...and my car still misfires, please help :(

please bear with me while i explain my story. ok, so about a year ago my lovely 330ci started to misfire and during idle the rpm needle would constantly move up and down until the car would eventually shut-off. so i took it to a local bmw shop and had a diagnostic on it and they came back with about $3000 worth of work, which i dont have laying around my house. they also did not report anything wrong with my camshafts (which come into my story later). i ended up replacing the DISA valve, idle control valve, crank case vent valve, thermostat, and had a tune up all done by a separate mechanic shop. those repairs solved the idling problem but not my misfire problem. after they did some work, they said i had white spots on my camshafts and the lifters were worn down, causing the misfires so i needed to replace the camshafts, lifters, valves, and intake manifold (basically the whole valve train). when the car is running you can hear clicking noises that sound like it could be the valves but the first shop said nothing about any of this and i did not drive my car at any point between the diagnostics and repairs. now the funny thing is, ive driven the car for about a year and the problem hasnt gotten worse or better, but here is the reason why ive been able to drive it for so long (very interesting in my opinion).

when i first start my car, it doesnt misfire right away but it will idle at about 1000 rpms (a little higher than normal) and will rev normal unlike it does after it starts to misfire. i let my car idle so the engine will warm up, i always do this before i drive my car. it starts to misfire once the car's rpm needle idles at its normal position (around 500 rpms). once my car has warmed up, i turn it off for about 5 seconds, turn it back on, put it in first gear and drive away. the reason i do this is because right after i turn my car off and back on, it doesnt drive like it does when it misfire, it drives normal. even when im driving it wont misfire. the only time the engine will misfire is when it idles without given any gas. so everytime im at a stoplight, im constantly revving my engine to about 1000 rpms so it will drive normal and not crappy like it does when it misfires. but if im at a stoplight and dont rev the engine, after about maybe 7-10 seconds later you can feel the engine shake as it starts the misfire, causing me to turn the car off and back on before the light turns green.

i dont know if this helps but my air conditioning/heater doesnt always work. it may be turned on, but will not always blow out air and when it does it blows out hot air, or warm if i set it to cold, at full blast, even if its not set at full blast. and the air conditioning doesnt work at all.

im going to get a diagnostic once i get my tax return, but i want to know what your guy's opinion is of my situation. any information is much appreciated. thanks guys

First of all, you are not supposed to let your car idle to warm up. Your owner's manual even tells you so. You have likely fouled your 02 sensors by doing this and maybe your cats. Does your car give you a check engine light when this is happening? If so, have you read the codes to see what they are?

Oh, and the camshaft thing is total crap.

Just curious, does your car consume any oil?

My first reaction would be when it misfires does it set the check engine. Plus what cylinders are misfiring? I would take a look at your coils, also I would inspect the spark plugs, I have had cars roll into my dealership that other butcher shops jam the four prong spark plugs down into the cylinder and damage the spark plug.

lol

i have to let my car warm up or the engine will run really really bad. my check engine light has been on since i had everything replaced. i figured it was because of the camshafts.

my car consumes oil like a whale does water lol. lets just say when i get my oil changed, i get told that not alot of oil came out, so yea it does. should have included that in the original post.

i had the codes ran awhile back so i dont really remember but i think it was something like lean banks in one and two, and i think misfire in 5th and 6th cylinder. not positive but i know it came up with some misfires. ill need to go check them again.

There are many things that can cause a misfire.

Maybe the VERY best of E39 Links misfire-diagnostic tree can help you for your E46?

