Coil Pack not sparking 2 wires

[rocket455]

so i figured out that 2 cyls are not firing. the 2 rear plugs on the coil pack are not giving off any spark at all. i tried replacing the coil pack but there is still no spark on those 2 wires. any ideas as to what would cause this?

p.s. i used the infamous search feature and found nothing

 

[1993MTXSHO]

bad connection on the coil pack or screwed up wiring harness is all I can think of other then coincidence that the pack you replaced your old one with also has those 2 bad.

 

[projectSHO89]

Your DIS module is probably bad. If you were to pull your codes (which you should have done), you'd likely get a COIL X fault.

I've never seen a coil go bad on a SHO engine (yet in 8 years). They are quite robust.

Steve

 

[Yamaha V6]

+1 on the DIS. I got no codes on mine, did a Cylinder balance test during the problems & it only identified 1 cylinder being whacked. I thought it was a coil pack issue, replaced the pack w/ a new Accel, did nothing for the problem. Replaced the DIS w/ a used one, everything's a-ok again. Problem was intermittent also, not consistent.

 

[Phoenix]

+2 on the DIS

 

[hawkeye18]

+3 DIS. Coil packs get weaker over time, but rarely do they outright fail.

Make sure you put heat sink paste on the new one.

 

[rocket455]

i have replaced the DIS module about 5 times and with every one of them it does not fix it at all, and yes i do put the heat sink on the back of them. with that said, here are the codes

KOEO
511-cause is the LPM

KOER
116- I dont know what this is, but i got it twice
159- MAF out of self test range
172/136- Whole engine is lean
332- EGR valve opening is not detected (i know my egr valve tube is broken)
225- Knock sensor not detected during dynamic response test

 

[hawkeye18]

116 = ECT out of self test range.

There are three wires going from the DIS to the coil pack - one for each coil. Check continuity of them to make sure they're not broken.

And yeah, an LPM or TwEECer will pop that 511, so good call on not worrying about that.

It sounds like you have massive vacuum leaks, possibly more than one, a bad MAF, and a bad ECT. And, now that I look it up, only the rear O2 is popping lean - both those codes are for the same bank. So, replace both your O2s (the other one isn't far behind), your MAF (and/or clean it with CRC MAF Cleaner), and your ECT sensor. That might help.

 

[rocket455]

ok, i replaced the fuel injector wiring harness and it fixed the sparking problem, but im done for the night and am going to check the codes tomorrow to see whats still there

 

[rocket455]

while warming up the motor for my KOER test, the engine failed on me. it turns over but with no spark at all to the coil pack. i first thought that it might be the DIS so i replaced that but still nothing. im going to check all connections to make sure none of the connections came unplugged or loose. other than that, does anyone have any ideas?

 

[Yamaha V6]

Have you got access to another PCM?

I've had a very rare occurrence where an engine wasn't running well (but still ran) & it was a bad EEC Box. Double check grounds. Make sure the fuel pump's working. Make sure it's not flooded (cut the injectors out by going WOT while cranking until it catches).

Double check to make sure you didn't swap the MAF & Coil Pack connectors.

 

[projectSHO89]

Make certain you have power to the coil and to the DIS module

Check for a CPS signal.

Those are all you really need to get a spark.

Steve

 

[Yamaha V6]

Sorry, I ignored that he's checking output at the coil vs. "it's not running".

 

[rocket455]

Make certain you have power to the coil and to the DIS module

Check for a CPS signal.

Those are all you really need to get a spark.

Steve

how do i check power to the coil and DIS? also for a cps signal? i have checked all other suggestions but nothing.

this case is so odd though, the engine was running fine then it just died on me with absolutly no spark. then the next day i took off the intake to check everything but did not change one thing. i put the intake back on and it started right up. then on my drive around the block, it did the same thing...*bashes head on wall*

 

[rocket455]

well i have replaced the main engine wire harness, since a while ago, my motor caught on fire and melted alot of the harness which is why i just replaced the fuel injector harness. so while i had some spare time, i replaced the main harness in about 2 hours.