unknown misfire

[EpsilonMSP3]

when i shift from 3rd to 4th it misfires, when im giving it around 80 ish % throttle it begins to misfire slightly, and ive replaced the coilpacks, spark plugs, and before you ask (if you ask) i dont know the brand of the spark plugs, or coilpacks. i replaced them a while ago to fix the problem and now its back. also i dont know the gap of spark plugs, i will be figuring all of this out tomorrow.

[Vansquish]

OK. Please list all of your modifications. Be specific (i.e. don't just say "aftermarket intake," tell us the specific intake and the internal diameter of the MAF housing). In addition, please tell us if there are any codes stored in the ECU.

[MSMS3]

Follow Vansquish’s advice and give us a full, detailed list of mods and fault codes.

What was the problem that led to replacing coil packs and plugs? Yes, it will help to know if the replacement parts were not OEM. If not OEM, the brand and part number may be important.

Gap those plugs down to .026”. They need to be iridium fine wire, either NGK or Denso, in the proper heat range for your mods. If mostly stock mods on stock or mild tune, stick with stock heat range.

[EpsilonMSP3]

Originally Posted by Vansquish OK. Please list all of your modifications. Be specific (i.e. don't just say "aftermarket intake," tell us the specific intake and the internal diameter of the MAF housing). In addition, please tell us if there are any codes stored in the ECU.

the only mods on the car are a cobb air intake, which is the one with the blue piping

Originally Posted by MSMS3 Follow Vansquish’s advice and give us a full, detailed list of mods and fault codes. What was the problem that led to replacing coil packs and plugs? Yes, it will help to know if the replacement parts were not OEM. If not OEM, the brand and part number may be important. Gap those plugs down to .026”. They need to be iridium fine wire, either NGK or Denso, in the proper heat range for your mods. If mostly stock mods on stock or mild tune, stick with stock heat range.

all codes were deleted after the spark plugs and coil packs were replaced because i thought the problem had stopped which for the most part it had, but now it is creeping back

[Vansquish]

Originally Posted by EpsilonMSP3 the only mods on the car are a cobb air intake, which is the one with the blue piping all codes were deleted after the spark plugs and coil packs were replaced because i thought the problem had stopped which for the most part it had, but now it is creeping back

Have you pulled the codes again? If you're suffering a misfire, the ECU is pretty quick at identifying that and will often generate codes within a few seconds.

Do you remember what the codes were?

[EpsilonMSP3]

Originally Posted by Vansquish Have you pulled the codes again? If you're suffering a misfire, the ECU is pretty quick at identifying that and will often generate codes within a few seconds. Do you remember what the codes were?

i dont remember the code number, but the description it gave was just unknown misfire, and no it hasnt thrown them again, because the last time it did the car was stuttering and dying as i was driving it, then the engine light came on and i fixed it or so i thought. now its coming back, but only a little bit, im sorry im not helping but this is all i have to work on because i was daft back when i first got it, now im gonna start writing things down for sure

Originally Posted by Vansquish Have you pulled the codes again? If you're suffering a misfire, the ECU is pretty quick at identifying that and will often generate codes within a few seconds. Do you remember what the codes were?

oh and it was only one code for the misfire.

[MSMS3]

Originally Posted by EpsilonMSP3 i dont remember the code number, but the description it gave was just unknown misfire, and no it hasnt thrown them again, because the last time it did the car was stuttering and dying as i was driving it, then the engine light came on and i fixed it or so i thought. now its coming back, but only a little bit, im sorry im not helping but this is all i have to work on because i was daft back when i first got it, now im gonna start writing things down for sure oh and it was only one code for the misfire.

Just get it scanned again, write down the codes, and report them here.

Back to the last parts you installed, coil packs and plugs. I really want to know the source and part numbers.

