If the tach filter is unplugged, would that make the engine not run? I unplugged the Tach filter, and the engine wouldn't start up. It turned over. I plugged it back in, the engine STILL won't start up. Any ideas? All firing system EXCEPT pickup coil is brand new. Was running fine with all new equipment this AM.

jw

Tach filter shouldn't cause a no-start condition. I would check to make sure you have fire to the plugs. I've heard how a malfunctioning tach filter can cause an ignition module to fail, but I personally have never experienced such a thing happening to me. If the pickup coil has failed that can cause a no-start situation and is easily tested by checking resistance between the two points on the plug going into the module. If its good you should get a low resistance reading, if it's bad, it'll read infinite or very high.

Wwhere is tach filter located and how does one turn it off?

David, the tach filter is located right beside the distributor on V6 engines. This is what it looks like:

Courtesy of Rodney Dickman

If your tach is acting funny and you think this is the problem, all you do is unplug the wires.

Mac... The tach filter will not cause the engine not to run. I haven't had mine plugged up in months. Like Blake said above, I would check the module and see if it was somehow blown. I have no proof but in my case, I think my bad tach filter did blow my module. I just replaced the module and left the tach sensor unplugged.

On a side note: I did get one of Rodney's aftermarket tach filters. One thing you want to do with these is make sure you have them held in place firmly. Mine got down on the exhaust and burned it enough to cause a short. Luckily, I saw the tach acting up and stopped and unplugged the filter before it damaged the module.

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got to ask the obvious question

when you replaced the pickup coil, I assume you had to remove the distributor

how did you reset the timing, if the car wont start? if the timing is waaaaaay off, the car will not start.

[This message has been edited by Ken Wittlief (edited 07-25-2003).]

A bad tach filter can blow an ignition module. It can also fry the ignition and pickup coils.

A bad filter can short partly or completely to ground and keep power flowing thru the coil when it shouldn't. This results in weak or no spark.

If it is a "loose" short it can also screw with timing...

By loose I DO NOT mean the mount... Tho that isn't good either. I mean the gutts of the filter are loose and shorting.

A "Loose" filter can cause coil firing when it shouldn't. It is the same effect as if you took the one filter wire and taped the end against the engine block. It's not shorted all the time, just when you tap it...

A "loose" filter/short is a bad thing in a couple ways... It can cause miss/skip problems. Worse it can have the same result as pulling the coil secondary wire... The coil may actually fire when the distributor isn't lined up. The spark energy still has to go someplace so it either arcs thru ignition parts or feeds back and spikes the module. Either one can fry the whole ignition system.

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Nobody loves me. Everybody hates me. Guess I'll just go eat worms.

quote Originally posted by Ken Wittlief: got to ask the obvious question when you replaced the pickup coil, I assume you had to remove the distributor how did you reset the timing, if the car wont start? if the timing is waaaaaay off, the car will not start. [This message has been edited by Ken Wittlief (edited 07-25-2003).]

Well here is the situation. It was the pickup coil. It looked like the original one in the vehicle was still there all these years.

jw