No Power to Coil
 

Hi Guys -

1994 NAS D90 - pretty much stock and freshly rebuilt. By rebuilt, I mean almost totally rebuilt... 3.9L, R380, LT230, new galvanized frame, new dizzy, new ignition barrel, new ignition amplifier, new alternator, new starter, all nice clean grounds, repaint, all new suspension bushings, rebuilt front and rear axles... the list goes on and on. Got her back on the road a few weeks ago and drove about 1k miles since.

Last Saturday drove through a massive storm for about 1 1/2 hours. Water leaked in the front vents and windows/doors (no surprise). Made it home just fine and the next morning she fired right up and I drove for about 20-30 miles. No problem. A bit later, I went to get gas and after filling up I turned the key and the fuel pump didn't prime. I pushed her to a corner of the gas station and came back the next day with a new relay for the fuel pump (and one for the main relay as well). Fired right up :) Drove around for a day and then she started running rough and the CEL came on. Threw a 45/44 code. I had replaced the O2 sensors about 3K miles ago and the exhaust system is new. As I was pulling into the garage to begin some further investigation, she died and won't start. Cranks just fine, fuel pump primes. I checked for spark and nothing at the coil. Checked battery voltage - 12.55V. Checked power to the + side of the coil and it reads .3V. Negative side is zero. Sounded to me like an ignition switch failure so I swapped in a new ignition switch and no change.

Main ignition fuse in the engine bay is good and there is battery power there. All fuses in the cabin fuse panel are good as well. I have started continuity checking of the ECU but thought someone might have a few ideas I could try. I have scoured the forum but can't seem to find a relevant thread.

Thanks in advance!

Have you got the 14CUX diagnosis PDF. It walks through all the steps.

Definitely cycle the fuel shut off. Its the plunger looking thing at the top/behind the fuse box.

try an overlay power wire from battery, if this works, then trace your ignition wire circuit for breaks due to corrosion, short to ground, defective ignition relay.
if it does not work, then begin to suspect ground concern or defective coil, it is not unheard of a new coil to fail. since you state you have done a rebuilt, it is possible grounds are loose or poor thus causing you numerous electrical gremlins.

Thanks Jason - I think I have the one you are referencing (the one I have is and electrical troubleshooting manual for a 1993 Range Rover but for the 14CUX MFI) and have been walking through the steps. I'm about halfway through and the only thing so far is that test 2C is supposed to read battery voltage (about 12.5V) but reads around 10V. Not sure if that is significant or not.

------ Follow up post added September 23rd, 2016 10:06 PM ------

Thanks Bill - I forgot to mention that I did that in my initial attempts to resolve the issue. I also pulled the "chicklet" and measured the resistance. It was spot on where it was supposed to be. Thanks a bunch for the input though.

Hi Carlos - good thoughts. If I don't have power to the + side of the coil, I wouldn't think the coil was the issue. I guess I should try to measure the voltage from the back of the ignition switch with the key in the II position. I guess it should read battery voltage?? I need to check and see if I have a wiring schematic to show how the wiring runs from the ignition to the coil. Not sure where a short would be. Seems so odd that it started and ran great for 1k miles and then had the problem.

I'd run a jumper like Carlos suggested. I've had enough new out of the package parts failures that I never rule them out. Water through the vents may very well have gotten in things.

One year on Portsmouth Island my son's 110 wouldn't start when it was time to roll on the ferry. We got it going and once home tore into it to find the starter relay was full of rain water.