So, the sensor went out on my fuel pedal assy and it was giving me grief. No response when I hit the pedal, no power, no turbo....
The new pedal has breathed life into my 7.3 (I just bought it from my dad and was disgusted at the performance, it's way WAY better).

Here's the problem. $695 later the new pedal works great, AFTER it doesn't work at all. I start the truck and it does not respond for 1-60 seconds. Then it works great. Doesn't matter if the truck is hot or cold.

Shop says they think it's "normal."

It's not normal.

Anyone else have this issue?

Thanks -

AKFUZZYDICE

 

Did you buy a whole new assembly with both the Throttle Position Sensor (TPS), and the Idle Validation Switch (IVS) ?

 

I happen to have this issue. A new IVS did not fix mine. VERY long story, I let mine idle while it warms up. The pedal never works until it idles for 1 minute. It's been that way for two years now and I have just learned to deal with it and don't even think about it anymore. I have hated the TPS setup in these trucks from day one, but prolly because mine has given me fits more than most here. I would say just roll with it as long it drives reliably. It's good to let the engines idle for 5 minutes anyway so they warm up a little. That's been my routine for 2.5 years now. No issues.

 

It would be interesting to get this truck on a device that reads real-time data, and read TPS position and IVS state as seen by the PCM while this is happening. It would also be interesting to see if the time-out corresponds with the GP run time. Just spitballin' here, but I can't help but wonder if, while the GPs are running, system voltage is so low that IVS state is not being properly read by the PCM.

Quick dumb-guy test of the theory - turn the key to RUN for 10-20 seconds, then DISCONNECT one of the small terminals (the one that's NOT red/green would be the best choice) from the GP relay. THEN start the truck, and see if the go-pedal responds immediately.

 

I would be really curious to see this as well. This issue has boggled my mind for years and I would like to see it resolved. Again I deal with it and it doesn't really bother me, but it would be nice to know what the issue is because I tried everything that I know of.

 

Do you have AE or anything that can read live data? Maybe you could try the test I suggested, disconnecting the GP relay.

Does the delay seem longer when the engine is cold, and shorter when it's hot?

 

I don't have AE, but might invest after the first of the year. I run an Edge CTS Insight for monitoring. It does read codes and such, but no real live data that I know of and I played with it quite a bit.

Come to think of it though, it does seem to need more time in the morning than during the day to go through the procedure I put it through. You might be on to something. On occasion, it will even work right when I start it up, but I hadn't felt like there was a correlation other than a fluke. I'll try this test in the next day or two when I get a minute to breathe and see what I come up with. I'll report back. If it does happen to be the issue, I wonder what the fix might be. I have replaced the TPS twice and the IVS once. I have spares of both. I'll let you know what I find. Thanks for the mental kick in the pants!

 

Another thing to look for - when the GPs cycle off, the voltmeter swings from left-of-center to right-of-center. See if that moment corresponds with when the go-pedal becomes active.

 

I'll do that this morning when I warm it up before work.

 

Did you guys adjust the tab on the peddle that actuates the IVS? It sounds like it is adjusted a bit sensitive, called the "IVS MOD". When starting the truck if the PCM does not see the IVS at idle position it will ignore the TPS.

In a quiet location with keys in your pocket press the peddle by hand slightly then slowly release the peddle and you should hear a click, the IVS switch activating. If not then you have found the problem.

The only way to adjust it is to bend the tab slightly. See link below, post #8.

https://www.ford-trucks.com/forums/7...mod-today.html

 

Ok, so a little update. First, Jim, my tab has been adjusted numerous times along with me removing the IVS from the pedal altogether for better driveability. It does not seem to be the issue.

MP, I disconnected the GPR and no change as well as waiting for the GPR to go off when I warm the truck up and still no change. I definitely think it has something to do with engine temp. The reason I think this is because the "Warm up" time waiting for the TPS to function is less when the truck has been driven. I timed these events. In the morning upon cold start-up, it takes 2:30 before it becomes operational. If I do a warm start-up, it takes 30-35 seconds every time. What has been explained to me by a 6.0 guy is that he thinks it is the time it takes for the PCM to "close loops" while warming up. Once it gets to the TPS and sees the temp, it "checks it off" so to speak. (I know...6.0 guy with 7.3 knowledge so take it for what it's worth). I have been at a loss for an explanation to this problem for over 2 years now and have tried everything I know short of replacing the harness. For a time, I was really under the impression that the wiring between the IVS and the PCM had gone bad or brittle, but I exposed the wiring when I first started having this issue and found it to be pliable and in good shape. The reason I have learned to live with this issue is because I have run out of ideas and anyone I have asked about it (JW, Travis, Bill, etc) seem to be at a loss as much as me. They have never seen this before. In fact, no one has! The truck did not do this when I first bought it. It only started doing this after I got a CEL and a dead pedal a few months after purchase and had to replace the TPS. The problem started immediately after. I have been through 3 TPS sensors and finally have a good one that seems to work well and not have erratic voltage output. I have two good IVS sensors as well. I have also watched the voltage output like a hawk on my Edge and there is no correlation. It puts out 100% every time and climbs steadily as the throttle is applied like it is supposed to.

So, all of that being said, suggestions are more than welcome. I could start from ground zero and go through it all again, but I have been through this thing so many times that I'd need a decent probability that the issues can be resolved before I'd tackle it again. To recap, good known TPS with two spares, two IVS switches that both function, seemingly good wiring short of a new harness, good GPR, new GPs, and that is about all I can think of. Hope this sheds some light on what might be happening. Thanks for listening.

 

Sorry for the VERY late response. I bought the entire assembly. EXPENSIVE OEM parts. The part was bad. My mechanic pulled it off, put a multi-meter on the switches, and it wasn't switching 1/0 until they tapped on it with their finger. Dropped in yet another new part and it worked just fine. Seems to run/drive better, I think the turbo is working again as well.

 

Yep. I bought the enter assembly, Ford parts.
Part was bad.