300zx engine light! help!

[RBrum]

so the other day i noticed the engine light came on when i came to a stop i proceeded to go noticing an extremely bad rumble. its coming from cylinder #3 im pretty sure ive been told that it sounds like a weak coil pack but i have no idea. then again i heard it could be a vacuum leak or intake. but any suggestions or anything would be helpful. its a 94 300zx n/a. the engine light goes on an off at random times but when its on the car rumbles really bad and runs terrible but once it turns off its fine again... i dont know alot about this car so anyones input would be helpful if it could save me some money. also heres a video if u can hear the difference. http://www.youtube.com/watch?v=ZidCTn3NLYY&feature=channel_page

in kind of has a ting to it sounds funny

[ericnjttz]

http://www.ttzd.com/tech/diagnostictech.html

do that...figure out the code and go from there.....could be a coil. you could swap it with another and see if the miss changes cylinders, if not injector possibly.

[RBrum]

alright ill see how it goes thanks

[a2low240]

Injector or Coilpack, they both fail often on these.

[RBrum]

im hoping its that and not somthing major

[AztecTT]

Hm...I've had injectors and coil pack connector wiring crap out on me - have never got the "check engine" light for either (this was between two Z's).

But yeah, what did you get when you pulled the codes (Eric's post)? If the check engine light is going off, that will definitely tell you something that is wrong.

If you're too lazy to pull off the wood panel to get to your ECU: http://www.twinturbo.net/ttnetfaq/FAQpages/ECUdiagnostics.html

[JKZ]

First time i saw this...
I run Ryans, codes last night and got a code 51 "injector circuit" Told him to see if there loose and plug them in all the way or they might be corioded and need to be cleaned.
When he got home he said you was push the clips down and the engine light would go off then on, so i think they might just be dirty.

[zerioustt]

simplest way is to pull coil packs one by one while the car is running. if you pull one and it gets worse its not that coilpack, if you pull one and nothing changes there is your pack thats bad. takes 2 seconds...