I apologize if this issue has been addressed before, I could not quite find what I was looking for in previous threads. I'm starting to be at my wits end trying to sort this out. Any help that can be offered is very much appreciated.

A little backstory, I was in a bad accident in my '09 ranger back on September 13th. I Watched it catch on fire after the crash and I had to put my dog down after he broke his back riding shotgun with me when we went off the I95. Unfortunately my toolbox with all my tools was also burned to a twisted hulk of steel in the fire, and I don't have the tools to repair a lot at the moment.

I decided to purchase another ranger, a 2006 2.3L 4-cyl, essentially the same truck I had, just an older model. After addressing some issues she had when I first bought her, including a blown head gasket from the last shop not machining the parts properly, I took her for a nice long test drive to Nashville and back.

Approximately 100,000 miles
No Engine Codes
The engine sounds and feels to be running well, one shop did say they were reading misfires when the rpms reach a certain point.

I noticed that on hard acceleration and on long uphill slogs she loses power at around 3000rpm, sometimes less on the long climbs. I can coax her up to a decent speed and maintain around 2,500rpm-2,750rpm, but she will drop anywhere between 500rpm and 1,500rpm, if I feather the gas a bit she will resume running but the issue will return.

I have changed a lot of parts on the truck already, and I took her into a shop to let them look at it rather than trying to chase my own tail for days. I am supposed to move out of my place and down to Florida on the 15th of November, and this is causing a lot of headaches for me and delaying a lot of plans.

One shop thought it was the torque converter. This didn't seem right to me, but I took it into a transmission shop and they said the transmission is fine. I took it into another shop and after they test drove it they wanted almost $1000 to put in new plugs, wires, possibly an ignition coil, and do some sort of air system clean out. I informed them that myself and the other shop already changed the plugs and wires twice, and I had put in a new air filter. When I told them the other shop had also adjusted the timing, advanced it I believe, they wanted to take another look at how she was acting and more tests to run. The other shop advanced the timing without prompting when they had the valve covers off to do the head gasket. The owner had said that he had noticed the truck idling low and almost wanting to stall when it was sitting in idle. I don't recall this from when I drove her, but I wasn't in a position to argue when I picked up my truck the other week. That being said, I did not notice this issue when I drove the truck back an hour and a half from that shop home the other day, this issue didn't appear until I was going up the long mountain grades on the way to Nashville.

I have a background in maintenance work and electrical work. I am not completely lost in the sauce when it comes to troubleshooting and fixing things, but I am not an automotive technician. If anyone has some ideas I could point the shop that has it now to that would be helpful.

As of right now my best ideas are the CAT starting to go, I had two of them go out in my old ranger and never throw a code, and backpressure at higher RPMs causing misfires or loss of power, or the timing adjustment causing the ECU to be too far out of its programming and misfiring. I did have to disconnect the battery when I had my hands inside of the dash repairing the shift indicator, maybe it reset it to factory condition, and it is too far of an adjustment for it to just "relearn" during driving.

My sincere thanks to anyone who reads this and can provide some answers. I don't know y'all from Adam, but if you can help, you will be helping out a man in a tough spot.

 

Just as an update. Decided to coast easy down to Florida where I have space and tools to work, and friends with experience.

I did rule out the CAT. Still no codes. Upon further driving I think the issue is either related to the timing, or just bad luck to have something else go out on it. I actually have a hard time thinking it's the timing, as on my 70 miles long drive back from the shop that adjusted it I never experience anything like the bucking or rpm drops I am now. She drive fine.

I'm going to replace the throttle body, and the throttle position sensor, and see if that helps. Afterwards of it is still acting up I'll go in and reset the timing to the factory preset and change the fuel injectors while I have the engine partially disassembled.

 

Why not check fuel pressure and flow volume? Lack of either or both would cause the engine to lose power at rpm, and work better if you feather the
gas pedal. Volume check by catching the fuel in a container for a measured time, do the math, and get flow in GPM - gallons per minute. I think
the flow should be near 6gpm, but there is likely a spec published by FoMoCo.
Climbing a hill(try to find on in FL ha!!) is a good way to check for fuel flow problems. The demand is likely at its highest when climbing, and is of
duration so you won't be fooled by 'enough' to go for a short while, but failing after a good long climb.
Anyway, my first thought is fuel problems.
tom

 

I did check the fuel pressure, but I didn't check the flow rate. It was starting to suffer the same issues and misfiring on the I95 heading into Savannah. Rather flat ground, but it doesn't hurt to check.

 

Have you ever had a gauge on a pressurized system, showing high pressure, and bleed off a teaspoon of fuel? The
pressure will drop to close to zero right away. Pressure is 'easy', it is volume that is needed to climb a hill or have
good acceleration.
Attach a pressure gauge, power up, read the gauge, and then push the 'relief' button. The pressure will drop
like a rock.
FWIW.
tom