[7up]

I have a ford taurus 2005 with transmission trouble.when the car is cold the trans shifts normal,but after a while of driving and every time I come to a stop and then start driving the trans has a very hard shift into second gear.I've change the filter has plenty of fluid so what would cause it to hard shift also at a stop in gear the idle speed drops as if it wants to die.also there are codes p0171,p0174,p0300,p0316 PLEASE HELP

[TxGreaseMonkey]

Go over the ignition system thoroughly--you are experiencing serious misfires. Replace the spark plugs (Motorcraft only), if they have not been changed in 3 years or 50,000 miles. Coat the porcelain portion of the plugs with dielectric grease and check the gap. If you have the Vulcan engine, you may need to replace the coil and spark plug wires. Part of the problem may be vacuum leaks;e.g., upper intake manifold, PCV elbo hose, and valve cover hoses (front and rear banks). Tauruses are very sensitive to air leaks. I would also replace the IAC Valve (Motorcraft only) and gasket, which may be affecting the idle speed.

Full synthetic ATF has dramatically improved the quality of upshifts and downshifts on Tauruses I've worked on.

[TxGreaseMonkey]

FYI regarding your transmission:

This year transmission (2003 Taurus and newer) had an issue with the pump shaft splines stripping out in the torque converter. When the splines strip out, the pump no longer turns and the car will not move. If the fluid is suddenly overfull on the dipstick with the engine running, this is most likely the case. To verify the issue, a pressure test should be performed. If there is no pressure, the splines are likely stripped. The converter must be replaced, but it usually does not damage the shaft. Dacco's replacement torque converter, available through AutoZone, eliminates the problem by increasing the thickness of the female spline "washer" from .160" to .230".

[7up]

Go over the ignition system thoroughly--you are experiencing serious misfires. Replace the spark plugs (Motorcraft only), if they have not been changed in 3 years or 50,000 miles. Coat the porcelain portion of the plugs with dielectric grease and check the gap. If you have the Vulcan engine, you may need to replace the coil and spark plug wires. Part of the problem may be vacuum leaks;e.g., upper intake manifold, PCV elbo hose, and valve cover hoses (front and rear banks). Tauruses are very sensitive to air leaks. I would also replace the IAC Valve (Motorcraft only) and gasket, which may be affecting the idle speed.

Full synthetic ATF has dramatically improved the quality of upshifts and downshifts on Tauruses I've worked on.

I think I've found the problem,I measured the primary ign plug on the coil pack and it was 08.6 ohms on all of them,then I measured the six plug towers on the coil pack it was 11.5 kilohms. These radings are not even close to the specs.so I'll replace that see what happens