Miss Fire!! - Tuner-Junction

triniskill · #1 (**permalink**) August 2nd, 2006, 02:08 AM

my b16 is misfireing....#2 cyclinder is misfirin..I thought it was my injectors..soo i changed them..didn't work....chagned and checked all grounds..change spark plugs...and still nothing worked...I got the car fired up..runin on 3 cyclinders and then after I checked the the spark plugs and all of them show a sign of its workin besides bumber 2...IDK wuts wrong with it..I need to do a compresion check soon..

#2 (**permalink**) August 2nd, 2006, 03:02 AM

your still having problems? So it wasnt the fuel injector grounds................

triniskill · #3 (**permalink**) August 2nd, 2006, 09:41 AM

yea its still

but I'll figure somtin out..
If anyone has any ideas..please say someting..

A_White_Gs-R · #4 (**permalink**) August 2nd, 2006, 10:15 AM

check your dizzy. check the cap and the the ignition wires as well.

Disillusioned · #5 (**permalink**) August 2nd, 2006, 11:00 AM

misfire?

ATISTANG · #6 (**permalink**) August 2nd, 2006, 11:15 AM

Quote:

Originally Posted by Disillusioned

misfire?

It means there is no explosions going on due to lack of spark and/or fuel and/or compression and/or timing

triniskill · #7 (**permalink**) August 2nd, 2006, 11:26 AM

Quote:

Originally Posted by A_White_Gs-R

check your dizzy. check the cap and the the ignition wires as well.

yea thats wut im checkin now...I changed my wires and that didnt help..If I find anything wrong wit this dizzy i got a extra one on stand by..

Disillusioned · #8 (**permalink**) August 2nd, 2006, 11:28 AM

Quote:

Originally Posted by ATISTANG

It means there is no explosions going on due to lack of spark and/or fuel and/or compression and/or timing

i know what it means. i was actually correcting his spelling.

triniskill · #9 (**permalink**) August 2nd, 2006, 11:31 AM

Quote:

Originally Posted by Disillusioned

i know what it means. i was actually correcting his spelling.

LOL...i did spell it wrong...

ATISTANG · #10 (**permalink**) August 2nd, 2006, 11:32 AM

Quote:

Originally Posted by Disillusioned

i know what it means. i was actually correcting his spelling.

Liar

triniskill · #11 (**permalink**) August 2nd, 2006, 11:37 AM

Ok checked dizzy..I'm getting spark to all cyclinders..My bro said it could be my compressin ring..

...I need to do a compression test asap...

ATISTANG · #12 (**permalink**) August 2nd, 2006, 11:43 AM

Quote:

Originally Posted by triniskill

Ok checked dizzy..I'm getting spark to all cyclinders..My bro said it could be my compressin ring..

...I need to do a compression test asap...

Yes you do
Could also be a burn't valve and that is a more likely cause.

triniskill · #13 (**permalink**) August 2nd, 2006, 11:49 AM

I hate how this is going right now...

triniskill · #14 (**permalink**) August 2nd, 2006, 07:11 PM

ok..soo i did a compression test..between 180-190 on all cylinders...now my question is can a idle air control..cause a misfire..can it mess the air/fuel mixture up..cuz my idle doesnt stay its just drops..my tps is good..I;m goin to get a different idle air control valve tomrow too c if that will change things...I hate this shit..

A_White_Gs-R · #15 (**permalink**) August 2nd, 2006, 09:07 PM

clogged injectors can also cause it. if theres no gas to explode in the cylinder then there you go misfire.

triniskill · #16 (**permalink**) August 2nd, 2006, 09:10 PM

Quote:

Originally Posted by A_White_Gs-R

clogged injectors can also cause it. if theres no gas to explode in the cylinder then there you go misfire.

I changed them...still didnt work..

A_White_Gs-R · #17 (**permalink**) August 2nd, 2006, 10:14 PM

theres gotta be soemthing so simple that everybody is missing it.

triniskill · #18 (**permalink**) August 2nd, 2006, 10:22 PM

Quote:

Originally Posted by A_White_Gs-R

theres gotta be soemthing so simple that everybody is missing it.

yea i no its somthing simple thats wrong with it but just cant figure it out..

jadkar · #19 (**permalink**) August 2nd, 2006, 11:02 PM

OK.....this thread must be what you were talking about before

1. Check every spark plug one by one. Take all the plug wires off the plugs, unhook all the injector clips (this way your not dumping fuel into the cylinders during this test). Plug one spare spark plug into a wire and ground the plug thread to something metal and have someone crank the engine, look for spark (watch out for any fluid that can ignite!!). Write down your results in a notebook to keep track of what your doing. Move to the next cylinder and do the same. Once you have confirmed you have spark in all the cylinders you can mark cap, rotor, igniter, coil, wires off your checklist.

