Coilpack Or Injector ?

[hisoka]

hey SAU'ers, nissan noob here.

i have just engine swapped a rb20 into my silvia. and i have a slight problem

the cyclinder 5 is not working. now my question to you guys is what is a good way to check wether my coild pack needs replacing or the injector.

i have yet to swap around coilpacks, i have just got new spark plugs but the old ones seem to be good (blitz brand and good colour) except for cyclinder 5 which is black.

from this observation am i alright to assume that there is fuel getting in but no spark occuring.

the car is pulled apart at the moment and i thought id post on here before jumping into it.

there is another thread just like this one and i got some good info from it, but just wondering if my assumption on the spark not firing is correct judging that the plug itself has tuirned black

thanks for any replies

[krzysiu]

Easy test. Remove the coilpacks plug from cylinder 5 and fire it up. If the car runs the same (like crap) that's your problem

[hisoka]

Easy test. Remove the coilpacks plug from cylinder 5 and fire it up. If the car runs the same (like crap) that's your problem

i did this already to work out that cyclinder 5 is the one with the problem, as i removed plug and the sound did not change.

but is this for sure mean the coilpack is damaged ? couldnt it be fuel injector

[blind_elk]

A black spark tip usually signifies poor combustion, rather than no combustion.

Do you have compression in #5? Poor compression could cause poor combustion of the air/fuel mix.

Clean #5 plug, to make sure it will fire correctly (if it's going to fire). Swap #5 coil with another cylinder, and observe which cylinder now has the problem.

[paulr33]

i like how you say "just" and a "slight" problem

dude youve done a complete engine swap., there could be a million things wrong

check basics, recheck your wiring , plugs, run stock ecu diag, check all wiring, check all sensors

[hisoka]

i like how you say "just" and a "slight" problem

dude youve done a complete engine swap., there could be a million things wrong

check basics, recheck your wiring , plugs, run stock ecu diag, check all wiring, check all sensors

thanks for the help guys

to list iam going to do a compression check first before anything and then a coil pack swap with the other cyclinder. and use the new ngk plugs i got.

i checked the wiring today, and iam about to do a ohms test on my 5 cyclinder coilpack so i will post results, if this is even possible lol.

Blind_elk: thanks for that info, i will check compression asap and coil swap. atm i just wanna kill myself, i broke the peice of shit connector ontop of coil 4 lol. so i gotta get one of those and solder it on

paul r33 if your who i think you are, thanks for all the topics you had. i read alot of your posts, never thought id ever talk to you lol.

iam usually on nico forum, and they refer to most of your posts from that website you had. they love RB's

i have done stock ecu diagnostics, returning a code 55. so yeah no help there from stock ecu. if it was wired wrong it would return what error but ? ignition ?

thanks guys.

edit. how bad is it ive been driving the car for a while, about 4 days? ...and kinda drifting everynight for 4 nights since ive finished the swap

didnt even really notice because i daily a wrx with a exhaust LOL. my hearing is already quite impaired from this lol

Edited April 4, 2010 by hisoka

[Kwyjibo]

If you've got an ignition lead just plug it in between the spark plug and shove the other end in the coil, and use a timing light on it, if its flashing you have spark. Could also unplug the fuel pump, start the car until it stalls, then take out the spark plug and ground it against something while turning the car over. You should be able to see a spark. Otherwise its likely to be a fuel issue.

[hisoka]

If you've got an ignition lead just plug it in between the spark plug and shove the other end in the coil, and use a timing light on it, if its flashing you have spark. Could also unplug the fuel pump, start the car until it stalls, then take out the spark plug and ground it against something while turning the car over. You should be able to see a spark. Otherwise its likely to be a fuel issue.

lol thanks man. why didnt i think of this.

will do this

[soturi]

+1 for compression test, this is a dead ringer of my old rb25 vl..... cylinder 5 too.....

[hisoka]

+1 for compression test, this is a dead ringer of my old rb25 vl..... cylinder 5 too.....

what was end out come ? rebuild ?

[hisoka]

hey guys. for future reference to anyone who thinks they have a coilpack gone and have not been able to swap with other cyclinder.

the easiest way, is to get a multimeter and do a ohms test on positive and negative. the reading will be open line.(no resistance)

i can confirm this works, as today i found out that my coilpack has no resistance. this is the damaged coil pack. my working one

has a resistance.

thank you guys for help. and now heres another way you guys can tell people to check packs, it takes 10 seconds. cheers

Edited April 5, 2010 by hisoka