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rebel_cowboy
Jul 29, 2008, 02:54 PM
I have a 99 ford escort zx2 that feels like it is not getting its fuel when you press the gas pedal. It will (hunch) when you press the gas to hard when pulling out or shifting gears. New fuel filter, plugs, plug wires, and new coil. The air sensor has also been replaced. p.s. it only does it when you get the car to about 3000 RPM's. What is the problem?? Please help!!

TxGreaseMonkey
Jul 29, 2008, 05:23 PM
I like all of what you've done. Did you install the same Motorcraft spark plugs, properly gapped (.054 in.), that originally came in the car? Many aftermarket plugs perform worse, are gapped differently, and cost more than OEM.

Try disconnecting the negative battery cable and resetting the PCM. Record any radio codes first.

rebel_cowboy
Jul 29, 2008, 05:49 PM
All this has been done. And yes they where replace with motorcraft no codes are showing and already have reset it by removing the terminal

TxGreaseMonkey
Jul 29, 2008, 05:52 PM
I know you don't have an Ignition Control Module on your car. If you did, I'd say replace it. If nothing else jumps out at you, check the Crankshaft Position Sensor and engine compression.

rebel_cowboy
Jul 29, 2008, 06:08 PM
Cps has done been replaced. To tell you the truth it acts like you are patting the throttle when it does it see I bought the car from my cousin and he had already replaced some of the stuff for me. Was thinking about replacing the screens on the fuel pump and having the preasure checked on it! When you are driving it feels like it is some where in the fuel! But you know some have sensors that will cause them to do it and some time the computer will too!

TxGreaseMonkey
Jul 29, 2008, 06:14 PM
. Check fuel pressure.

. Check fuel pressure regulator.

TxGreaseMonkey
Jul 29, 2008, 06:26 PM
Fuel injector duration is controlled by the oxygen sensor. Has the oxygen sensor ever been replaced?

CaptainRich
Jul 29, 2008, 07:19 PM
Fuel metering is critical. Besides all that has been done so far, has fuel volume been tested?
Pressure can be one thing, but you also need volume.
Don't over look the Mass Air Flow (MAF) sensor as a possible culprit. Without the proper input from the MAF, the Engine Control Module (ECM) can't completely control fuel trim like is should.
Does the problem occur more when the engine and exhaust have gotten to operating temperature? You may be having catalytic converter problems.
Let us know.

TxGreaseMonkey
Jul 29, 2008, 08:05 PM
CaptainRich makes a good point. MAF Sensors are expensive. You might want to buy a can of CRC MAF Sensor Cleaner and see if that solves the problem.