TFIDFIS gurus I need some help.
12-05-12, 03:44 PM
#1
TFIDFIS gurus I need some help.
I have had TFIDFIS since July '11. I had used summit racing brand coils. The car idled so smooth you wouldn't think it was a rotary.The high rpm hesitation I was having turned out to be 2 of the coils going bad. I had one completely go out. After a friend put a timing light on the plugs the problem was discovered.Turns out summit only warranties their coils for 3 months. so I went to advance and ordered 3 new msd coils. get everything hooked back up pull the choke crank the car and it fires right up and is running smooooth. A minute later I start hearing this tic,tic,tic,tic,tic and the engine starts running bad. I feel the side of the dizzy and wow, I'm getting hit by voltage at the base. Now the trailing is the only thing going through the dizzy. Inside there is a little metal cap that separates the spark from the magnetic pickup. I silicone a piece of plastic to the top and wrap electrical tape around the sides. fire it up and it's smooth for a minute then tic,tic,tic,tic...arcing in the dizzy again to the base!!!! I don't get it. Any ideas???I guess I'm going to have to put the trailing on direct fire if I can't fix it.
Last edited by rare70cat; 12-05-12 at 03:44 PM. Reason: spelling
12-05-12, 04:02 PM
#2
Um, you technically have DLIDFIS. Use that in your searches. You might have better luck.
As for the arcing problem in the dizzy cap, try moving the trailing plug wires to the other circuit. I always recommend to move them from the stock trailing position to the leading one so there is one less gap to jump (the carbon button). If that doesn't temporarily solve your problem, you need a new dizzy cap and rotor. Otherwise it may work ok for a while but you still should get a new cap and rotor.
So out of curiosity, what parts are you using? GM HEI ignition modules/ignitors? Bosch? Stock J-109? Other?
How are you feeding the leading pickup signal from the dizzy over to your leading ignitors? Where are your leading ignitors located in the engine bay?
What have you done in total on your trailing ignition? In other words, just how stock is it still? It may shed some light on your problem.
As for the arcing problem in the dizzy cap, try moving the trailing plug wires to the other circuit. I always recommend to move them from the stock trailing position to the leading one so there is one less gap to jump (the carbon button). If that doesn't temporarily solve your problem, you need a new dizzy cap and rotor. Otherwise it may work ok for a while but you still should get a new cap and rotor.
So out of curiosity, what parts are you using? GM HEI ignition modules/ignitors? Bosch? Stock J-109? Other?
How are you feeding the leading pickup signal from the dizzy over to your leading ignitors? Where are your leading ignitors located in the engine bay?
What have you done in total on your trailing ignition? In other words, just how stock is it still? It may shed some light on your problem.
12-05-12, 05:24 PM
#3
I'm using 3 MSD #8207 coils and 3 GM 4 pin HEI modules. I replaced the cap and tried a spare rotor button I had. Same problem. I made the stock ignitors pass thrus by soldering the jumpers for both leading and later trailing. I was using the stock ignitor with a summit racing coil for the trailing then the stock ignitor went out so I hooked up another Gm HEi module for trailing. For the trailing, stock ignitor is now pass thru which goes to an HEI module, one MSD coil feeds the dizzy cap to the leading side (as you mentioned) and then plug wires from L1 & L2 to T1 & T2 plugs. I had a problem with heat on the little piece of aluminum bar that I put the modules on so I bought a piece of angled aluminum and cut slots on one side to create heat sink fins. I have that mounted on a shock tower mount bolt. When I added the third hei module I made a smaller heat sink mount from the same angled aluminum and mounted it above the bracket that has all the relays underneath near the brake booster. I also have new MSD super conductor wires. 50 ohms a foot spiral wound copper. Before I used summit racing wires equivalent to the msd super conductor. Half the price. I have an '81 engine in a '84 car. I have the three coils mounted in aluminum bar and mounted to the driver shock tower.There were 2 factory threaded holes one above the other that are #10 so I used those holes for mounting the three coils. It's pretty clean.
12-05-12, 05:29 PM
#4
Oh, I did try moving the trailing wires from the leading position back to the original trailing position and still had the same problem so I moved them back to leading because like you mentioned there is greater distance between terminals
12-05-12, 05:37 PM
#5
That all sounds great, like classic DLIDFIS. I wonder if the cap and rotor are faulty? Like bad plastic or something allowing a path for voltage to leak to the dizzy housing and ground out?
Another thing to look at would be inside all the connection points of the high voltage wires. Make sure you're not getting high levels of resistance. PercentSevenC's car would misfire a lot and I discovered three corroded terminals - two spark plugs and one bad coil terminal. I had to throw the coil in the trash because it was too far gone. The plug ends can be easily cleaned up on a wire wheel. His wires were not gripping the brass and aluminum connections tightly enough and all that arcing produced ionized gas which corroded the metal as there was no way to vent it.
