I just finished reassembling my freshly rebuilt street ported engine, and upon cranking I had compression, but I was getting a high pitched buzzer. I inspected the spark plugs and they were very oily/dirty. I set a plug up so that it would arc to check to see if I was getting a spark got nothing. I checked this with both the leading AND trailing coils with the same result; no spark. Are both my coils broke, or did I miss some crucial ground that makes them work? Any help would be appreciated!

 

The Black/Yellow wire at each coil powers the coils. Check the B/Y wire at the leading coil w/key to on and verify that you have 12 volts. Also, check the Black/White wire at a check connector plug w/4 wires near the lead coil (other wires in the the plug are Yellow based). The B/W wire should also have 12 volts w/key to on. This wire powers the ECU. And is your car an S4 or S5? The coils ground through their being bolted to the fender. If the grounding is poor they will not work.

 

It's an s4 tii swapped into an na and thanks

 

forget to plug in the CAS?

 

Or stab it?

 

Cas was plugged in

 

are you getting fuel without spark or are you without both?

 

Ok so I checked the fuel return line for fuel and it had none, so I checked the fuel line from the fuel filter and it had fuel in it. I also checked to see if the coils were getting power, which they weren't. I then found that my main starter relay had been unplugged at some point, so I plugged that back in and the coils were getting power again! I then checked the coil pack resistance and found that both leading AND trailing coil packs had huge amounts of resistance, along with one set of spark plug wires, so I will have to replace them.