warthogcrewchief

I was driving home last week on the Interstate, while passing I heard a "pop" from up front (sounded a little like a backfire in the intake). The oil press and tach both went to zero so I immediately knew I had an engine problem. Could not restart after that point.

I have fuel getting through the system (I hope so as the fuel pump that's less than a month old!). I verified I had no spark at the spark plug.

After looking over the wires, I found that the coil wire (coil to distr.) had the outer insulation burned through. I changed out the entire wire set, and verified the wires are in the proper firing order.

I tested the coil. The primary was difficult to get an accurate reading as it was fluctuating, but did eventually get .6 ohms, which is just out of spec. The secondary was good. I changed the coil out due to it testing just out of spec.

I have spark from the coil wire, but when I connect it to the distributor, the plugs don't get spark. I verified the rotor was turning when the engine turns, and it does.

I replaced the rotor and the cap...still no spark!

I removed the ICM and had it tested at autozone on their Wells tester. It passed. The guy working there swears up and down that the ICM is bad DESPITE it testing good.

When feeling how the distributor felt, the rotor can freely turn almost an 1/8th of a turn Counter-Clockwise. It stops at that point, but has that "slop" or "play".

Do you guys think that this is a distributor or a ICM? Those are about the only two items left to change out on the ignition system.

A faulty cam position sensor would not cause a no-spark issue. A faulty crank position sensor would prevent fuel and spark from occurring, but I have spark (up to the coil wire) and fuel.

Highly doubt it's related, but while cranking, I occasionally heard some nasty metal noises, which I have since determined to be the starter (replaced less than a month ago). It only occasionally does it, and the battery seems to drain fairly quickly when cranking the engine. There were no shims with the original starter, so I doubt it's the starter alignment. I'll place the battery on a Battery Tender to recharge the battery and the engine cranks strong when the battery is full.

I'm out of ideas and I don't want to throw any unnecessary parts at the truck. Is there something I'm missing? Any ideas?

Thanks in advance!

73shark

I wonder if you should pull the distributer to see if it might have shed a tooth on the gear.

in2pro

Are you certain the cap and rotor are making contact at the center electrode?
if not you will never get spark to the plugs... you way want to pull the distributor and check for excess ware that could have caused the shaft to drop or misalignment.
Check the rotor for rotational marks..

warthogcrewchief

I didn't see any unusual marks on the rotor or the cap. I thought it strange that the rotor (and distributor shaft) would have about a 45 degree area of play. I know the distributor is supposed to be rotated 45 degrees back from No. 1 TDC prior to install so that the gears will rotate and mesh into the correct position.

I could have a messed up tooth, but the rotor seems to be moving properly.

I'm going to replace the distributor this evening...as that is the only thing that I have not replaced.

Gonna go find TDC and re-evaluate the position of the rotor based on the alignment mark I painted under the No. 1 wire port.

73shark

45* of slop is way too much. No telling what the timing is w/ that much movement.

warthogcrewchief

Found the culprit. Charging the battery right now and will test/start it after I charge up the battery.

The gear/cog on the distributor had about half of its teeth sheared off. Doesn't surprise me considering it occurred at 70 MPH. So, as soon as I get it running, it gets an oil change!

As with everything on the interweb, if there wasn't photos, it didn't happen.

73shark

Glad you found it.

warthogcrewchief

Me too! Only problem was I spent WAY too much money and time on this fix. The first thing I did was check the wires, and the coil wire was toast, so I changed out the whole set as they needed to be done ($45). I tested the coil and the primary tested just barely out of the operating range on the primary side, so I changed it out ($30). I saw the rotor was turning, but was not getting spark past the the distributor, so I changed the rotor/cap ($50). At this point, the only two things left that could be bad was the distributor or the ICM. Despite the ICM testing good on the AutoZone Wells tester, I buckled and replaced that. The cocky autozone manager swore up and down that it would be an ICM that would fix it ($80). So, after that didn't fix it, I spent $160 on a new distributor which comes with a new rotor and cap!!! So, about $300 later, it should be fixed. I'll be extremely pissed if the slight miss at idle doesn't disappear! lol

73shark

Look at the bright side, you got a brand new ignition system except for plugs.

warthogcrewchief

LOL! I replaced the plugs less than six months ago, so it is a new ignition system!

The first time I installed it, I had it off 180*. It backfired a little. Fixed it, took a few times to get it on the right tooth, but now it's running great. I have a CEL on, but most likely due to the 180* off/backfire condition. I'll take it to a friend tomorrow who has an OBD II tool to clear the code.

It's running smooth and quiet!