Another thing to look at would be inside all the connection points of the high voltage wires. Make sure you're not getting high levels of resistance. PercentSevenC's car would misfire a lot and I discovered three corroded terminals - two spark plugs and one bad coil terminal. I had to throw the coil in the trash because it was too far gone. The plug ends can be easily cleaned up on a wire wheel. His wires were not gripping the brass and aluminum connections tightly enough and all that arcing produced ionized gas which corroded the metal as there was no way to vent it.
12-05-12, 06:52 PM
#6
I had to make up the the five wire ends for the coil sides and dizzy cap side. MSD gives this cool little device for cutting off the exact amount of insulation without cutting into the conductor and this cool tool for crimping the connections in a vice instead of a crimping tool. I thought I got excellent crimps/connections. I had the original rotor and a spare I kept. I tried both rotors. I can't feel any voltage outside the cap. I only feel it at the base and it's significant! I will hit the the brass terminals for the dizzy side with a fine wire wheel tomorrow. It's just weird. I'll also put a meter on the three wires and check for continuity.Oh and I replaced the plugs with the stock NGK like 2 weeks ago when I was having the high rpm hesitation. Thanks for all your help JEFF20B
12-06-12, 07:56 AM
#7
Waffles - hmmm good
iTrader: (1)
To me it sounds like it could be a grounding issue. I would get a DVM and check to make sure
all the wires have the same and low resistance, especially the trailing wires. Then I would
make sure the ground to the chassis (driver side shock tower) and engine (down at the starter)
bolt is good and solid. Also make sure the battery connection on negative is clean and tight.
Check the resistance of the ground cable. With age they can deteriorate if ever exposed to
the elements.
Just to recap, you get shocked if you touch the base of the dizzy (metal part) and your leading
and trailing are both running rough. Is that about it? The electric charge from the coil will go
to ground via the least resistance.
all the wires have the same and low resistance, especially the trailing wires. Then I would
make sure the ground to the chassis (driver side shock tower) and engine (down at the starter)
bolt is good and solid. Also make sure the battery connection on negative is clean and tight.
Check the resistance of the ground cable. With age they can deteriorate if ever exposed to
the elements.
Just to recap, you get shocked if you touch the base of the dizzy (metal part) and your leading
and trailing are both running rough. Is that about it? The electric charge from the coil will go
to ground via the least resistance.
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12-06-12, 03:11 PM
#8
leading is fine. car pulls nice with just leading just not as hard.car defin. needs trailing and pulls harder with it. yes, i get shocked at base of dizzy by trailing. You can actually hear the arcing. If I pull the plug on the ignitor pass thru arcing stops and cars runs smoother. I know the shock tower ground is still there because its part of the negative cable from the battery. I would have to check the starter side. Going to check out these things mentioned.
12-06-12, 04:58 PM
#9
check grounding with a vom from battery to block was like 0-1 ohm. I had had a slow voltage drain and finally found it. I put my meter on the negative battery post while it was disconnected and put my pos. on the block and had 12v!. I got out my test light, hooked it up to the negative battery post (neg still disc) and it lit. pulled out all the fuses.still lit then I heard like a ticking from the trunk and the test light would flash with the tic. I unplugged my power antenna,which worked, and the test light went out. So i'm pretty sure that was my drain. Checked continuity on new wires. t1 wire 60 ohms,t2 wire 65 ohms and coil wire 70 ohms, Checked cap and rotor. All connections test good. After disconnecting the antenna I hooked everything back up fired up the engine with out the trailing hooked up.let it warm up then hooked up the trailing signal and the arcing still happening. you can feel and hear it at the base of the dizzy. I think I'm just going to buy a 4th coil and 4th hei mod and bypass the cap all together. It's weird.
12-06-12, 07:02 PM
#10
Dragons' Breath
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leading is fine. car pulls nice with just leading just not as hard.car defin. needs trailing and pulls harder with it. yes, i get shocked at base of dizzy by trailing. You can actually hear the arcing. If I pull the plug on the ignitor pass thru arcing stops and cars runs smoother. I know the shock tower ground is still there because its part of the negative cable from the battery. I would have to check the starter side. Going to check out these things mentioned.
Gerald m.
Last edited by gerald m; 12-06-12 at 07:06 PM.
12-07-12, 07:09 PM
#11
I figured it out. Just when you think you know how to do something, and you assume your doing it right and whamo...WRONG. When I made the pass thru for the trailing with the dead ignitor, I soldered the wires backwards. Thank God for VOM. Everything is back to normal.
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