Hey guys!
Hopefully somone can help me with this hella problem i have its a brain buster.
:confused:
Me and my friend are building a 92' 240sx with a redtop sr-20-det.
The motor is in the car and has fuel going to the fuel rail
We have spark on cylinders 1,2, and 4
cylinder 3 continues not to have spark

-we tested the voltage to all 4 of the coil packs, all of them had voltage around
12 volts, to the center connector of the 3 prong clip

-There was about .6 ohms on the passenger side pin. of the coil pack (i dunno if this matters because it was similar through all 4 connectors)

-We switched the coil packs from 2 and 3 to make sure it wasnt the coil pack, and still continue to get no spark in 3 but the coil pack works.

-As far as tracing the problem to the ECU we back probed cylinder 3 (pin 8 r/g wire)and tested resitance to the coil pack. about .6 ohms

-I know the ECU and ignitor chip, are not faulty because im using a brand new ones that work in another SR.

-We also reset the CAS sensor and still no spark in 3

-When we crank the engine it just backfires.

-we are using 440 cc injectors (could it be flooding?)
-SOME ONE HELP ME START THIS BITCH! PLEASE!!!

Let me know guys!!

the ecu controls the ignitor to make the cylinder spark. You can go directly to the ignitor and look for cyl #3 control on the pcm side or control side of the ignitor you should have dwell at that wire. you measure dwell with a dvom put the black lead on ground the red lead on the wire you are testing and it should read anything but OL while cranking. if you dont have any dwell then you have a bad pcm or wiring issue from pcm to ignitor. good luck Mike

Check the plugs if there wet with fuel. i had the same problem before and it was my o rings

Let's keep your question to one thread... and the one in the 240 section is probably a better location for this type of question.

http://www.sr20forum.com/240sx/197886-no-spark-cylinder-3-a.html