Pop & misses- post for a friend

I have a friend who has an '86 ranger with the complete '88 tc set up in it. He has been chasing down a miss on the engine for weeks. I gave him the advice that I got from this website. He has new plugs, new OE wires, cap, rotor and a newer TFI module. The problem was solved for a month and then it came back(even with another set of wires after the first ones). It pops out the tailpipe... so for sure it's a spark issue. Any suggestions for him to look at next? I looked down the FAQ's and some recent posts..... everyone says OE wires.... done already. Thanks.

Check the cam belt for timing and looseness. It may be jumping teeth. The other thing is pull the codes looking for ignition related stuff.

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NATO Member. it's not a vice, it's an obsession
Good judgement comes from bad experience, and a lot of that comes from bad judgment.
88 TC X 2, 86 SVO, mods list at
http://www.turbotbird.com/showroom/pd_88tc.htm

I had a similar problem with my '88 tc, and I tried similar fixes. Turned out the in tank strainer that attaches to the fuel pump had come off the pump and clogged up the screen on the pump intake.