1993 Ranger 2.3 4 cylinder 8 plugs. Used to get 27 miles to the gallon and except for really steep grades do 75 no problem. Now it better be down hill and milage has dropped to 20. Good mechanic trying to find problem, running tests, not c converter, not fuel pump or filter, not injectors, one odd thing, the abs light comes on not long after you start it up. But what does that have to do with acceleration, nothing in manuals on that, brakes are fine. Egr valve is fine. nothing showing up in any testing, so far. Anyone got any insite on this? Since no one has died in it haunting can’t be the problem.
So now we have had everything tested out twice and still no solution. Could the speed sensor in the braking system affect gas mileage and power?
Pre mechanics instruction, drove in 5th as fast as it would go, 60 tops. MPG 17. Then drove same route as fast as it would go without going over 60 to protect engine, in 4th and got 21 MPG. Does this tell us anything? I hope it tells the mechanic something. I think the ABB speed sensor and the Vehicle Speed Sensor are not sending the proper signal to the Little box on the firewall that I can’t remember the name of that sends signals for fuel and such to other parts of the engine and electrical system. Any ideas?
New plugs and wires would be a good start if they haven’t been done in a while. Outside of that, I do have a shot in the dark for you to consider. You might try changing or at least checking the timing belt. I had a customer once who had a Mustang with the same engine as your truck towed into the shop with a broken timing belt. All I did to that car was replace the timing belt to get it running again, but the guy called a few days later to report that he had better performance and fuel economy than he had had in years with that car. I have no real idea why, but perhaps something was wrong with his timing belt or valve timing that installing a new belt cured. It’s worth a shot, and your truck is probably due or overdue anyway.
It has new plugs and wires and mechanic has even checked to make sure they are right. Timing belt was changed on time per maintanence schedule. But at your suggestion we had the mechanic look at it and it is fine. Valve timing has been checked, in fact all test run have come out very near to what you would expect if it was brand new. Some tests the mechanic has even run twice , changing testers, just to see if that might be it. So now they are running some test they did before,only with the exhaust off at the manifold, looking again for clogged exhaust, that is what it acts like. Anymore ideas?