HELP 1991 SHO + No Spark STRANDED

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FiftySiX

91 SHO +
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Hey guys. Bought a 1991 SHO Plus 103k miles. Been running fine. Massive oil leak lead to replacing the front main. Cleaned area with throttle body cleaner and yes I did get some on the CPS but was cautious as I could be.
Re assembled and I had a whine front the belt side. Possibly a belt too tight? Drove 300 miles and on the way I started getting extreme studder in and out. Seemed worse at top of pedal. Popping and very hard thrusts from loss of power. Tachometer was going haywire during the outbursts of skipping/sputtering. Pulled into oreileys changed bands around the rear plenom above timing belt thinking I had a vacuum problem. Didn't notice much stalling afterwards, tho it did get 30 minutes to cool off while installing the bands. Drove to my friends house I'm vacationing with this week and decided to lossen the belts to eliminate the supercharger like whine. In an attempt to ensure the timing tensioner couldn't be over taught, I removed the timing belt and my cam gears shifted. I also moved around the crank loosening the harmonic balancer bolt. I've been told these are non interference engines though? I aligned the cams with the markers on the top of the rear timing housing and the crank with the circle on the timing gear with the oil pump housing guide. Assembled the belt, tightened everything up. Now I have no start situation. I've done the self diagnosis sysytem KOEO but I get a code pattern I'm not sure I'm reading properly as it just blinks 1's no fast blinks as if to indiindicate a 2 or 3 just 1's. Tested for spark via a spark plug and a screwdriver no spark. Limited tools. I had a 2.3 cougar die on me once like this and it was the ICM. But the cougar never studdered. So my question is what am I looking at here? Crankshaft position sensor, camshaft position sensor, or Ignition Control Module? How do I test? Parts aren't cheap. HELP!!
 

rubydist

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typical symptoms of bad crank sensor, but a sick cam sensor can cause issues too. the fact that there is no spark leans toward either crank sensor or dis module.

the '111' code that you get is the all-clear, I'm guessing you had the battery disconnected when you re-installed the belts. next time, pull codes before you disconnect battery, since disconnecting battery erases any codes.

but, before you go any further, double-check all the grounds to the engine. a missing ground from the intake manifold will also result in the symptoms you are now experiencing - the dis will not work if not grounded and it grounds to the intake manifold which means the intake must be grounded to the chassis.
 

FiftySiX

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Checked the ground wire, everything is fine. CEL light never came on during the bucking and skipping though. In fact the CEL light has only came on a few times buy has never remained on. Just emission situational temporary codes. And that was once.
 

FiftySiX

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Issue still exists. Not looking forward to just tossing money at it. Any tests that might help me?
 

Devin

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CKS. I had this problem when my water pump pulley chewed through one of the wires. Car would run fine, the CEL would flash and then I couldn't keep constant acceleration. It became impossible to even maintain speed. Since you just did your front main that means you'd have to remove and reinstall the CKS.
 

FiftySiX

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Cks? And like I said. It only started having trouble yesterday. Parked it and adjusted all belts again then no spark. And I didn't remove the timing gear from the crank this time. I was very detailed in what happened too read carefully. 15+ years Chevy mechanic. Still new with ford or efi period
 

FiftySiX

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And the CEL didn't come on yesterday at all. Coil pack maube? Just found a Motorcraft sticker on it. Guessing it's 23 years old.
 

Devin

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CKS: crankshaft position sensor. Coil pack failures are somewhat uncommon. Also, there are three coils so chances are not all three died at the same time.
 

FiftySiX

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Turning over the engine I received a rpm readout. So the CKs sent the tach the signal. The ignition module caused the no spark situation. Trace your input and output signal peripherals and you'll find RPM under the crank sensor. :) Love my $800 yamaha. I refuse to shame it with the name ford. Nor will I capitalize the f. Lol
 

sperold

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What kind of diagnostic tool did you use to get the RPM signal from the crank sensor?
Very good information to have.
Thanks
 

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