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Syncing cams to crank

flbchbm

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#41
I just read your other post:
May 24, 2020
"Since this thread is older than mine I'm going to bump. Getting the same code as well. So far I've changed: crankcase vent valve, valve cover which includes pcv valve, checked all vacuum lines and made sure both catch cans were closed, cleaned throttle body, reinspected and reinstalled intake gasket for both manifold and aux fuel, bought a brand new manifold as a known good, rechecked throttle body gasket and realigned, recalibrated throttle body, replace MAF sensor, checked for leaks in all charge pipes, tightened all bungs including tmap sensor, installed new o ring in map tap for better seal, bought new oil dipstick, checked for exhaust leaks, resealed exhaust anyways. I cannot find where this p2282 is.... The only other options I have are 1 tune isn't measuring air properly or 2 an intake valve is messed up. I would otherwise ignore it but it's causing an excessively high number of misfires at high rpm. With a tech in the car with a diagnostic tool in mode 6 we saw 500 misfires on both cyl 2 and 3 in 10 seconds at 4000 rpm held."

I don't know if I missed other posts relating to your situation, so pardon me if I ask questions already asked... Did you check that 2015 evap harness? Since you have a Mountune engine, you can't tune it back to stock tuning for testing, can you? What is your plug gap?

I'm sure you've already read:
https://www.obd-codes.com/p2282
Causes for this code may include:
Large vacuum leak on or near the intake manifold
Defective MAP or MAF sensor
Bad intake manifold gasket
PCM or programming error

And read this:
http://www.stratifiedauto.com/blog/misfires-and-the-ecoboost-when-should-you-worry/

and this:
https://www.motor.com/magazine-summary/diagnosing-ford-misfires

and finally:
if you have a misfire that you cannot fix by replacing ignition coils and spark plugs, this is a common problem on some Fords. They will develop a misfire on 1 or more cylinders and you may not even get a CEL. The misfire is sometimes caused by a burnt ignition driver in the ECU.
 


Last edited:
OP
R

Rocketst

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Thread Starter #42
The car misfires between 4-16 times when light throttle is reintroduced after letting off. Areas above 4k rpm of sustained throttle produce rapid and constant misfiring. At wide open throttle or under acceleration there are usually no misfires.

Sent from my moto z4 using Tapatalk
 


OP
R

Rocketst

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Thread Starter #43
I just read your other post:
May 24, 2020
"Since this thread is older than mine I'm going to bump. Getting the same code as well. So far I've changed: crankcase vent valve, valve cover which includes pcv valve, checked all vacuum lines and made sure both catch cans were closed, cleaned throttle body, reinspected and reinstalled intake gasket for both manifold and aux fuel, bought a brand new manifold as a known good, rechecked throttle body gasket and realigned, recalibrated throttle body, replace MAF sensor, checked for leaks in all charge pipes, tightened all bungs including tmap sensor, installed new o ring in map tap for better seal, bought new oil dipstick, checked for exhaust leaks, resealed exhaust anyways. I cannot find where this p2282 is.... The only other options I have are 1 tune isn't measuring air properly or 2 an intake valve is messed up. I would otherwise ignore it but it's causing an excessively high number of misfires at high rpm. With a tech in the car with a diagnostic tool in mode 6 we saw 500 misfires on both cyl 2 and 3 in 10 seconds at 4000 rpm held."

I don't know if I missed other posts relating to your situation, so pardon me if I ask questions already asked... Did you check that 2015 evap harness? Since you have a Mountune engine, you can't tune it back to stock tuning for testing, can you? What is your plug gap?

I'm sure you've already read:
https://www.obd-codes.com/p2282
Causes for this code may include:
Large vacuum leak on or near the intake manifold
Defective MAP or MAF sensor
Bad intake manifold gasket
PCM or programming error

And read this:
http://www.stratifiedauto.com/blog/misfires-and-the-ecoboost-when-should-you-worry/

and this:
https://www.motor.com/magazine-summary/diagnosing-ford-misfires

and finally:
if you have a misfire that you cannot fix by replacing ignition coils and spark plugs, this is a common problem on some Fords. They will develop a misfire on 1 or more cylinders and you may not even get a CEL. The misfire is sometimes caused by a burnt ignition driver in the ECU.
Wow... This is a ton of info... Thank you.. um give me about a day to get back to you on this one lol.

Sent from my moto z4 using Tapatalk
 


MagnetiseST

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#44
Wow... This is a ton of info... Thank you.. um give me about a day to get back to you on this one lol.

Sent from my moto z4 using Tapatalk

Definitely check the ignition drivers in the PCM. You said it tested good, but you never know.


definitely check your evap harness, the check valves can go bad and lead to other issues down the road.
 


