Tb IV intermittent spark ?$#???

Scott06

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Now I am getting 12v at coil +, and 11.84 coming out of module via red/wht wire, followed by 8.62 at the red/wht going into the distributor...now where do I go? Still no spark coming out of coil tower?
Follow the service bulletin he posted I circled where you are at in it - by striking the white and green lead to ground you are simulating what the sensor in the distributor does to get the coil to fire. If it does fire at coil the sensor is bad if it does not fire follow to testing for bad coil and then bad module.

You just need to follow the troubleshooting guide.
 

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mrzooom

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Yes, I did and this morning I can't get any spark out of the coil. I get red/wht wire showing 11.84 from the ignition module, in fact I'm getting like 8. 6 or something from grn/wht out of dizzy...???
I spent the morning striking the grn/wht to engine ground...no effect...
 

Scott06

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Yes, I did and this morning I can't get any spark out of the coil. I get red/wht wire showing 11.84 from the ignition module, in fact I'm getting like 8. 6 or something from grn/wht out of dizzy...???
I spent the morning striking the grn/wht to engine ground...no effect...
If it is a good ground then that means the sensor is bad. Not surprising since it went scuba diving ...

Would recommend getting an OEM sensor vs the aftermarkets ones. this is an OEM quicksilver from the quicksilver store on Amazon

 

mrzooom

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You know what? Yeah my new sensor is aftermarket. So first thing is I gotta get a new OEM. I'll report back...
 

Scott06

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You know what? Yeah my new sensor is aftermarket. So first thing is I gotta get a new OEM. I'll report back...
Wait sorry i misread the tb trouble shooting, if you do not get spark striking the green white its says to try new coil then replace module in that order… do u have a spare coil to try ?
 

04fxdwgi25

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are your coils the 12v ones or the ones that require an external ballast (reduced voltage)?

My TB5 is a 12v coil
 

mrzooom

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Yes, went to an ACCEL HEI. Finally as that was what was on it before all of this...but I'm gonna replace a new OEM sensor...
 

mrzooom

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You know, the one I replaced with all said "internal resistor" but my understanding is it calls for one that states "external" resistor on the body so I got the ACCEL...
 

mrzooom

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Yes, I bought an Excel HEI. But maybe that's not the right coil?
 

mrzooom

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So then, what coil should I be using? MercMarine/"internal resistor required" Or HEI/"external resistor required"?
 

alldodge

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Any internal resistor coil, and from what I've read it's not the coil

Did you run through the troubleshooting post 41?
 

mrzooom

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Any internal resistor coil, and from what I've read it's not the coil

Did you run through the troubleshooting post 41?
Yes I have...asked and answered, but alldodge, once I install new OEM sensor and regular coil...hopefully will have spark...unless ignition amplifier/module/harness is bad...right? I think.
Thank you for your time, btw...
 

alldodge

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Everyone says OEM only yet last week there was a guy who installed OEM and had no spark. He bought a cheap amazon knock off for dumps and giggles and it worked.

So was it something else, bad connection, other, I have no idea but only reading what was posted. I mentioned to take it back to dealer he bought it from but have not heard back
 
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