[EpsilonMSP3]

Originally Posted by MSMS3 Just get it scanned again, write down the codes, and report them here. Back to the last parts you installed, coil packs and plugs. I really want to know the source and part numbers.

i might actually go do that now

[EpsilonMSP3]

here is the coil packs i used

[EpsilonMSP3]

Originally Posted by MSMS3 Just get it scanned again, write down the codes, and report them here. Back to the last parts you installed, coil packs and plugs. I really want to know the source and part numbers.

done, i posted what i installed and couldnt get another code pulled along with the unknown spark plugs, so rn this is all i have to go on

[EpsilonMSP3]

Originally Posted by Vansquish Have you pulled the codes again? If you're suffering a misfire, the ECU is pretty quick at identifying that and will often generate codes within a few seconds. Do you remember what the codes were?

done, i found what i could

[MSMS3]

Now, we need you to get a rescan from the OBD2 port. If you don’t have a scanner, most auto parts stores will do a scan for free. Write down every number the scanner reports and post here. There are often “soft codes” that don’t trigger a check engine light, but show up on a scan.

You might want to pull one spark plug and take a photo of the writing on the side and check gap. I want to verify you installed the right plugs and that they are gapped down at or very near .026”.

What is the condition of your intake filter? Does it need cleaning or replacement? Have you cleaned the MAF sensor? All these are basic things to check if it’s not throwing a check engine light - yet.

[EpsilonMSP3]

Originally Posted by MSMS3 Now, we need you to get a rescan from the OBD2 port. If you don’t have a scanner, most auto parts stores will do a scan for free. Write down every number the scanner reports and post here. There are often “soft codes” that don’t trigger a check engine light, but show up on a scan. You might want to pull one spark plug and take a photo of the writing on the side and check gap. I want to verify you installed the right plugs and that they are gapped down at or very near .026”. What is the condition of your intake filter? Does it need cleaning or replacement? Have you cleaned the MAF sensor? All these are basic things to check if it’s not throwing a check engine light - yet.

okay so i just ran and got it checked, no codes, next, i cant take the plugs out myself because i dont have the right tools. and i have looked at the air filter and it is clean, now i havnet checked the maf which i will do tomorrow, good idea. i will try to keep yall updated

[MSMS3]

Originally Posted by EpsilonMSP3 okay so i just ran and got it checked, no codes, next, i cant take the plugs out myself because i dont have the right tools. and i have looked at the air filter and it is clean, now i havnet checked the maf which i will do tomorrow, good idea. i will try to keep yall updated

Do not touch or place anything inside the MAF housing. Remove it from the CAI by removing the two screws. Handle on the outside only. Use a MAF cleaner spray and let it dry. There is a fine wire that heats up inside. It’s easily broken if touched. Just spray and let dry per instructions on the can and reinstall it.

[EpsilonMSP3]

Originally Posted by MSMS3 Do not touch or place anything inside the MAF housing. Remove it from the CAI by removing the two screws. Handle on the outside only. Use a MAF cleaner spray and let it dry. There is a fine wire that heats up inside. It’s easily broken if touched. Just spray and let dry per instructions on the can and reinstall it.

the CAI is the air filter or the big blue pipe, its blue for me bc its a cobb intake

[MSMS3]

Originally Posted by EpsilonMSP3 the CAI is the air filter or the big blue pipe, its blue for me bc its a cobb intake

Is this what you have? This is Cobb’s short ram intake:

https://www.cobbtuning.com/products/...eed3-2007-2013

Or this, their airbox intake:

https://www.cobbtuning.com/products/...eed3-2007-2009

Neither is a true CAI. Both do have a section after the filter that has a built in air straightener and then the mount for the MAF sensor. That sensor has a socket and wire plug. That sensor is held by two screws. Remove it to clean.

I’m beginning to sense that these things may be beyond what you should tackle on your own. If so, that’s ok. You may need some local help.

[EpsilonMSP3]

Originally Posted by MSMS3 Is this what you have? This is Cobb’s short ram intake: https://www.cobbtuning.com/products/...eed3-2007-2013 Or this, their airbox intake: https://www.cobbtuning.com/products/...eed3-2007-2009 Neither is a true CAI. Both do have a section after the filter that has a built in air straightener and then the mount for the MAF sensor. That sensor has a socket and wire plug. That sensor is held by two screws. Remove it to clean. I’m beginning to sense that these things may be beyond what you should tackle on your own. If so, that’s ok. You may need some local help.

the spark plugs that werent gapped by me, were gapped to .050, but i fixed them and now the car is running much much better than i could have ever asked for, thankyou for all yalls help!!!!!!