Contour Enthusiasts Group Archives Forums Modifications Zetec Maintenance Acceleration Hesitation

New to CEG - Need Help with Son's contour

My son has been recently having problem with his '95 Contour, 2.0 Zetec, stuttering during acceleration in any gear and revving the engine at idle. It sounds as though the engine is gulping air with no gas to mix with it. Once it overcomes it initial hesitiation (1-2 seconds) it accelerates/revs up fine, although there is a little bit of stuttering when in high gear. Upon initial inspection of this problem I noticed that the timing belt had a fair amount of slack in it and being that the car has 95,000 miles on it, I elected to do some preventative maintenance. The maintenance performed is as follows:

1) Change Timing Belt, main tensioner with spring add-on, 2)water pump, 3)serpentine belt, 4)fuel filter, and 5)routine oil change.

The timing belt slap went away, but the hesitation still remains. Meanwhile, my son informs me he spedometer is no longer working correctly. I proceeded to get the correct speed sensor from my local Ford Store and just recently installed it. The spedometer is now fixd but the hesitation is still there as before, but not quite as bad. I was told by the local Ford shop, that this speed sensor can cause some performance problems as I have indicated, but I was not convinced tht the (2) problems were related. Any thoughts out there? O2 sensor? Throttle position sensor? Anybody else have had this problem?

Thanks for the help!

If that is the only maintenance you have done and it has 95k miles, you have a lot more work to do:: spark plugs, plug wires, pcv valve, clean MAF, clean TB, etc.

Define hesitation. Is it like the engine is stumbling, like you let your foor off the gas pedal a tiny bit and the engine - in any gear - is kinda unwilling to proceed?

Might be 02 sensor, might be TPS, might be dirty MAF... is your kid's CEL on? U might narrow your search down if you could come up with a OBD code.

Hesitation as experienced - Push down on gas pedal to accelerate and engine fails to respond immediately. It will take a second or two for the engine to catch up with the pedal. It acts like a faulty accelerator pump in a carbureted engine, ass uming you are old enough to remember what a carburetor is. (ha, ha)

Any suggestion would be appreciated. The check engine light has not come on as of yet, at least not witnessed by me or by my absent-minded son. If no one has an obvious suggestion, I guess I will have to take it to an experienced Ford diagnostic technician.

Well I already posted my obvious suggestions. Until you do those things, there is really no point in doing more trouble shooting as one of those could fix your problem. Also could be a bad ignition coil. When you change spark plugs make sure to use motorcraft or autolite DOUBLE platinums.

Thanks for the suggestions.

I have pulled the plugs previously and they looked like they are still in good shape, but I will probably change them anyway along with the wires since this is a cheap investment. I don't believe in the double plugs since the spark will only follow the path of least resistance for one of the leads, but it will probably extend the life of the plug as there will be (2) gaps to wear out instead of just one.

sounds to me like it mught be a fuel pump or even a PCV valve. neither is hard to change.

Double platinums are standard on a waste fire ignition system to prevent premature gap wear.

Check your fuel pressure and the operation of the fuel pressure regulator under load.

Check output linearity of the throttle position sensor.

And the usual important stuff:

Clean MAF. Replace plug wires. Replace PCV valve and replace the short rubber hose to it.

Symptoms of an aging fuel pump are increased bucking/hesitation when the fuel tank is below 1/4 level, and power loss at higher rpms (5000 and above).

How many volts do you measure across the battery when the car is running ? Should be above 13.5V. I had similar symptoms when the charging system was going bad and the voltage kept fluctuating, causing ignition and/or fuel supply problems under load.

Tiv