OP
R

Rocketst

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Thread Starter #46
I just read your other post:
May 24, 2020
"Since this thread is older than mine I'm going to bump. Getting the same code as well. So far I've changed: crankcase vent valve, valve cover which includes pcv valve, checked all vacuum lines and made sure both catch cans were closed, cleaned throttle body, reinspected and reinstalled intake gasket for both manifold and aux fuel, bought a brand new manifold as a known good, rechecked throttle body gasket and realigned, recalibrated throttle body, replace MAF sensor, checked for leaks in all charge pipes, tightened all bungs including tmap sensor, installed new o ring in map tap for better seal, bought new oil dipstick, checked for exhaust leaks, resealed exhaust anyways. I cannot find where this p2282 is.... The only other options I have are 1 tune isn't measuring air properly or 2 an intake valve is messed up. I would otherwise ignore it but it's causing an excessively high number of misfires at high rpm. With a tech in the car with a diagnostic tool in mode 6 we saw 500 misfires on both cyl 2 and 3 in 10 seconds at 4000 rpm held."

I don't know if I missed other posts relating to your situation, so pardon me if I ask questions already asked... Did you check that 2015 evap harness? Since you have a Mountune engine, you can't tune it back to stock tuning for testing, can you? What is your plug gap?

I'm sure you've already read:
https://www.obd-codes.com/p2282
Causes for this code may include:
Large vacuum leak on or near the intake manifold
Defective MAP or MAF sensor
Bad intake manifold gasket
PCM or programming error

And read this:
http://www.stratifiedauto.com/blog/misfires-and-the-ecoboost-when-should-you-worry/

and this:
https://www.motor.com/magazine-summary/diagnosing-ford-misfires

and finally:
if you have a misfire that you cannot fix by replacing ignition coils and spark plugs, this is a common problem on some Fords. They will develop a misfire on 1 or more cylinders and you may not even get a CEL. The misfire is sometimes caused by a burnt ignition driver in the ECU.
I will be double checking myself for my own sanity the status of the wiring going to my ignition coils. That video was really cool, how he was able to use a simple test light to explain how the pcm gives spark to the plugs. I figure if I can test that it'll help me determine if I need to test the pcm itself. I just don't know how. My spark plugs are currently gapped at .015. I know it's a bit tight but I kept tightening the gap due to the carbon build up on them in hopes it'd help with the misfires and I've done so many other things maybe it has maybe it hasn't but it doesn't foul at all anymore. All 4 plugs stay generally very clean. I've had them gapped this way for almost 300 miles now. As far as the evap harness goes, it was a brand new harness which came with a brand new check valve, I confirmed this with Ron since I didn't install it.

Sent from my moto z4 using Tapatalk
 


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#47
I would suggest looking at and comparing the spark plugs. If the center plugs are black and oily you could have ring issues on the center cylinders. If so an increase oil in the combustion chambers could be the cause of your misfires. If it is then looking for knock events in this area could confirm that. Because an oil/fuel mix in a gasoline engine can cause increase the tendency for detonation. BTW, in many 4 cylinder engines the center cylinders tend to wear out or fail first. Because they typically run hotter than the end cylinders.
 


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Location
Tucson
#48
Not an engine diagnostic guy, but hopefully can add a cent or two? Being everything between the throttle body and head are checked and good (with your eyes on it), that only leaves the intake manifold itself and the PCV (which was replaced).

Edit: Firstly, I'd double check all hoses hot and cold side of the intercooler. Also check the intercooler for leaks (pressure/vacuum test it). Somehow, the compressor on the turbo could be pulling air from outside too. Just remember P2282 indicates an air (or vacuum leak) between the throttle body and the valves and could be a small leak not easy seen.

I'm assuming you went with aftermarket cams - first guess would be cams themselves. The PCM is calibrated for stock cams and a specific amount of metered air. More duration or lift demanding more air in a different pattern than stock could set the code. Only a guess, and I have no idea if the airflow ratios are modified when tuning. Edit: also zero degreeing the cams to the crank could help too. Don't know how on an OHC engine, but old school V8s are easy for a reference.

Second, valve bucket lash/clearance, which should be noticeable during a leakdown at least. Per workshop manual: acceptable clearance between cam and bucket intake is 0.010–0.014 in (0.255–0.345 mm) and exhaust is 0.014–0.018 in (0.355–0.445 mm).

Third, sticking valve, bad/burnt valve, or bad valve seat.

Fourth, per workshop manual, they want to verify proper operation of the PCV system.

Fifth, head or cam could be warped.

Sixth, VVT phasers both mechanical and electrical. Super common these days on the 3.5 and 2.7, but could be an issue here.

Last of the last, PCM. Not common, but shit happens. We've also seen issues with tunes causing things to not work (like the a/c), so if possible (without blowing a rod or bending a valve) try a tune back to stock.

Also check wiring for any damage. Damaged connectors specifically for the PCV. Any damaged intake bits. Smoke the intake system if you can, a very helpful test if you can source the tools or shop for it. I hope you can find it, whatever it ends up being! Things get very tedious and annoying when going aftermarket. Just keep it simple and diag from easy to hard. Another thing you can do is spray some brake cleaner (the flammable type) around all the intake bits to check for vacuum leaks. Best of luck!
 


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