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Discussion Starter · #21 ·
The DOD cam has a different profile on the lobes that shut down due to the difference in lifters. If the lifters they put in were not DOD lifters (and why would you when doing the delete?) then you have 4 cylinders getting more valve lift than the others.

Is it enough to matter. I don't know lol.
i feel like at this point it has to be the only reason. so many of the cars symptoms didnt exist before the dod delete kit was done. what else could make it random misfire at this point? any ideas what it could be?
 

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Discussion Starter · #22 ·
The difference between afm and non-afm lobes is 2 or 3 thousands of an inch due to the slightly looser preload on the afm lobes. Plenty over the years have done DOD delete on the stock cam and it make no difference. GM probably did it to keep valve train quiet. On the flip side, RCR DOD cams use the same lift and duration on all lobes.
so you dont think switching to a non dod cam will make the misfire stop?
 

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The misfire if it is cam related, it’s because a lobe is wiped out. Not because it is using all standard lifters. Did the shop ever show you the “squealing “ lifter?
 

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Discussion Starter · #24 ·
The misfire if it is cam related, it’s because a lobe is wiped out. Not because it is using all standard lifters. Did the shop ever show you the “squealing “ lifter?
no they just told me that the cam didnt look like it had any damage.
 

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So you didn't have a misfire before you started and now you think the cam after they changed just lifters? hmm. Did at least the squeal go away? Regarding switching to a non dod cam to make the misfire stop - Maybe, but I'm kind of doubting...First I'd check whetever typical cause is for that misfire code. Maybe another issue.
 

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Having the misfire code would be good to know
 

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Again suggest taking the vehicle back to the initial performance shop. Wouldn't spend over $1,800 on a d.o.d. delete, have subsequent issues and turn to a forum for troubleshooting advice. The onus lies with the shop to remedy the issue(s) and further evaluate the situation. Take or tow the car back as soon as possible or else you're doing the over $1800 spent and yourself a disservice. The very last thing you want to do is bailout an entity perchance performing questionable or shoddy work. If they refuse to fix the car, then resort to other legal methods such as contacting the better business bureau, credit card company, leaving applicable Yelp, Google, etc. reviews. Either way, wouldn't let them off the hook and interested to read what they have to say.
 
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Discussion Starter · #29 ·
Again suggest taking the vehicle back to the initial performance shop. Wouldn't spend over $1,800 on a d.o.d. delete, have subsequent issues and turn to a forum for troubleshooting advice. The onus lies with the shop to remedy the issue(s) and further evaluate the situation. Take or tow the car back as soon as possible or else you're doing the over $1800 spent and yourself a disservice. The very last thing you want to do is bailout an entity perchance performing questionable or shoddy work. If they refuse to fix the car, then resort to other legal methods such as contacting the better business bureau, credit card company, leaving applicable Yelp, Google, etc. reviews. Either way, wouldn't let them off the hook and interested to read what they have to say.
im working with the shop still. it nearby my job so i havent lost contact with them. we are still trying to figure it out. we ordered a non delete cam & are going to get that done next week. fingers crossed it fixes the problem. thank you for your feedback brother.
 

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Discussion Starter · #30 ·
So you didn't have a misfire before you started and now you think the cam after they changed just lifters? hmm. Did at least the squeal go away? Regarding switching to a non dod cam to make the misfire stop - Maybe, but I'm kind of doubting...First I'd check whetever typical cause is for that misfire code. Maybe another issue.
it was more like birds chirping in my hood noise. & yes the only changed lifters. got the misfire code took it back & they changed spark plugs but still having the misfire
 

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Ok that’s multiple cylinders misfire. Could be a vacuum leak or bad plugs or wires or a dirty or clogged injectors. I would also want to know if you have full fuel pressure. Bottom line is the shop handed you back a poor running car. They should , at their cost, diagnose the cause of the misfire. I still feel there is wear on the cam. It may not be causing the misfire, it will limit the performance. Each chirp it made was a shaving of metal that came off the cam lobe/lifter wheel. Did the remove the oil pan to clean it out and the oil pump pick up?
 

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i feel like at this point it has to be the only reason. so many of the cars symptoms didnt exist before the dod delete kit was done. what else could make it random misfire at this point? any ideas what it could be?
Can you match the cylinder misfires to the cylinders that had the DOD lifters on them? Might confirm your theory
 

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P0300 doesn’t identify any one cylinder as a misfiring. Lifter failure is also not exclusive to the afm lifters. Squealing is a sign of the lifter turning in the worn lifter tray. Ask the shop if the wear was on the regular or afm lifter?
184694
 

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I saw this post and was astounded. Having been around these cars since they first arrived here, I cannot believe that there is a shop that would not replace the cam after the dreaded "chirp". Their statement that the cam didn't "appear" to be damaged is lame. It's another 1-2 hours to replace it. And, exactly how well can you examine it in the engine? I call BS. They expected you to come back. Personally, I'd write those hacks off and find a real engine shop. These things are really easy to fix and give at least another 100k of increased performance if they know what they are doing. I'd get a new shop and an oil analysis.
 

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Discussion Starter · #35 ·
I saw this post and was astounded. Having been around these cars since they first arrived here, I cannot believe that there is a shop that would not replace the cam after the dreaded "chirp". Their statement that the cam didn't "appear" to be damaged is lame. It's another 1-2 hours to replace it. And, exactly how well can you examine it in the engine? I call BS. They expected you to come back. Personally, I'd write those hacks off and find a real engine shop. These things are really easy to fix and give at least another 100k of increased performance if they know what they are doing. I'd get a new shop and an oil analysis.
im right there with you man. trying to work with them so my money is not a waste. but im close to finding a new shop!
 

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Take it to Vengeance Racing to figure it out!
 

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Listed a few actions in post number twenty-seven. Seriously, get the ball rolling as soon as possible. Document everything and retain all paperwork. Hopefully, you didn't pay them in cash. The next shop should have prior experience performing the work desired on the vehicle.
 
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