97 Ford 7.5 engine no spark

[jcross312]

Hey yall, I have a 97 ford F53 chasis motorhome with the 7.5 litre gas engine. Only has 35k miles on it and has always ran fine. Up until a couple months ago after sitting for 2 months engine would not crank. I've determined that the ignition is not firing and have replaced coil and ignition control module, but it still is not firing. Anybody got any good advice? Thanks in advance.

[Rene T]

Hey yall, I have a 97 ford F53 chasis motorhome with the 7.5 litre gas engine. Only has 35k miles on it and has always ran fine. Up until a couple months ago after sitting for 2 months engine would not crank. I've determined that the ignition is not firing and have replaced coil and ignition control module, but it still is not firing. Anybody got any good advice? Thanks in advance.

You said it would not crank then you said it is not firing. Not cranking to means it's not turning over.

[TonyDtorch]

Hey yall, I have a 97 ford F53 chasis motorhome with the 7.5 litre gas engine. Only has 35k miles on it and has always ran fine. Up until a couple months ago after sitting for 2 months engine would not crank. I've determined that the ignition is not firing and have replaced coil and ignition control module, but it still is not firing. Anybody got any good advice? Thanks in advance.

there should be a crank position sensor somewhere.  when they go bad there is no signal to the coil.

If that doesn't fix it then it may in the ECU.

[jcross312]

It's turning over but no spark.

[jcross312]

Thanks Tony, I'll check that

[rls7201]

NO crank position sensor. All spark control is generated in the distributor, then sent to the TFI on the fire wall and then to the coil.
There is an ignition fuse in the big plastic box under the hood.

[jubileee]

Crank position sensor (equivalent) is built into distributor. I would pull distributor cap and make sure distributor is rotating. Sometimes roll pin on distributor gear will shear for no apparent reason. Easy fix. If it’s rotating, you can either load the parts cannon ( coil, distributor, ecm, and ect) or do your detective work. I have owned 7 or 8 fi 460 fords and still own 3. Sudden no spark has nearly alway been distributor related, though one time it was the ecm. Also, one time it was the single 12 gauge wire ( on motorhome) on positive battery post wasn’t making contact

[jcross312]

Thanks rls and jubilee, I've already checked all the fuses and they are good. Also, I'm getting power to the coil (both wires) but no pulse when I turn the engine over. I got a new distributor for $80 and threw at it. Still nothing. So I've spent about $200 on parts to no avail and also ordeed an oem ignition module today for $100 from ford dealership. Have tried a new aftermarket one already. Also tested coil and it is testing good, and have replaced it also. It was only $25 so figured I'd try it anyway. About the only thing left is the ecm. It's jammed up into part of the fire wall, still trying to figure out how to get it out of there. I'm gonna research more testing methods to try to pinpoint the problem, but really only other part to replace is the ecm. It will probably be a loose wire or something after all of this. Smh.

[jubileee]

You can pull the jumper on the “spout” connector and isolate the ignition control module. You have to do this when timing engine. Connector is located right along with diagnostic port on separate wire. Google. little gray doo Hickey. Just pull it out and you bypass module. Never had a problem with after market modules or junk yard ones for that matter. Last ecm I got from Autozone  for 460 was $200 with core. $290 without core I think. I kept core, opened up, found blown cap, soldered in new one (40 cents or so) and put back in vehicle. Still running there in 92 Bounder. 6-7 yrs. Put the Autozone one in the spare parts compartment.

[jcross312]

You can pull the jumper on the “spout” connector and isolate the ignition control module. You have to do this when timing engine. Connector is located right along with diagnostic port on separate wire. Google. little gray doo Hickey. Just pull it out and you bypass module. Never had a problem with after market modules or junk yard ones for that matter. Last ecm I got from Autozone  for 460 was $200 with core. $290 without core I think. I kept core, opened up, found blown cap, soldered in new one (40 cents or so) and put back in vehicle. Still running there in 92 Bounder. 6-7 yrs. Put the Autozone one in the spare parts compartment.

Ok, yes, I've seen that spout connector. Mine is right beside the icm in front of the firewall. I will try unplugging it tomorrow. When your ecm went out did it no longer fire/spark?

[jubileee]

Ok, yes, I've seen that spout connector. Mine is right beside the icm in front of the firewall. I will try unplugging it tomorrow. When your ecm went out did it no longer fire/spark?

I was going down the road and it was like I shut the key off. Last thing I expected was ecm. Since then, on other older vehicles, I’ve learned to open up ecm and look for blown capacitor when all else seems to fail. I’ve repaired the one on the Bounder I mentioned ,a 90 astro, and a 92 Geo tracker (toad).
I’m no electrical wizard by any means. I know how to hold a soldering iron and a solder sucker and that’s about it.

[jcross312]

You can pull the jumper on the “spout” connector and isolate the ignition control module. You have to do this when timing engine. Connector is located right along with diagnostic port on separate wire. Google. little gray doo Hickey. Just pull it out and you bypass module. Never had a problem with after market modules or junk yard ones for that matter. Last ecm I got from Autozone  for 460 was $200 with core. $290 without core I think. I kept core, opened up, found blown cap, soldered in new one (40 cents or so) and put back in vehicle. Still running there in 92 Bounder. 6-7 yrs. Put the Autozone one in the spare parts compartment.

Jubilee, thanks so much for the spout connector advice! I finally got around to trying that this evening and the coil is now firing again! However, still couldn't get engine to start. It did pop a couple of times like it was trying to. I replaced distributor, but tried to just "eyeball" it back in same timing. Not sure how exact the distributor placement has to be. Was gonna get it to fire and then worry about timing. Could you elaborate on the spout connector and what my problem appears to be. Is it a bad icm since you said that bypasses the icm. Thanks so much for the advice. It's really helped me out with this beast.

[jubileee]

Normally yes, it indicates a bad icm. It’s confusing because you said you replaced the icm Was it black in color? Engine needs to be timed precisely with spout jumper removed and engine warm. 10 degrees BTC. ( or wherever emissions sticker says if it has one) Also, not preaching here, but I would trace and number each sparkplug wire and number cap terminals in firing order if you didn’t do so when you replaced distributor. Good Luck.

[TonyDtorch]

it might be time to put a timing gun on the #1 spark plug wire and see if it is firing on, or anywhere near the timing mark where it's supposed to be.

 It is possible you were off one tooth on the rotor when you put the distributor back down in.

[jcross312]

Well, worked on it more today and motor had a kick back condition which indicated over advanced timing. Retarded the timing some and finally got the beast to crank. Let it run for awhile and it was a good feeling listening to the engine running for the first time in months. Finally...the breakthrough i was looking for!! Shut it off and tried to crank it again and had trouble starting the engine. So after doing some head scratching decided to plug the spout connector back in to see if it would spark with it connected. Lo and behold the ignition fired up and so did the engine. Success is mine at last! Lol. Have absolutely NO idea what was going on, but it is working again. Maybe a bad connection somewhere, not sure. Took her down the road and pinging was pretty pronounced, so retarded the ignition some more at distributor and pinging went away. Running good again. May fiddle with dist. timing some more but For Now all is well again. Mustve been a gremlin in there somewhere. Probably didnt need to replace any of the parts i did, but oh well, still cheaper than a shop bill and learned about this engine in the process.