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Discussion Starter · #1 ·
Hey guys, just joined the forums and I'm hoping someone can help me fix my problem. Ill start with the previous week before this started. Finally had my car running great after I did the head gaskets. I was driving along and the roads were pretty bad and I went through a big puddle. A few seconds later my car started shaking and the tach started flipping out. I broke down on the side of the road and had no spark from my coil or to my plugs. I figure it was just the tfi, so I leave my car in a parking lot and come back later, swap out the tfi and it fires right up. From that point on my lacks power through most of the rpm range. At about 4 thousand rpms at WOT or even half throttle, the car starts to misfire like crazy, loses all power, tach flips out going back and forth. What I have done so far is replaced my plugs with autolite coppers gapped at .45. New spark plug wires, new coil, an msd ignition box, cap and rotor, and remanufactured distributor from autozone. I checked my tps voltage checks out good along with a nice clean voltage sweep, checked and cleaned all grounds, 2 new o2 sensors, cleaned MAF, and cleaned and checked all grounds. My fuel pump and filter were replaced about a year ago. I'm pretty certain the miss is ignition related because of the tachometer behavior. I checked under my hood in the dark and saw no arching. I tried 2 different ignition modules from autozone, seems kind of strange that it ran fine until it broke down then ran like crap after changing the broken tfi. Messing with my timing doesn't help. I have run out of ideas. I'm leaning towards bad remanufactured distributor and or bad quality tfi. I also replaced my ecu. Any advice on where to go from here is appreciated, and sorry for the long ass paragraph.
 

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Discussion Starter · #4 ·
Thanks for the reply, I have replaced it because it came with the reman distributor. The symptoms still point towards it though, I might try another new distributor
 

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Aftermarket TFIs are garbage. I'd replace it with a Ford TFI first before you try anything else. BTW, I personally wouldn't trust that MSD box, even if it's brand new.
 

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Yeah, I'd put everything back to original, especially the TFI and MSD box. It sounds like you got something wet and it just needed to dry.

I freekin hate problems like yours!

Let us know what you find.
 

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Twice, with two seaparet vehicles, i have seen a higher rpm problems, in which we troubleshot all manner of possibilities. After making numerous changes on the drag car, we watched the voltages and noticed that it was going whacky right at the troublesome rpm. So, we disconnected the drive belt and reved the motor. It zinged to no end. We swapped the alternator and regulator and it fixed it.

The second time, a whole different car (typical fox body with sbf)i relayed the same info to the owner, who immediately scoffed and went on about his merry troubleshooting way. Guess what? His problem was charging issue too.

I am not saying your problem is a charging issue, but at least narrow it down that it isnt a voltage/charging problem.
 

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bypass msd.

check all grounds. <--- good chance thats where you problem lies. but Ive seen msd boxes crap out and do the same thing

get the schematic and trace the supply ground for the pip. check anywhere there is a terminal connection
 

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Twice, with two seaparet vehicles, i have seen a higher rpm problems, in which we troubleshot all manner of possibilities. After making numerous changes on the drag car, we watched the voltages and noticed that it was going whacky right at the troublesome rpm. So, we disconnected the drive belt and reved the motor. It zinged to no end. We swapped the alternator and regulator and it fixed it.

The second time, a whole different car (typical fox body with sbf)i relayed the same info to the owner, who immediately scoffed and went on about his merry troubleshooting way. Guess what? His problem was charging issue too.

I am not saying your problem is a charging issue, but at least narrow it down that it isnt a voltage/charging problem.
I have not run across this problem yet, but a buddy of mine says he has found it many times, mainly with Chrysler crap. But he has also run into it with imports and GM vehicles also. The problem turns out to be one or more diodes in the alternator have gone bad, so the alternator produces AC voltage, instead of DC voltage.
 

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I always poke fun of MSD because it stands for My Spark Disappeared, but I have to say, I chased a high-rpm/high-load misfire for an embarassingly long time, swapped out parts-store coils a few times, and it wasn't until I installed an MSD 5527 Street Fire coil that the problem was totally cured. I picked it over the 8227 because it claims a higher turns ratio, higher max voltage output, and higher peak current than the 8227.
 

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I chased symptoms like this for a year. Replaced EVERY ignition component there was, except ONE thing.... The distributor itself.... Replaced everything inside, TFI, you name it....

Dropped in a new dizzy, and bingo.... 6200rpm shifts for the next 2 years and never skipped a beat.
 
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