92 ranger xlt v6 4.0 transmission replaced, fuel injectors replaced, heads new, engine replaced 500 miles on engine. Had multiple mechanics look at it but they can't figure it out. Truck wont go faster than 20mph Any ideas?
Either you have a blocked exhaust like a bad converter, a muffler clogged from a broken up converter, or you have a bad ignition module or fuel pressure problem. First try replacing the fuel filter to see if it is clogged. Check to see if the fuel pressure is at 40 psi. If this is okay, then see if the exhaust is blocked. If you would like another opinion on the car, a certified pro from YourMechanic can inspect the acceleration issue and let you know what should be done.