2. Next I would move to fuel. Our injectors are negative firing, meaning they always have current going to them and the ECU just grounds each injector one at a time to trigger them. So what I would do is check to make sure you have voltage at each injector plug when the ignition is in the on position. The wires to check for voltage are red/blk (at least on the SI harness). There should be a Red/blk wire for each injector, this is the positive feed to the injector. So you would check current between the red/blk wire and ground (like the chassis). If you have voltage at each injector with the ignition on then check voltage again but this time between the red/blk wire and the other wire in the injector clip. This time you should get no voltage. Remember to write down all your findings. At this point if everything checks out I would doubt that your issue is the injectors. It could still be a bad ECU or a clogged injector (but you replaced the injectors). The other thing that would make this test complete is to get a stethoscope and listen to each injector while the car is idling, you will hear a definitive "click" as the injector is pulsing.

3. Leak down test. I know you already did a compression test and this maybe over-kill but I would do it anyway. You never no you could have a slightly stuck valve that might not show up in a static compression test.

4. Leave your problem cylinder injector plug unhooked as well as the spark plug boot off the plug and see if the problem gets worse or stays the same. By doing this we can see if you are truly misfiring all together or just having weak combustion in that one cylinder.

Have you noticed..........
Does it get better with throttle or worse?
When did this start?
How's you cam timing?

I don't think this is your IACV. I'd like to know for certain if you are definitely missing on one cylinder or multiple cylinders and it just sounds like one. Step number 4 will determine that.

Let me know, also if you don't understand the injector tests LET ME KNOW. I don't want you shorting out your wiring!!

triniskill · #20 (**permalink**) August 3rd, 2006, 12:08 AM

Quote:

Originally Posted by jadkar

OK.....this thread must be what you were talking about before

1. Check every spark plug one by one. Take all the plug wires off the plugs, unhook all the injector clips (this way your not dumping fuel into the cylinders during this test). Plug one spare spark plug into a wire and ground the plug thread to something metal and have someone crank the engine, look for spark (watch out for any fluid that can ignite!!). Write down your results in a notebook to keep track of what your doing. Move to the next cylinder and do the same. Once you have confirmed you have spark in all the cylinders you can mark cap, rotor, igniter, coil, wires off your checklist.

2. Next I would move to fuel. Our injectors are negative firing, meaning they always have current going to them and the ECU just grounds each injector one at a time to trigger them. So what I would do is check to make sure you have voltage at each injector plug when the ignition is in the on position. The wires to check for voltage are red/blk (at least on the SI harness). There should be a Red/blk wire for each injector, this is the positive feed to the injector. So you would check current between the red/blk wire and ground (like the chassis). If you have voltage at each injector with the ignition on then check voltage again but this time between the red/blk wire and the other wire in the injector clip. This time you should get no voltage. Remember to write down all your findings. At this point if everything checks out I would doubt that your issue is the injectors. It could still be a bad ECU or a clogged injector (but you replaced the injectors). The other thing that would make this test complete is to get a stethoscope and listen to each injector while the car is idling, you will hear a definitive "click" as the injector is pulsing.

3. Leak down test. I know you already did a compression test and this maybe over-kill but I would do it anyway. You never no you could have a slightly stuck valve that might not show up in a static compression test.

4. Leave your problem cylinder injector plug unhooked as well as the spark plug boot off the plug and see if the problem gets worse or stays the same. By doing this we can see if you are truly misfiring all together or just having weak combustion in that one cylinder.

Have you noticed..........
Does it get better with throttle or worse?
When did this start?
How's you cam timing?

I don't think this is your IACV. I'd like to know for certain if you are definitely missing on one cylinder or multiple cylinders and it just sounds like one. Step number 4 will determine that.

Let me know, also if you don't understand the injector tests LET ME KNOW. I don't want you shorting out your wiring!!

I will do step 2 again tomrw just to make sure i didnt mis anything...the leak down test is gong to be my last option....thanks john