97lariat-SA

Hey, guys. I'm new here, and could use a little help. Just picked up a 97 5.4 Lariat 4X4. The truck is fine except for a skipping issue. When I first bought it, I took it to my mechanic and he did a full tune up. Plugs, coil packs, PCV valve. The works. It was fine for about a week or so. Then, it started cutting back in the upper gears, especially OD. The truck jerks and rattles, cuts back, and lopes out of the tail pipes, almost like it's misfiring. But when you hit the throttle and it downshifts, it evens out like there's no issue. I'm stuck on this one. Any help would be appreciated.

hamiltonjayson

Are you getting a check engine light? I had the same issue and it was a bad coil pack.

hamiltonjayson

Also check to make sure the injector plugs are on good. Sometimes the clips that lock them on get old and break.

97lariat-SA

That's the weird thing. There's no engine light or codes thrown. There maybe an engine light on and my bulb is burnt out.

hamiltonjayson

If you don't have a code reader to check, you can always go to auto zone or somewhere like that & they will hook it up for free. But the check engine light should light up when the key is initially turned on as a check of the gauges.

97lariat-SA

I've got a Superchips handheld tuner I used on my old Mustang. It reads DTC'S. And when I plugged it in to my OBD-II port, nothing popped up. I'll take it to Auto zone and have them hook it up though, just as a 2nd opinion. Thanks for the help.

FordTruckMotorsport

EGR valve ?