P071, P074, P300 codes
11-20-2023, 10:48 PM
#1
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P071, P074, P300 codes
Hello all, this is my first time in a forum, I just bought a corvette c6 2008 ls3 and it is showing codes P071, 074 and P300, I already look for air leakages and replaced the MAF sensor but the codes still there and I am not even able to reset them with my scanner, is there anybody here that have had the same problems in the past?, I will appreciate any help, thanks.
11-26-2023, 02:50 PM
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St. Jude Donor '12
Corvette Tuner in Tampa
Assuming you mean PO171/PO174 codes, says your running lean. If those codes are true, the PO300 misfire code may be happening because you are running lean.
Try a smoke machine test. They are pretty easy to make if you look them up on YouTube.
If you have an aftermarket intake manifold, they may have pinched a gasket during the install. It would be a lot easier to use a smoke machine on it to see where the smoke leaks out from than chasing parts.
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Try a smoke machine test. They are pretty easy to make if you look them up on YouTube.
If you have an aftermarket intake manifold, they may have pinched a gasket during the install. It would be a lot easier to use a smoke machine on it to see where the smoke leaks out from than chasing parts.
EMAIL: Tuning@TampaTuning.com
Website >>> https://shop.tampatuning.com/
CHECK OUT MY SHORTS : https://www.youtube.com/@tampatuning/shorts
Street Performance Tune Package starting from $390.00
Instagram: TampaTuning
11-27-2023, 01:05 PM
#3
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Hello all, this is my first time in a forum, I just bought a corvette c6 2008 ls3 and it is showing codes P071, 074 and P300, I already look for air leakages and replaced the MAF sensor but the codes still there and I am not even able to reset them with my scanner, is there anybody here that have had the same problems in the past?, I will appreciate any help, thanks.
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Tampa Tuning (11-28-2023)
11-30-2023, 09:05 PM
#4
Le Mans Master
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St. Jude Donor '13-'14-'15
Lean codes can be created by a fouled MAF sensor due to an aftermarket oiled air filter---The MAF wires get oil soaked and burns onto the wires making the MAF read wrong
Check your LTFT fuel trims they should always read "0" or slightly negative Clean the MAF with brake clean and run it awhile ------then correct the LTFT fuel trims using the MAF table in your tune
A P0300 misfire code can be caused by many things An aftermarket cam can create "FALSE MISFIRES" due to the engine shaking from the cam at idle 1st determine if in fact there is a REAL misfire If not then its false and can be corrected again in the tune by deleting the misfire tables
Check your LTFT fuel trims they should always read "0" or slightly negative Clean the MAF with brake clean and run it awhile ------then correct the LTFT fuel trims using the MAF table in your tune
A P0300 misfire code can be caused by many things An aftermarket cam can create "FALSE MISFIRES" due to the engine shaking from the cam at idle 1st determine if in fact there is a REAL misfire If not then its false and can be corrected again in the tune by deleting the misfire tables