(OPEN STILL) My BMW keeps back firing, at low idle speeds, i wanna punch it

[92BMW318is]

okay guys ill try to explain this as best as possible,

i bought new spark plugs, so these autolite double platnuim spark plugs were installed in my car by me, and i turned the key to start my car and i heard a "POP POP BOOM" sound comming from the engine, turned it off i was thinking at the time that auto zone sold me the wrong plugs, so i took  out the new plugs and put the old ones back in, turned the key and heard the same "POP POP BOOM" sound, so i call autozone and ask them wtf was wrong with the new spark plugs and that the plugs were making my car miss fire and back fire, they told me this shit about how i crossed the ignition wires, which i didnt, then they told me that the spark plugs wernt pre gapped, then they told me to gap the new ones to 0.035 (I dont even know if that is right) so i gaped them to 0.035 and then "POP POP BOOM" once i started the BMW again.

sooooo now my car is probably all kinds of screwed up...

every time i take out the plugs they are covered with a black gas, (it isnt oil in the gas) looks like carbon build up or somthing.

so heres what i want to know:

1. what are the plugs on my car suppose to be really gaped too?
2. Since autozone say i crossed the wires to the plugs, can someone here supply me with a Picture of where and what wires plug into whitch plugs.
3. can i shop vacume the black gas out of the cylinder,
4. what are some ways to clean out black gas
5. is it okay to spray carb cleaner in cylinder.
6. WHAT is your input on my situation.

p.s what in the hell is a stomp test and will it be useful in my situation?

o and thanks for your help
WRONG


RIGHT





Thanks,
        BRETT

[dvmotorsports]

1. what are the plugs on my car suppose to be really gaped too?

Don't recall off the top of my head. However, dual diode plugs should be pre-gaped as it's not as easy to fit a gaping tool in there. I could be wrong, but I doubt it

2. Since autozone say i crossed the wires to the plugs, can someone here supply me with a Picture of where and what wires plug into whitch plugs.

There should be a black cover at the coil pack where the wires attach. It should have numbers on it. 1, 2, 3, 4. If not, while standing at the passenger side looking into the engine bay the coil pack will assume the shape of a square. The bottom right (closest to you on the right) will be #1. Bottom left #2. Top left #3. Top right #4. The matching cylinders go from radiator to firewall 1, 2, 3, 4.

3. can i shop vacume the black gas out of the cylinder,

Don't bother, it will push out.

4. what are some ways to clean out black gas

See #3
5. is it okay to spray carb cleaner in cylinder.

Yes. Spray it and then leave the plugs out so it's vents to the atmosphere for a few minutes. After that put your plugs in.

6. WHAT is your input on my situation.

Autozone is full of morons

p.s what in the hell is a stomp test and will it be useful in my situation?

Turn the key as far as you can without starting it. Push the accelerator down five times quickly. The check engine light will flash once and then start giving you flashes like mores code. Example blink pause blink blink pause blink pause blink pause will be code 1211.

Here is what the codes mean
http://www.scribd.com/doc/12801540/Bmw-Motronic-Codes

[dvmotorsports]

oh an put your old plugs back in and see what happens. nice picture btw picasso

[92BMW318is]

oh an put your old plugs back in and see what happens. nice picture btw picasso

but is that pic right, the coil and numbers

and thanks for all the useful info


also the plug has one diode

[dvmotorsports]

No. The motor is entirely backwards. And your coilpack doesn't sit inline

Engine
  34
  21
Fender

[92BMW318is]

No. The motor is entirely backwards. And your coilpack doesn't sit inline

Engine
  34
  21
Fender

im talking about just the coil and spark plug wire leads,

are the coils and spark plugs numbered right, do they match up like i matched them  in the picture, as in the first coil closest to the windshield lead to the first spark plug input closest to the windshield, so on and so on.

|windshield|
Coil|1-Spark|1
Coil|2-Spark|2      |engine|    |intake manifold|
Coil|3-Spark|3
Coil|4-Spark|4

|front bumper/ radiator|

[dvmotorsports]

[92BMW318is]

okay so i looked at the engine and this is what the coils look like on my car and this is how they are positioned is this the right order

[dvmotorsports]

Bingo!

[92BMW318is]

Bingo!

thanks brother

[AcSchnitzer318is]

awesome!  LOL, I'm pretty sauced and this made my night even better... lol jack and crown on special + this picture = win!

[DesktopDave]

Awesome...sorry I missed this thread!!  I love that pic...

This thread should be a sticky!

[92BMW318is]

i hooked up the plugs in the correct order and still, the engine back fires,
from what i can see when i took the other new spark plugs out and replaced them with newly newer pre gaped plugs, i shined a light down the spark plug shaft to see black carbon tar in the cylinder, now this is what i think is stalling out and making my car backfire but, the damn car wont start so i cant perform a "blow out",(rev engine high burn up excess carbon tarr).

so i think im left with one option. is to take apart the cylinder head cover,
oooo mannn is that going to suck.

if you guys have any other ways to do this besides taking off the header let me know,

ALSO, i know there are some gaskets im going to have to replace,
if you know what those gaskets are please include in your reply to this post,

ALSO #2,  is the cylinder head cover the only thing im going to have to take off to get to the cylinders to clean them out, whats the best way to clean them?



is removing cylinder head cover really nessicary, thats the only option i can see that would be plausable right now

#3. any special tools required?

 thanks again,

[tjts1]

I LOLed!

Ok this is just a guess. Your engine is running but its making crazy popping noises so at least 1 or 2 and probably 3 of the cylinders are firing as they should. There is a chance you could have damaged one of the spark plug wires in the process of changing the plugs. If the plug wire is damaged the unburned air fuel mixture from one of the cyls is igniting in the exhaust, hence the crazy noises. I don't know how to test the plug wires. Seeing how expensive the 4 foot+ long wires are, I'm betting they're pretty old (mine still had the cosmoline coating from the factory). Take a close look inside the connector at each plug wire. If you want to cheap alternative to M42 plug wires...
http://m42club.com/forums/showthread.php?t=5309
Again, this is just a guess.

good luck
Justin

[92BMW318is]

I LOLed!

Ok this is just a guess. Your engine is running but its making crazy popping noises so at least 1 or 2 and probably 3 of the cylinders are firing as they should. There is a chance you could have damaged one of the spark plug wires in the process of changing the plugs. If the plug wire is damaged the unburned air fuel mixture from one of the cyls is igniting in the exhaust, hence the crazy noises. I don't know how to test the plug wires. Seeing how expensive the 4 foot+ long wires are, I'm betting they're pretty old (mine still had the cosmoline coating from the factory). Take a close look inside the connector at each plug wire. If you want to cheap alternative to M42 plug wires...
http://m42club.com/forums/showthread.php?t=5309
Again, this is just a guess.

good luck
Justin

ill check on that forsure, but what about my last post before yours you have any ideas?