psi or more. You would be surprise of what you find. Your car may not run that much pressure, but sometimes that's what it takes to finally hear some of the smaller/more difficult to find leaks.
To confirm no leaks, I make sure my pressure gauge drops about 1psi per second.
To confirm no leaks, I make sure my pressure gauge drops about 1psi per second.
Jun 18, 2019, 03:05 AM
#33
Evolving Member
i was boost leak testing about 15-20psi. I cleared up all of the boost leaks, i found like 8 of them. Engine holds the pressure really nicely now and i'm positive there aren't any more boost leaks. I know what you're talking about, but the way it idle's and afr's behave is not normal, i'll take a video of startup when i leave work and i'll post it so you can see exactly what i'm talking about.
+1
Jun 18, 2019, 07:58 AM
#34
Newbie
Thread Starter
I test up to 30psi or more. You would be surprise of what you find. Your car may not run that much pressure, but sometimes that's what it takes to finally hear some of the smaller/more difficult to find leaks.
To confirm no leaks, I make sure my pressure gauge drops about 1psi per second.
To confirm no leaks, I make sure my pressure gauge drops about 1psi per second.
It's blown off at 20psi before, pretty spooky! I'll hit it with some hairspray and give it a shot!
Jun 18, 2019, 10:46 AM
#35
Jun 18, 2019, 04:03 PM
#36
Newbie
Thread Starter
Technical difficulties - I finally got a video of cold startup. Sorry for the constant focusing noise. You can skip through the middle, most important is the beginning and the end, where I tap the gas once its warmed up and idle AFR's go back to normal.
Jun 24, 2019, 08:38 AM
#37
Newbie
Thread Starter
Got the right spark plug socket and pulled the plugs. Oil was seeping into a spark plug tunnel through one of the o ring gaskets for the valve cover (spark plug gasket?). Found that the valve cover bolts were all seemingly loose, snugged those up. Those gaskets should all be new since the rebuild, so I think the bolts had just vibrated a tad loose and was letting oil into one of the plugs. Decided to check the gap since I had them out - oil fouled plug was about ~.35 and the other 3 were ~.24.. I cleaned that one up w/ a wire brush and gapped back to ~.24. I also disconnected the battery while doing this to reset the ECU. Didn't fix my lean idling issue but I think I may have found where that misfire was coming from. Drive to work today seemed a lot more consistent w/ more throttle response/instant power, less jumpy and a smoother idle (idle was sounding like a lumpy aggressive cam before). Making progress!
Last edited by 9TechNine9; Jun 24, 2019 at 08:45 AM.
Jul 18, 2019, 07:04 PM
#38
Newbie
Thread Starter
Still trying to find the culprit. Finally got some datalogs, however there is no AFR to go off of in the log. Didn't know I needed the adapter to log that. I'm not sure if I selected the right values to datalog, someone let me know if I need to select something else and do another datalog. I took 2 data logs, one of a cold startup - 18+ AFR's the entire time, and then a datalog as described above where once its warmed up I tap the gas and it corrects itself to normal AFR's.
Jul 19, 2019, 11:57 AM
#39
Newbie
Thread Starter
Looking through the datalogs, only thing I see that is a little odd is in the CORRECTION datalog... No "02 Feedback" until I tap the gas. Could that be because its going from open loop to closed loop?
Jul 22, 2019, 07:18 AM
#40
Newbie
Thread Starter
Realized I could check CEL's through EvoScan. No CEL's present on gauge cluster but when I pulled them in EvoScan I got p0335 for a crankshaft position sensor. Cleared it, started it up again and it didn't come back. From my understanding, If the sensor was bad the car wouldnt turn on so I thought that was kind of weird.. Today on the way to work it started misfiring like crazy when coming to a stoplight, AFR's were jumping all over the place. On engine decel, there was a spike of ~12 AFR when usually its completely lean on decel.. on the highway I had random jumps of AFR from ~12-16. I'm going to replace that fouled plug and make sure there isn't oil leaking into that cylinder and go from there. Really hoping this hasn't turned into a serious issue and that I can fix it myself. Should probably run a compression and leakdown test at this point..
Jul 29, 2019, 07:19 AM
#41
Newbie
Thread Starter
Replaced the fouled plug. Compression test showed 160psi across all cylinders and a leakdown test showed about 3-4% each cylinder. No CEL on gauge cluster but code p0335 came back. Would definitely make sense if that was the issue, but I'm always hesitant to throw parts at a car. Going to have a friend come over to help confirm if this is the issue before I purchase the sensor - he has a tool which we can watch the signal from the sensor. This problem can be so intermittent, it makes it harder to diagnose. At least my Block/Head is ok!
Sep 9, 2019, 10:34 AM
#42
Newbie
Thread Starter
Replaced the Crankshaft Position Sensor yesterday, still getting lean idle/misfire. The worst part was messing with the power steering to get to the Crankshaft Position Sensors wiring that runs behind it. Probably took me about 5-6 hours with watching some of the football games. I was able to sneak the sensor behind the timing belt on removal and install, so no need to remove the timing belt for this job for what it's worth to anyone out there. Moving on to the Camshaft Position Sensor. From my understanding a p0335 CEL could also be caused by a bad Camshaft Position Sensor.
Sep 24, 2019, 07:30 AM
#43
Newbie
Thread Starter
Replaced the Camshaft Position Sensor last night. Terminal to negative on battery fell off when I disconnected the battery - must have been the culprit for occasional no crank no starts.. anyways I also cleaned up my grounds. Checked spark plugs again, all were gapped to .024 except for cylinder 1 which worked its way to a .026 gap this time. The actual plug looked a lot better this time around with not as much fouling. Seems I have fixed the slow oil seep into that cylinder that was coming from a spark plug tunnel gasket, the top of the piston in cylinder 1 was a lot cleaner but I still saw something wet on top of the piston - looked and smelled like fuel.
Still haven't fixed the issue.. This is driving me absolutely nuts at this point especially since I'm just throwing parts at it. Does anyone else have another suggestion??? Every time I go through the car like this it runs smoother and better but that misfire/lean idle is still there.
Still haven't fixed the issue.. This is driving me absolutely nuts at this point especially since I'm just throwing parts at it. Does anyone else have another suggestion??? Every time I go through the car like this it runs smoother and better but that misfire/lean idle is still there.
Sep 25, 2019, 06:00 PM
#45
Newbie
Thread Starter
Ok so I checked for codes in EvoScan for the first time since I replaced the Crankshaft & Camshaft Position Sensors and I didn't get any codes.. so no more p0335, but I'm still having the issue. This has got me seriously stumped but I'm sure its something simple. Can anyone take a look at my tune/datalogs? I would seriously appreciate it! From what I can tell in my datalogs, looks like the once I get the 02 feedback to turn on it starts dumping fuel to return to normal afr's.