My Ranger might be dying but I want to save it! It's a '93 4x4 Supercab with the 4.0L and only has 140k miles.

The main symptom I'm experiencing is intermittent power loss. This became most apparent when I was recently driving across the country towing a small U-hual trailer while a 500 lb motorcycle was in the bed. The truck would drive normally for most of the time and then several times an hour a very noticeable loss in power would temporarily occur for a few minutes. I could easily cruise at 60mph but during the power loss the truck would slow down to only 35mph. During the power loss the throttle felt useless. The power would then unexpectedly kick back in and I could drive normally until the next occurrence.

I read out the codes from the check engine light and here they are. They were cleared recently and these are the latest codes.

172 System indicates lean bank #1
173 System indicates rich bank #1
176 System indicates lean bank #2
177 System indicates rich bank #2
181 Adaptive fuel rich limit reached at part throttle, bank #1
211 Profile ignition pick-up circuit failure
332 Insufficient EGR flow detected
336 EGR circuit higher than expected
337 EGR valve pressure transducer / position sensor circuit above maximum voltage

Just from the feel of how it drives during the power loss, I suspect that the fuel mixture is going wrong. The codes seem to support this.

Fuel pressure checked out good. Spark plugs, wires and coil pack are good.

My best guess is that the 02 sensors are bad. Any thoughts or help?

Thanks!

Vacuum leak at the intake manifold.

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1999 Ranger 4.0 and extreme Snap-on tool fetish

Remove EGR and test for function with vacuum. Also check the passages for carbon build up. IF you have O/D, dont use it while hauling and towing. Check for vacuum leaks on the lines and intake gasket. Replacing O2 sensors may not be bad idea if they are originals with that mileage. A tune up is in order if it hasn't been done either. Filters, plugs, wires etc...

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1995 Ranger XLT 3.0L OBDII
Trans: A4LD (E) 2WD
Rear: 7.5 / 3.45 NL LHD
Tires:GY P235 75/R15 (orig 225 70/R14)
Long Bed, 20 Gal Tank
Up to 229,900 miles

I agree with Grumpa

Keep it simple check the basics, first remove the fuel filter drain it then try and blow though it. if you get a lot of resistance or back pressure replace it.

I suggest checking the fuel filter because even with good fuel pressure you may not have good enough volume

and defiantly check for hard brittle cracked or otherwise damaged vacuum lines.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears