fuel consuption

[spacey64]

i dont kno wut is wrong all of a sudden my cars eats more gas than most V8's:, i kno i drive alot of em. i dont kno my mileage exactly but all i kno is it used to eat about 1/4 of tank to travel 50 miles round trip. or 100 miles cause i make this trip 2-3 times a week and now all of a sudden it ate half tank. im changin spark plugs on saturday so maybe that will improve it. i kno for a fact im getting a spark ping..bad. would that be my problem??? or could it be the injectors, filter, pump, distributer, sparkplug wires, anything im missin? eventually im gonna upgrade the MSD blaster ignition system.
my car also has code 13 on the ecu and i dont kno how to go about fixing it, the only thing i can think of is the a.a.c valve because it says to unplug it when the engine is running rpm should drop and when i did that my rpm did not drop and the connector is bad to it also its all cracked and dry rotted. so would this be part of my problem??? thanx ahead for any help

~mike:

[alllw86]

Code 13....The cylinder head temperture circuit is open or shorted.

Things to check.... Cylinder head temperture sensor harness and connectors......also... the cylinder head temperture sensor

Disconnect the 16-pin connector from the ECU and measure the resistance between terminals 23 & 26 on the harness.

Should be about 2.9k ohms if the head temperture is above 68 degrees F or 2.1k ohms if below 68 degrees F

If you get those readings the ECU maybe bad. If not check the harness to the sensor.

If the E.C.U. is not getting the right temperture readings it sure can and will mess up your gas mileage.

AL