Spark Plugs Not Firing

[Postal_Dave]

I tried to connect a video through Facebook but it won't let me.

 

[Postal_Dave]

I fixed the video.

 

[Josh P]

Strange, like someone turned the ignition off.

 

[Fix4Dirt]

theres also no prior signs like rough idle, it just drops. this is odd i got no idea

 

[Postal_Dave]

I'm so proud of myself for finally getting this engine to run smooth. Now if it will just stay running. LOL
It's a good thing I'm already bald, otherwise I'd be pulling my hair out.

 

[Fix4Dirt]

I wouldve said the pickup coil, know a guy who had that go on his when hot... btu these arent carbbed i do remember that harleys used to have CPS issues when hot, is the wiring looking good to it? wonder if when you got it running cold if you can give it some heat (not too much) and see if that stalls

 

[Postal_Dave]

The most frustrating thing about this is that it still won't start. It stalled at 9:45am est and it's now 4:45 and it still won't start. It's acting like it refuses to run more than once a day. It would be easier to chase the problem if it would start up a little more often.

Tomorrow I'll see if it starts then turn it off before it gets warm. I'll see if it will restart after that.

Right now I'm looking to replace the camshaft and crankshaft sensors because those seem to be the most likely suspects.
Can anybody show me where the camshaft sensor is? I lost my Haynes manual yesterday. It seems to have sprouted legs and walked off.

 

[Fix4Dirt]

on my sohc it was on the valve cover by the fill cap, but on the ohv i want to say its betwen the heads near the firewall. and " it seems to have sprouted legs and walked off" i cant say how much that made me chuckle, im not sure why... everything seems to leave when i need it... that socket that ive never found the day before a job, the wire snipper that i lost before an electrical job,, only to find it days later under the seat... list goes on!

 

[Josh P]

Camshaft sensor is at the rear center of the block near the firewall.

 

[Postal_Dave]

Well, lots of wrenching in my future. I'll start with those two sensors and then report back on whether or not they work. Thanks for all your help guys.
Dave

 

[CDW6212R]

Does the OHV 4.0 have a TFI module like older Fords? Those were an issue to watch for back in the 80's models, they would sometimes act up only when very hot. The TFI could fail completely, or just rough at random times, or shut down at some time when it gets hot. Changing them was the answer, but some people went farther and relocated them. Ford stopped using those many years later, but like everything, changes didn't happen at the same time for all models.

 

[Josh P]

Does the OHV 4.0 have a TFI module like older Fords? Those were an issue to watch for back in the 80's models, they would sometimes act up only when very hot. The TFI could fail completely, or just rough at random times, or shut down at some time when it gets hot. Changing them was the answer, but some people went farther and relocated them. Ford stopped using those many years later, but like everything, changes didn't happen at the same time for all models.

No, this is edis, same as the 5.0L. The symptoms here are similar to a failed TFI, seems like hot electronics failing to run the engine.

 

[1998Exp]

The most frustrating thing about this is that it still won't start. It stalled at 9:45am est and it's now 4:45 and it still won't start. It's acting like it refuses to run more than once a day. It would be easier to chase the problem if it would start up a little more often.

Tomorrow I'll see if it starts then turn it off before it gets warm. I'll see if it will restart after that.

Right now I'm looking to replace the camshaft and crankshaft sensors because those seem to be the most likely suspects.
Can anybody show me where the camshaft sensor is? I lost my Haynes manual yesterday. It seems to have sprouted legs and walked off.

You confirmed that when it refuses to start there is no ignition on any cylinder, right? So unless the '96 is somehow radically different from later models, there is no point in replacing the camshaft position sensor, because that one only affects the injector timing and has nothing to do with ignition. Also, quite unlikely that engine heat affects the ECM because it sits on the cabin side of the firewall. I would start with the crankshaft position sensor and/or its wiring.

 

[Lee's Automotive]

on my sohc it was on the valve cover by the fill cap, but on the ohv i want to say its betwen the heads near the firewall. and " it seems to have sprouted legs and walked off" i cant say how much that made me chuckle, im not sure why... everything seems to leave when i need it... that socket that ive never found the day before a job, the wire snipper that i lost before an electrical job,, only to find it days later under the seat... list goes on!

I'm sure my 10MM socket has legs it always walks off when I need it

 

[Turdle]

Try a new pcm relay. Check the socket it plugs in to for discoloration

 

[Fix4Dirt]

I'm sure my 10MM socket has legs it always walks off when I need it

indeed! it just seems like it walks away, and then i find it somewhere im dang sure i didnt put it!

 

[Runnin'OnEmpty]

Try a new pcm relay. Check the socket it plugs in to for discoloration

Good call.
This is something that doesn't set a code.

Many relays can be swapped around in the relay box, such as A/C etc.

 

[Postal_Dave]

UPDATE: I've replaced the Camshaft Position Sensor, the Crankshaft Position Sensor, and the Ignition Coil Pack. I've checked all related fuses and the PCM Relay.
Tried to start it and, once again, no spark. It just turns over.
I connected an old spark plug and wire to the coil pack and videoed it while cranking. It only sparks when I quit cranking it.

My trick of leaving the car unplugged from the battery for an extended period and letting it cool no longer works.
I've already replaced the EGR, O2 sensor, spark plugs and wires.
Here are the codes from the cheap Walmart scanner I bought. I have no idea what they mean. Can anybody translate these codes and tell me why I only get spark when I quit cranking the engine?
Thanks Guys,
Dave

 

[Fix4Dirt]

not an expert, but i dont think you have codes. your dtc (drag trouble code) count is 0, and the first 2 images are your fuel trims, which is the adjustment to maintain the desired afr. short term is quick adjustment made, long is almost like an average of the changes made so to speak. load pct iirc is the precent load calculated by the computer, rpm is rpm, VSS is vehicle speed sensor, should be 0 cause youre not moving, spark adv is the timing of the spark plug firing iirc, and thats ajusted based on load/rpm... i think... IAT is intake air temp, shoudl be close to ambient temp if the motor is room temp. MAF is the amount of air the maf sensor senses going by it. TP aint toilet paper, unfortunately, its throttle position. i forget if thats on the pedal side it measures it, i assume it measures how much its open from the TB. afaik, and not too sure. o2sloc is the location of the o2s, like bank 1, forgetting what the S means. the other o2 ones are the voltage readings form o2 afaik. the other ones are related to fuel trims on that pic. (the shrtft ones) afaik thats short term furl trims again. and obdsup is i assume if its obd2 or obd1. the next pic is of the emissions readiness, which means the vehicle goes thru some tests to ensure its running at its peak and is ready for emission testing, and that if theres a code it wouldve been tripped (to keep people from clearing dtcs outside the smog place), after driving a bit, those should eventually turn to check marks as it goes thru its tests. theres a procedure for it techinically, but just driving around is good enough imo. the pd dtc is pendng diagnostic codes. luckily youve got 0 codes, so looks good. diid you just clear em? i doubt it would throw a code this early, considering battery was disconnected etc, so that cleared codes. so imo its too early to check codes, gonna need some driving to get any help from the scanner imo. that being said, does yours read enhanced dtcs? sorry this was so wordy

 

[Josh P]

Check for voltage on the red wire going to the ignition coil pack. It should be battery voltage with the key in the run position. Crank the engine, (try to start) and check what the voltage is. It should be the same as in the run position.