‘94 Sputtering over 3000rpm

[94wkndwarrior]

So I just bought me a 1994 Ford Ranger. It’s a 4.0L 5spd with a 4” BDS kit and James Duff long arms on 33” Buckshots. Nice rig with super clean interior. After completing the paperwork, I hop in and take off home. Driving through the neighborhood at speeds under 50mph, it’s strong, the clutch pulls hard and no CEL. Then I jump on the freeway and in 4th gear at speeds over 3000rpm, it begins to sputter and lose power. I put it in 5th and gain speed up to 65mph, and then it begins to hesitate/sputter again at 3000rpm. This time it throws a CEL. I haven’t ran a diag on the CEL, but want to see if anyone else has experienced this? Previous owner claims new fuel pump, fuel filter, plugs and wires. I have researched the heck out of this and I am thinking it’s something with the rev limiter or clutch assembly...
Thoughts anyone?

 

[superunknown98]

Does it happen more when you have engine load? like going up a hill? You can try to clean your MAF sensor with special spray. You can spray it into the intake tube near the MAF or you can take the MAF off the intake tube.

 

[94wkndwarrior]

Thanks for the reply!
Previous owner claims to have cleaned the MAF. My intention is to inspect the MAF. So far I have been too busy to dig into it.
I first noticed the hesitation when I got onto the highway. I took it into high RPM’s in 3rd getting onto highway from what I remember. It wasn’t until 4th that I felt it sputter/hesitate at around 3000rpm. Then again in 5th. Maybe I just didn’t notice it in 3rd. But I haven’t driven it since.

 

[sd359]

Does it have motorcraft o2 sensors. I had 2.9 that would not run correctly on Bosch. As long as I was accelerating or decelerating it was fine but at 55mph or steady speed it would miss and black smoke would pour out the pipes. After many days of chasing problems, I contacted our Ford dealer and spoke with a tech and he told me that Rangers for some reason did not like Bosch o2 sensors. I have a bosch in mine now and no problems but you never know Fords can be picky some times.

 

[Broosedamoose]

My truck was doing the exact same thing for a couple weeks before it blew a head gasket!

 

[Ramcharger90]

Maybe clogged cats. I did a motor job where the cats were that clogged it blew the head gaskets. We didn't realize it until the new motor was in and it hesitated really bad at about 2500 rpm.

My truck was doing the exact same thing for a couple weeks before it blew a head gasket!

 

[94wkndwarrior]

I will double check who the mfg is on the O2 sensors. But it is not smoking at all. Just hesitating. I also need to check the cats on it. Never considered that as a possible reason.
I will post the solution once I get it figured out. Thanks for all the feedback.