Surging and hesitation, 2005 Ford Freestyle

I have a 2005 Ford Freestyle with 59,xxx miles. My wife and I drive it less than 7,000 miles p/year. About six months ago it began to surge (we had already taken it back to the dealer for some work on a recall related to surges while idling). However, the surge that now occurs is not related to the recall–it can happen anytime, even when on the highway while in cruise control at 70 mph. It makes the driveability of the car questionable. We have had it back to the Ford deal repeatedly, only to be told a number of high dollar things that seem to be based on guesses rather than actual data. No codes have come up with computer diagnostics. We have also taken to independent mechanics, only to be told there is nothing wrong. Only once did a mechanic say that he ‘felt’ the surging when he test drove the vehicle. But even then, the shop said that they would have to do a tune-up (which raised a red flag with me because tune-ups no longer seem to be the proper term to be used with modern engine maintenance). I did a lot of research and as a result I asked a mechanic to test the fuel pump. The result is that the low pressure was 39.5 lbs, and, the high pressure was also 39.5 lbs. They said the fuel pump needs to be replaced ($600). Is it possible that something else is wrong? Such as a relay or other device that regulates power to the pump? Or is it likely that the fuel pump really is the culprit? FYI: All dealer/factory required maintenance for the vehicle has been performed on schedule. Stumped, and, willing to pay for whatever service will correct the problem. Help!

I talk with another ford dealer about this issue.

This sounds like maybe an ongoing problem with the throttle body, which has been known to cause surging on these vehicles. Just because the idle surge was fixed doesn’t mean the throttle body is working correctly now.

Maybe also a faulty throttle position sensor?

Does this have the CVT transmission?

TSB 05-17-5
2005-2006 Five Hundred, Freestyle
2005-2006 Montego
Some 2005-2006 Freestyle, Five Hundred and Montego vehicles built prior to 8/2/2005 and equipped with the continuous variable transaxle (CVI), may exhibit a 50-100 RPM fluctuation. There will be no diagnostic trouble codes (DTCs). The condition will occur at highway speeds, during a steady state cruise or slight tip-in, with transmission fluid temperature below 185°F (85°C).

Reprogram the powertrain control module (PCM) and the transmission control module (TCM) to the latest calibration using WDS release B38.10 and higher or B39.1 and higher. This new calibration is not included in the B39 CD. Calibration files may also be obtained at the website.

WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage

There are tons of complaints to the NTSB on these problems

Yes, this has a CVT, and was purchased in April 2005. Ford has said nothing of the TSB 05-17-5. I will go back to them with a specific request for this. Thanks!

knfenimore, when you write, “Eligible under provisions of New Vehicle Limited Warranty Coverage” are you saying that Ford is saying that it is NOT covered? Obviously, this is a nine year old vehicle.