Throttle Positioning Problems 2003 Lincoln LS 3.9

[Oilslick00]

I have replaced the throttle body, throttle pedal, throttle sensor in my 2003 LS 3.9. Due to engine cutoffs and bucking leaving me stranded several times. It seems to be running well, but using Forescan I get the following,"Code: P0221 - Throttle Position Switch B Circuit Range/Performance". There is some other information such as bent throttle linkage, Mis-adjusted throttle stop.Corrupt RATCH stored in the KAM, SIGRTN open circuit, SIGRTN shorted to VPWR or ground. I could also offer my own colorful language to this perdicament, but I shall stay the straight and narrow course. The throttle body and the throttle were taken from a doner 2004 LS 3.9.. I'm wondering should I reset the PCM, or let it just run and re-learn my driving habits. Enclosed with the truest of Christmas wishes is a graph of the throttle system engine of course running. Any help will be much appreciated. Merry Christmas to all!

 

[joegr]

Most likely, this is caused by RFI from a marginal COP. I recommend replacing all eight COPs with new Motorcraft coils, and replacing all eight spark plugs at the same time. Be sure to verify that the pre-gap'd plugs are correctly gap'd. For every set of eight that I have purchased, at least two or three were set wrong.

 

[Oilslick00]

Most likely, this is caused by RFI from a marginal COP. I recommend replacing all eight COPs with new Motorcraft coils, and replacing all eight spark plugs at the same time. Be sure to verify that the pre-gap'd plugs are correctly gap'd. For every set of eight that I have purchased, at least two or three were set wrong.

Since I've purchased the car, taken a year and a few months to restore it. I didn't think of the plugs, and COPS! Thanks for your answer. For my Christmas present the grandson doesn't know yet but his Christmas present to me will be him replacing them. Thank you and, Merry Christmas!

 

[Oilslick00]

Most likely, this is caused by RFI from a marginal COP. I recommend replacing all eight COPs with new Motorcraft coils, and replacing all eight spark plugs at the same time. Be sure to verify that the pre-gap'd plugs are correctly gap'd. For every set of eight that I have purchased, at least two or three were set wrong.

I would like to ask about the possibility of the VCT sensor being open at idle when they should be closed? I saw a Ford You Tube video about this. Below graph shows mine OPEN the whole time. Any thoughts on this? Thank You

 

[Linc615]

So I had a similar issue I think, if reading your post correctly. It was absolute hell on me figuring it out. And it was somewhat simple. I threw parts at it, nonstop then stopped and read the live data from forscan. So you remember what your absolute throttle position vs obdii throttle position sensor percentage gap is? Have you popped the throttle body apart and checked the gears inside are they intact or chewed up? And the spring have you inspected it? That’s what my problem ended up being.

The threshold for the absolute vs obdii was off by a couple percent if that causing failsafe mode the second after cranking. It was the spring and a minor adjustment was needed to tune it back where it was happy. I forget how much the spring likes to be wound up. I (think) it was only one wind and it was happy. The thing that is mounted on the soring with the little holes where it locked into was worn causing it to slip out I think. But a new one corrected it. Before fixing tho the stepper motor inside the TB went haywire and shredded the teeth off the gear I guess bc it lost tension I’m not sure. Hope this helps

 

[Oilslick00]

So I had a similar issue I think, if reading your post correctly. It was absolute hell on me figuring it out. And it was somewhat simple. I threw parts at it, nonstop then stopped and read the live data from forscan. So you remember what your absolute throttle position vs obdii throttle position sensor percentage gap is? Have you popped the throttle body apart and checked the gears inside are they intact or chewed up? And the spring have you inspected it? That’s what my problem ended up being.

The threshold for the absolute vs obdii was off by a couple percent if that causing failsafe mode the second after cranking. It was the spring and a minor adjustment was needed to tune it back where it was happy. I forget how much the spring likes to be wound up. I (think) it was only one wind and it was happy. The thing that is mounted on the soring with the little holes where it locked into was worn causing it to slip out I think. But a new one corrected it. Before fixing tho the stepper motor inside the TB went haywire and shredded the teeth off the gear I guess bc it lost tension I’m not sure. Hope this helps

I haven't popped the throttle body apart yet. I did get a used one from an 04 LS. I had a code p0223 a confirmed TPS. So I replaced the TPS with a brand new one and no engine light nor codes have been reported. However, I am thinking of taking the throttle body apart to check if anything is wrong with it just to make sure. It quit running on me yesterday in charlotte NC and lucky for me I ran into a guy from Oreilly's and got a new TPS. Just curious, when taking the throttle body apart does the spring pop out all of a sudden or can you take it apart examine it and fix if possible. A new TB is around $500 to $600. Springs are cheaper for sure. I very much appreciate your answer on this. I'm going to also take a look at my logs to make sure I understand what had been going on in the TB.