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Discussion Starter · #21 ·
Yup, that's my thought but probably something I should do long-term anyways.
I also am going to grab a can of MAF cleaner and try to get everything clean, as well as spray it around everything I touched during the cam install process to see if I have an air leak somewhere. Based on the condition of the coil connectors and the trays that hold the engine wire harness I wouldn't be shocked if something is brittle/cracked and leaking.
 

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Discussion Starter · #22 ·
Got the valve shim tool but still waiting on the shims to get here, so no update there. I did get the P0430 code again, so I'm going to get a Karl Long O2 sim and some headers. I was thinking about getting the OBX short runner and adding in a pair of high flow cats so my car doesn't stink and is still fairly environmentally friendly since I don't need max HP and still drive it regularly.
I sprayed starting fluid around everything along the intake path that I touched during the cam install and couldn't find any leaks, so still no solution on what is causing my misfire at low rpm. I am going to move the cam gear to -2 and see if anything changes.
 

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Discussion Starter · #23 ·
Haven’t had a chance to do the valve shims yet, just been driving around to see if the code was gonna even come back. It took about 400 miles, but sure enough the TRAC OFF light started flashing and I confirmed it’s a Cyl 1 misfire code again. I got a freeze frame of the data when the code was tripped, and it looks like the ECU is running super lean at idle, any idea why? I’ve never seen it below -9% when I’ve checked in the past.
 

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Discussion Starter · #25 ·
Any way to test injectors without pulling the rail? I know before I put a finger on it and could feel inj 1 pulsing but stopped there.
I replaced both post-cat O2s last year, but I’ll see if I can test them with my OBD scanner.
 

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From memory isn't it the pre cats that check fuel trims, the post cat only checks that the cats are working?
 

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Discussion Starter · #27 ·
From memory isn't it the pre cats that check fuel trims, the post cat only checks that the cats are working?
Yep, good call. I’ll see if I can run a check on the pre-cat O2s too.
 

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Discussion Starter · #29 ·
Well based on my scanner the primary O2 sensors are ok.
At this point I’m leaning towards just getting an ECU and a tune to get everything dialed instead of working around the factory ECU. I’ve gotten some feedback on a couple IS Facebook pages and it sounds like I’m not the only one having this issue.
Panic wire has a PnP Link G4X setup that I am thinking about getting, which I believe is the replacement for the discontinued xcessive kit. I’ve already contacted a tuner near me who has experience with Link ECU, though I do have some hesitations about going standalone on a car that’s meant to be primarily street driven from a reliability standpoint. Not sure how justified they are, I just don’t have experience with standalone ECUs.
 

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Discussion Starter · #30 ·
Maybe a dumb question, but would running copper NGKs be causing issues? Saw some threads where the Denso plugs were hailed as king and got me thinking.
 

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Maybe a dumb question, but would running copper NGKs be causing issues? Saw some threads where the Denso plugs were hailed as king and got me thinking.
No, as long as they are gaped right and not fouled. On your scanner. Does it do live readings? If so check the responce rate. If they are slow to respond. It can cause an issue.
 

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Discussion Starter · #32 ·
No, as long as they are gaped right and not fouled. On your scanner. Does it do live readings? If so check the responce rate. If they are slow to respond. It can cause an issue.
It does do live readings, let me check that. When I pulled plug 1 a while ago it didn’t look fouled at all.
 

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Discussion Starter · #33 ·
Couldn't find injector response rate (assuming that's what you were referring to) or anything related to ignition besides advance at cyl 1 on the live readings for my scanner unfortunately. All I could get it ST/LT fuel trims, fuel system state (CL/OL), O2 voltages, and engine temps.
 

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Couldn't find injector response rate (assuming that's what you were referring to) or anything related to ignition besides advance at cyl 1 on the live readings for my scanner unfortunately. All I could get it ST/LT fuel trims, fuel system state (CL/OL), O2 voltages, and engine temps.
The response is for the primary O2 sensors.
 

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Discussion Starter · #35 ·
Went on a long road trip for spring break, and the car did great. Got a few hundred miles at a time without any CEL, but it's come back again with random misfire. I ordered a Link ECU from Panic and will be installing/tuning later this month. At this point I have just given up on using the cams with a stock ECU, but want to make sure everything else is OK before my dyno date.
I just had the thought, any chance replacing the vvti gear o-ring could be my issue? If it got put together just off from the factory balance, would this cause my random misfire that seems to only occur at idle? Timing marks still line up, so I don't think it's skipped a tooth or anything.
Also, for those with 264s and no CEL, what's the car like starting off idle? Seems like I need to give it a good bit of throttle to keep it from bucking. Can't remember what it was like before cams at this point though.
 

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Went on a long road trip for spring break, and the car did great. Got a few hundred miles at a time without any CEL, but it's come back again with random misfire. I ordered a Link ECU from Panic and will be installing/tuning later this month. At this point I have just given up on using the cams with a stock ECU, but want to make sure everything else is OK before my dyno date.
I just had the thought, any chance replacing the vvti gear o-ring could be my issue? If it got put together just off from the factory balance, would this cause my random misfire that seems to only occur at idle? Timing marks still line up, so I don't think it's skipped a tooth or anything.
Also, for those with 264s and no CEL, what's the car like starting off idle? Seems like I need to give it a good bit of throttle to keep it from bucking. Can't remember what it was like before cams at this point though.
Never bucked or did anything like you are experiencing. Smooth and quick on the ones I did.
 

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misfire (coil, wire, or ignitor)? I have seen them at idle only, apparently fine when the engine is spinning at speed. Engine or trans mount? Could rock around more than it should, wonder if that would bump it enough to trigger a sensor.
 

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Discussion Starter · #38 ·
If there is a misfire, it's definitely at idle only. New plugs, wires, and coil connectors, coils checked out ok. No clue on ignitor, though it was fine before the cam/timing belt install. I assumed the ECU was trying to lean out the idle mixture to reduce emissions, but with the cams it was going too far.
Definitely could be engine mounts, based on the age of the car and condition of the other rubber components (bushings, gaskets, etc.). Trans mount is fine from what I remember when doing the swap.
Does the damper that connected to the tensioner on manual cars actually make any difference? I never bothered to find/install one when doing the manual swap.
Solar, did your cars lope at idle with the 264's? I notice it loping and can feel some shaking when it gets to a low idle (<700 rpm).
 

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If there is a misfire, it's definitely at idle only. New plugs, wires, and coil connectors, coils checked out ok. No clue on ignitor, though it was fine before the cam/timing belt install. I assumed the ECU was trying to lean out the idle mixture to reduce emissions, but with the cams it was going too far.
Definitely could be engine mounts, based on the age of the car and condition of the other rubber components (bushings, gaskets, etc.). Trans mount is fine from what I remember when doing the swap.
Does the damper that connected to the tensioner on manual cars actually make any difference? I never bothered to find/install one when doing the manual swap.
Solar, did your cars lope at idle with the 264's? I notice it loping and can feel some shaking when it gets to a low idle (<700 rpm).
Not really lobe. You could hear it, but no real shake.
 

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Discussion Starter · #40 ·
Hm, so maybe my motor mounts are toast then. Wouldn’t be surprised, but I doubt that would cause a misfire code.
I’m also going to weld a bung on to the stock headers for my AEM wideband so I can get an idea of how lean it actually is at idle. Figured I might as well since the rear cat is on the way out anyways.
 
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