- How to diagnose a BMW E39 engine misfire (1) & a cold-engine intermittent misfire (1)

1. bad fuel [air:fuel ratio]
2. clogged fuel filter [air:fuel ratio]
3. bad fuel pump [air:fuel ratio]
4. clogged engine air filter [air:fuel ratio]
5. vacuum leaks in hoses [air:fuel ratio]
6. bad coil packs [spark]
7. bad coil boots [spark]
8. bad or ill fitting spark plug valve cover seals [spark]
9. worn or fouled spark plugs [spark]
10. bad mass air flow (MAF) sensor or meter [air:fuel ratio]
11. bad DISA valve flap [air:fuel ratio] (1)
12. bad DISA valve o-ring [air:fuel ratio] (1)
13. worn fuel injector seals (o-rings) (1) (2)
14. bad fuel injectors [air:fuel ratio]
15. bad 02 oxygen sensors [air:fuel ratio]
16. cracked rings [compression]
17. bad camshaft position sensor CMP, aka CPS [spark? timing?]
18. bad crankshaft position sensor CKP, aka CPS [spark? timing?]
19. bad ground wires [spark]
20. bad fuse or relay [gas, spark, timing]
21. bad electrical wiring [gas, spark, timing]
22. bad engine computer DME, aka ECU [spark]
23. intake manifold gasket leak [compression, air:fuel ratio]
24. bad crankcase oil separator valve CCV, aka PCV [air:fuel ratio]
25. bad idle control valve ICV [air:fuel ratio]
26. bad throttle position sensor TPS [air:fuel ratio]
27. bad VANOS seals [compression, air:fuel ratio]
28. head gasket leak, or a cracked block [compression, air:fuel ratio]

Originally Posted by BROK3N

i have to let my car warm up or the engine will run really really bad. my check engine light has been on since i had everything replaced. i figured it was because of the camshafts.

my car consumes oil like a whale does water lol. lets just say when i get my oil changed, i get told that not alot of oil came out, so yea it does. should have included that in the original post.

i had the codes ran awhile back so i dont really remember but i think it was something like lean banks in one and two, and i think misfire in 5th and 6th cylinder. not positive but i know it came up with some misfires. ill need to go check them again.

This is the most disconcerting post I have read in some time.

This sounds like a case of poor maintenance and lack of knowledge on how to keep these cars running well.

^^thanks for the help kunal . not everyone knows everything about engines, hence why i posted on here because im trying to find some answers, not you havent maintained your car. i maintain my car as much as possible, but as a broke college kid, sometimes bmw parts are pretty expensive. im going to get the codes ran this afternoon and post them on here.

ok so on my way home this afternoon i stopped by autozone to use their scanner. these are the codes i got:
P0313 - Misfire Detected Low Fuel Level (had a little less than a quarter tank of gas at the time)
P1353 - Manufacturer Control Ignition System or Misfire

hope this helps guys. thanks

those are the only two faults in the car??? we a veh running as bad as you say I was guessing atleast 5 or 6 faults

Originally Posted by BROK3N

ok so on my way home this afternoon i stopped by autozone to use their scanner. these are the codes i got:
P0313 - Misfire Detected Low Fuel Level (had a little less than a quarter tank of gas at the time)
P1353 - Manufacturer Control Ignition System or Misfire

hope this helps guys. thanks

I love those autozone guys and their attempt to explain a code.

The 1353 is misfire with fuel shutoff for cylinder #6. You are loading up on fuel and the car is cutting fuel to that cylinder. I'm thinking the injector for # 6 might be bad, or your coil is bad or the plug. Pull your #6 plug and look at it, is it fouled? If not switch #5 coil with #6 coil and see if the code follows it. If it does then you likely have a bad coil (this is my gut feeling).

Oh, cylinder # 6 is all the way at the back. They are numbered 1-6 from the bumper to firewall.

Originally Posted by smolck

I love those autozone guys and their attempt to explain a code.

The 1353 is misfire with fuel shutoff for cylinder #6. You are loading up on fuel and the car is cutting fuel to that cylinder. I'm thinking the injector for # 6 might be bad, or your coil is bad or the plug. Pull your #6 plug and look at it, is it fouled? If not switch #5 coil with #6 coil and see if the code follows it. If it does then you likely have a bad coil (this is my gut feeling).

