You may have a wire concern, Rave time

 

Tough part about this whole process...is the fact we have no previous information about this engine. Me, if l were in this position...l'd head back to the beginning...of engine diagnostics. And since it seems to be consistent with codes, which is a good thing...l'd pull the plugs and do a compression test at this point. I'd need to know the mechanical soundness of engine...especially, to move forward looking at other posibilities. If l noticed any irregularities in the compression test, next would be a cylinder leakdown test. If compression test is good, and since you've changed/tested coil packs/wires/plugs, and since you aren't getting any vacuum or 02 related codes...my next best guess would take me to the injectors. I know you said the injectors were new, so look at harness or plug issues.

Brian.

 

Did new injectors.

the compression looks decent to me, I also noticed new ARP studs were installed.

Compression test results:
2: 120 (new spark plug dirty w carbon)

4: 120

6: 130

8: 140 (dirty)

1: 135

3: 135 (Dirty)

5: 120 (Dirty)

7: 140

 

Could it be bad O2 sensors causing the misfire?

I’ve read it has helped others with their codes but I’m not getting any O2 codes.

With no check engine light I ran the scanner and get the 1514 code and 1553. Rev the engine and I get the 1,7,4,6 misfire with 1300. No other codes.

Checked all the relays and grounds once more.

 

Bought another disco, at least that one works. Anyone have any trouble shooting ideas for getting cylinders 1,4,6,7 to spark? I really want resolve this misfire

 

black one is sweet! I think you hit the just a few of the usual suspects. check the CPS and MAF. Check spark plug wire order. Look for melted wires, broken insulation, dirty connectors, bad grounds (engine,fusebox,inside)....

 

Found the problem, I had a broken wire. Misfires are gone, still only starts in park sometimes but oh well, thanks for your help everyone.