Tach Flutter=Ignition Problems

Sy769

Donating Member
Yippee got the dreaded tach flutter during acceleration, cruise.
The day before the 02 Nats- new conrad cap,taylor wires,NGK UR6's gapped at .035, Prior to this I was getting 12 Deg retard. Now I'm down to 2-4 with a occcasional 8 deg. typically so the stuff did help but didn't cure the flutter. :-?
Also the ignition module was replaced at 01 Nats

Here are my thoughts:
Weak coil possibly?
Might tighten the plug gap up some. Anyone have a idea on how much to start with.

Another glitch I am having is Datamaster loses it's link right after go full throttle but works fine otherwise :-? Always worked fine once I got the ALDL timing right.


Stock chip, turbo
Walbro 255
AFPR
 

smeagol

Active member
My guess - wire not on good, bad wire, plug cracked...



IMO, tach flutter is almost always wire related
 

Sy769

Donating Member
Well I didn't find anything obvious yet. All plugs good, .035 gap None of the wires are burnt,they are only a few weeks old. Guess I 'll get out the ohm meter and measure them. Seems like someone had a ohms per foot number that I can check them against.

Drove it some today and ignition is definitely breaking up under boost.
If the wires test good might put in a new coil since it is the only thing left besides the Distributor that is not new. Any one have any problems with the aftermarket high output coils ? I have a msd 6A but I am not putting it on until I get this sorted out.
 

Typhoon #1133

New member
you truck sound just like mine. at the nats my guages went crazy!!! also my datamaster program would lock up sometimes at wot, when i let of the gas it would start recording again. my volts been running low so i chagned my alternator and it seemed to help with the guage flutter. i have new plugs, cap and rotor and my knock is still around 9 max at times.
 

Sy769

Donating Member
I dunno,when I took my module out a year ago I put a new one in maybe somethin to check on Still haven't pulled all the wires and checked them with a ohm meter.It is breaking up bad under boost now. But that's on hold considering I am in a UHAUL truck with the Sy on a trailer half-way to Dallas.
 

Stangbeater

How bout it?
What kind of wires are you using? I had tach. issues when I used the Holly wires with the metal boot shields on them. I still don't know why anyone would put metal boots on plug wires.
 

Sy769

Donating Member
smeagol said:
My guess - wire not on good, bad wire, plug cracked...



IMO, tach flutter is almost always wire related

Be honest BG that wasn't a guess was it? You looked in your syty crystal ball :lol: 8)


Well I finally got time to work on the truck. pulled all the plugs good coloring all look the same. Hmm start checking plug wires with the ohm meter. Found one with inf. resistance. It had no continuity at all. I guess the spark was jumping the gap so it fired under "granny" driving but under boost it flamed out. These are Taylors that were put on 48hrs before the NATs and have about 2500 miles on them. This wire had no external
damage
Put on a cheapy I had laying around. It runs gooder very gooder :D
 
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