Oh, cylinder # 6 is all the way at the back. They are numbered 1-6 from the bumper to firewall.

+1 I am with smolck

Originally Posted by BROK3N

but as a broke college kid,

Sorry man, but a BMW is the WRONG kinda car for a broke college kid, unless you're going to BMW Auto Repair College, this is your project car, and your tuition is paying for the parts.

I'd say dump this heap and get a Civic or Corolla. College is a time to be worrying about your grades and getting laid, not about your damn car!

The time to impress chicks (or dudes) with your hot car is AFTER college, when you have a job.

hahahahaha thanks guys. i just want to get it fixed and trade it in and get a honda s2000, they are relatively cheap in my area. honda parts are so so so cheap compared to bmw parts. i couldnt imagine how much M3 parts are. but i love my 330ci, itll be hard to let it go (if i can ). ill post back hopefully this weekend when i get a chance to check out the coils and such.

Originally Posted by smolck

Oh, cylinder # 6 is all the way at the back. They are numbered 1-6 from the bumper to firewall.

The misfire diagnostic tree has a description of the cylinder locations and firing orders for the E39.

Are these the same for the E46?

V8 M62, M62TU, Firing order... 1-5-4-8-6-3-7-2

• Rear of engine
  • 4-------------8
  • 3-------------7
  • 2-------------6
  • 1-------------5
• Front of engine

i6, M52, M52TU, M54, Firing order... 1-5-3-6-2-4

• Rear of engine
  • 6--------------
  • 5--------------
  • 4--------------
  • 3--------------
  • 2--------------
  • 1--------------
• Front of engine

Originally Posted by mrblorry

a BMW is the WRONG kinda car for a broke college kid, unless you're going to BMW Auto Repair College, this is your project car

While I can't disagree with you (since the BMW breaks a lot in places that just shouldn't be breaking) ... in a funny way ... a BMW is a PERFECT car for a college kid.

If he had a Lexus LS400 or an Infiniti Q45, it would never break as much as his BMW - not even close - and he'd never get a chance to LEARN first hand how a problem is looked at.

For an example of how a college kid can benefit from a BMW, see this caveat lector:
- Response written to a 19-year-old college kid trying to explain why DIY is a good way to go if he owns a BMW.

Originally Posted by BROK3N

hahahahaha thanks guys. i just want to get it fixed and trade it in and get a honda s2000, they are relatively cheap in my area. honda parts are so so so cheap compared to bmw parts. i couldnt imagine how much M3 parts are. but i love my 330ci, itll be hard to let it go (if i can ). ill post back hopefully this weekend when i get a chance to check out the coils and such.

BMW parts ain't that expensive buddy. My wife's Jeep Cherokee parts are more than my BMW.

Originally Posted by bluebee

Are these the same for the E46?



i6, M52, M52TU, M54, Firing order... 1-5-3-6-2-4

• Rear of engine
  • 6--------------
  • 5--------------
  • 4--------------
  • 3--------------
  • 2--------------
  • 1--------------
• Front of engine

No V8 option for the E46 (unfortunately) but the 6 is the same.

I agree with smolck my wifes wrangler parts are through the roof with mark up with a little research on the web you can find oem BMW parts for a good deal, remember hondas lexus and toyotas still have to pay import taxes too (is many lexus, lexi??? lol)

yea thats very true. i have learned so much from working on this car, which is good because i dont really have anyone to teach me and i enjoy learning from hands on and experience. but here is the deal, i ended up replaced the 6th cylinder coil after i had tested them. now when i replaced the coil i didnt replace the spark plug, because i didnt have enough money for the spark plug (broke college kid remember). but once i was replaced it ran a little bit better, it still misfired but it was actually harder to tell. i heard somewhere that i could possibly be the fuel pump but im thinking maybe the spark plug. any suggestions guys? thanks!!