2000 ford taurus FFV bucking/surging no cel

[Jamesr1981]

2000 ford taurus 3.0L FFV 12 valve vulcan 108,000 miles

Hello, I am lost for ideas I have installed new plugs, wires, iac, dpfe, dpfe pressure sensor, egr valve , tps sensor and coil pack. On cold mornings after the car sat all night it starts up but the rpms stay around 1200 rpm it feels the engine is shaking. also a noticble miss is heard in the exhaust. after a few minutes this goes away. and the car then seems to buck under load Ie going up hill or going past half pedal. otherwise it drives fine. I have taken a look at the live timing info with my odb2 can scanner and have gotten this while holding the idle at 1,500 steady.

Bank 1 Sensor 1 02'S output .285V
Bank 1 Sensor 1 Stft 4.6%
Bank 1 Sensor 2 02'S output .825V
Bank 1 Sensor 2 Stft 99%
Bank 2 Sensor 1 02'S output .120V
Bank 2 Sensor 1 Stft 5.4%
Bank 2 Sensor 2 02'S output .090V
Bank 2 Sensor 2 Stft 99%

Stft bank 1 4.6%
Ltft bank 1 -5.4%
Stft bank 2 .07%
Ltft bank 2 -6.2%

Maf Rate 1.1 lb/min

Moniterd fuel pressure in 10 second increments Psig
39.1
40.4
38.6
39.5
39.1
39.1
38.6
39.5
40.8

Im thinking I need a new fuel pressure regulator but the 99% readings dont look normal and have no clue as to what they mean. Thanks in advance for your input.

[behlinla]

The 99% fuel trim values are null, so don't worry about them. Your scan tool should just ignore them rather than reporting them. Your fuel trim values show the engine is running slightly rich, but really not enough to be overly concerned. The rest of the data looks okay.

What you need to do next is to actually check for spark. Sometimes you get bad replacement parts, and I think you might have an ignition issue. Perform the test in the video and make sure the spark jumps a good inch or so.

How to perform a cylinder drop test - YouTube

How to perform a cylinder drop test - YouTube

[downhill]

Clean the MAF and do new air filter. Check vacuum hoses. Usually affects the idle. Is the PCV in good order??

[Jamesr1981]

Drop test completed all cylinders had at least a 1 inch spark. I have a new vaccum line assembly and there apeears to be no vacum leaks. I am gonna try changing the plugs and wires today again the ones in are 2 yrs old. wich i thought was fairly new.

[davepett]

My 03 Vulcan did this when the CPS went, it would buck when RPMs went above 3000 (OD off going up a hill). No CELL.

[Jamesr1981]

New wires in and the problem is still there. I will try to get video of a cold start tomorow morning. I seen in a youtube video a guy with a simaler problem had a bad fuel pressure regulator. but at a cost of 172.99 I dont wanna change is based solely on a video. Davepett when your cps went was it the entire assembly or just the top ?

[sheila]

Cmp= camshaft position sensor. Ckp= crankshaft position sensor. Cps= nothing, lol.

[downhill]

Did you clean the MAF and new air filter yet?? Give air to make things not buck, cheap try!!

[Jamesr1981]

I am gonna try this tomorrow.

[WJC]

You've confirmed your fuel pressure is good, and I think the 2000 is returnless anyway (no regulator). I think...

With a high end scan tool you can watch active misfires (Ford calls it misfire %) even if they don't set a misfire code. You may not be able to do that with your scan tool.

Those flex fuel modules have been known to go bad, too causing incorrect fuel trims. I have no idea how to test them , though...