Misfire under boost

[Choochoochoo]

I get a misfire under anything more than say 7-9 psi, I know it could probably use a tune up so I was going to start with plugs and wires, any suggestions for plugs? As far as I can tell, it will reach about 18psi max, but to my knowledge it's mostly stock.. The guy I bought it from said it has the e6 manifold, the borla exhaust, and possibly a 3" down pipe, but that's it. Any help is appreciated! Thanks guys!

[John Brennan]

Most of us swear by Autolite 764's. Stay away from anything Platinum or multi-electrode-- not needed and confuses the engine management. Motorcraft OEM are good, too, and some like NGK's. For wires, Motorcraft are good; I have gotten the best results from Magnecors-- the only wire that holds up long-term, in my experience. Don't use cheapo wires, they won't hold up. Check timing, TPS, idle, run codes.

[Choochoochoo]

What is the timing supposed to be at? I did notice this morning my idle is hovering at 1000 which, unless I'm wrong, is a little high... I also just noticed that at half throttle I don't notice the misfire until close to redline..... I'm just guessing here, but it seems as though my timing is off. The previous owner mentioned something about having an intercooler on it at one point in time, could it be possible that timing was changed a bit to account for the intercooler and possibly more boost?

[John Brennan]

All TurboFord EECIV's are set to a static 10* BTDC, with SPOUT disconnected, EXCEPT for the PF-Series, which are set to 13* BTDC, and are exclusive to 5-speed XR4Ti's.

[Choochoochoo]

So plugs did the trick! Now my new problem. It pulls hard all the way through first, but second goes hard till around 4000 or so and then feels like it just kinda falls off. Almost like a soft touch rev limiter. What gives?

[Mike McCreight]

How accurate is the tach?
What did you gap the plugs at?

[Choochoochoo]

As accurate as a stock tach can be, gapped at .30.... Not enough gap? Too much?

[Choochoochoo]

So, I pulled the plugs, re gaped to .032, and as I was getting everything going for a timing check I noticed that my #1 injector was making a mess of things.. Fuel everywhere.. So I think I may have finally found my problem. Hopefully it's just o rings, as that's an easy and cheap fix. Here's to hoping I cure the ailment my cars been having! Thanks for everyone's help!

[sabre]

If you have the original factory brown-top injectors, then don't be surprised if it is the injector itself.

[Choochoochoo]

Yeah.... The whole tip was broken.... And all the parts stores are closed... Bummer.... Hopefully there's an injector at one of these stores tomorrow......