P0301 p0305

Just took my car to autozone and it threw these codes out. BRAND new spark plugs. I'm also not very familiar with the ignition coil packs. any ideas?

oh and the codes are for misfires in cylinder 1 and 5

Originally Posted by dstu

oh and the codes are for misfires in cylinder 1 and 5

Clear them and see if they come back. Could be anything from bad gas to bad coil packs, to a crack in your intake elbow, to the MAF. Without other codes you will have a hard time narrowing it down.

i am not sure how to completely clear the codes and its kind of been a recurring problem and i often loose torque and hp randomly at starts so something is definaltey wrong but what will make it give me more codes than i already have?

Originally Posted by dstu

i am not sure how to completely clear the codes and its kind of been a recurring problem and i often loose torque and hp randomly at starts so something is definaltey wrong but what will make it give me more codes than i already have?

I dont know. The code reader can clear the codes for you. Let me give an example. I just had a lady whose BMW had p0301, p0304, p0305 codes or 3 of 6 cylinders mis-firing. Hard to diagnose, BUT it also had p1250 and p1423 codes (emission codes and fuel systme codes) so I had at least some idea of where to start. In my case I found it to be a torn intake boot (which connects the MAF to the throttle body) and that caused the plugs to foul out. Replaced the boot, replaced the plugs, problem solved codes went away.

JUST misfire codes will be tough to diagnose because a LOT of stuff can cause that. I'd start with checking your plugs (free), checking your intake boot (free) and cleaning your MAF ($5 for MAF cleaner). See what that does for you.....

I must've been completely out of it yesterday but the real codes on my autozone printout are P1353, P1351, P1345 and P1343 which it says it a misfire in cylinder with fuel cut off, does that change anything from me originally saying P0301??

Originally Posted by dstu

I must've been completely out of it yesterday but the real codes on my autozone printout are P1353, P1351, P1345 and P1343 which it says it a misfire in cylinder with fuel cut off, does that change anything from me originally saying P0301??

I dont recognize those codes.

uh oh....

Originally Posted by dstu

I must've been completely out of it yesterday but the real codes on my autozone printout are P1353, P1351, P1345 and P1343 which it says it a misfire in cylinder with fuel cut off, does that change anything from me originally saying P0301??

Found this but I don't know if it will help
P1351 IDM Input Circuit Malfunction/ Ignition Coil Control Circuit High Voltage
P1353 Ignition Coil B Primary Circuit Malfunction
P1343 Misfire Cylinder 1 With Fuel Cut-off
P1345 Misfire Cylinder 2 With Fuel Cut-off

Isn't there a way to clear codes without a code reader?

Originally Posted by phoenixreborn

Isn't there a way to clear codes without a code reader?

Nope.

Originally Posted by troubled

Found this but I don't know if it will help
P1351 IDM Input Circuit Malfunction/ Ignition Coil Control Circuit High Voltage
P1353 Ignition Coil B Primary Circuit Malfunction
P1343 Misfire Cylinder 1 With Fuel Cut-off
P1345 Misfire Cylinder 2 With Fuel Cut-off

Or in other words, "hard as heck to nail down what the problem is"

Originally Posted by smolck

Or in other words, "hard as heck to nail down what the problem is"

yea ...but i checked my intake tube, seems fine. I clean the MAF sensor and i checked out the coils and plugs, but to be honest i'm not really sure what i'm looking for in them, i mean the conections seemed fine and nothing looked out of the ordinary. I think i may go for a fuel filter change next. How does that sound

Originally Posted by dstu

yea ...but i checked my intake tube, seems fine. I clean the MAF sensor and i checked out the coils and plugs, but to be honest i'm not really sure what i'm looking for in them, i mean the conections seemed fine and nothing looked out of the ordinary. I think i may go for a fuel filter change next. How does that sound

Probably wouldnt hurt to change fuel filter. But try this. Since cylinder 1 and 5 are misfiring take the #1 coil and exchange it with the #2 cylinder. Then replace the #5 coil with the #6 coil. Now go have the codes cleared and re-read (you must clear them or it wont work!) See if you get a p0302 and p0306. If the codes follow the coils then they are bad. I just did this test on another BMW and i isolated a bad coil pack. When I was done it ran like a champ. Best part is the test only takes a few minutes and is free.

The cylinder closest to your radiator (or front of car) is #1 and the one in the back by the firewall is #6. Let me know....

thanks for the info!! this inspires me to do my own work as soon as i can borrow a code reader locally!

Had a bad miss number 5 coil was bad replaced all coils and plugs.Still ran bad pulled codes came up with P0102,P0113, P0305 and P0303.After checking all codes and looking for problems. found it.Do not rely on coil locks to install wires make sure all are pushed in all the wayby hand. All codes went away.

Sounds like a bad coil to me. Switch the coils, see if the code follows.

you can also check the resistance on the coils with a DVOM... primary circuit should be 0.5 ohms and the secondary circuit should be around or a little less than 6k ohms... but i would defiantly check the wire connections and try juggling the coils around on the engine like rccuda and smolck have instructed. BTW what plugs are you using? Any signs of cracked boots where the spark may be shorting?