Typical TPS readings?
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Typical TPS readings?
I just got an Equus 3130 code reader to troubleshoot some driveability problems with my '99 V10. I suspected a bad coolant temp sensor, and it's reading confirmed that... and when I looked under the hood, it turns out the sensor is not even installed, it's hooked to the harness and zip-tied to the harness, not in the head! Gonna fix that right away, but some of the other readings on the device seem questionable as well.
The %TPS at idle is reading around 19%, which seems a little high to me. Also the calculated load seems high, it's around 30% at idle, and just light low speed cruising can be around 40-50%. If the TPS was reading high, I'm thinking it would cause it to calculate higher %load, correct? So I guess what I'd like to know is, are these readings typical, or high? At full throttle the %TPS reads around 95%, not 100% but I'm assuming that's close enough. Any thoughts?
The %TPS at idle is reading around 19%, which seems a little high to me. Also the calculated load seems high, it's around 30% at idle, and just light low speed cruising can be around 40-50%. If the TPS was reading high, I'm thinking it would cause it to calculate higher %load, correct? So I guess what I'd like to know is, are these readings typical, or high? At full throttle the %TPS reads around 95%, not 100% but I'm assuming that's close enough. Any thoughts?
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I think your TPS and load readings are normal. I installed a Scan Gauge last spring and the TPS ranges from 14-16% at idle to 76 at full throttle. I asked the guys at Scan Gauge about this and they said that is the way that the voltages that Ford uses reads out. The difference between the full throttle readings may be a difference in the year of the rigs.
My load readings are also similar to yours, but I can't remember what mine are at idle. They run from 50-70% going down the highway at 70 mph depeding on wind and terrain.
My load readings are also similar to yours, but I can't remember what mine are at idle. They run from 50-70% going down the highway at 70 mph depeding on wind and terrain.
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With my Autotap, it says about the same thing for my '01 that you're seeing for both the TPS and the calculated load.
I remember researching the "load" thing back when I got the Autotap for my '96 t-bird 4.6L, and lots of people were highly upset that they couldn't get a realistic number for almost any vehicle (including 'vettes). Of course, they were never promised a realistic number in the first place, never having been told they could even GET a calculated load value, but I digress
I remember researching the "load" thing back when I got the Autotap for my '96 t-bird 4.6L, and lots of people were highly upset that they couldn't get a realistic number for almost any vehicle (including 'vettes). Of course, they were never promised a realistic number in the first place, never having been told they could even GET a calculated load value, but I digress
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Thanks for the quick responses guys, I won't worry about the TPS/load. One last question, what should the O2 values typically look like? While running, they were both hovering around 0.9v, but what's odd is, when I shut off the engine, then turned the key back into the ON position (KOEO), one of the O2 values went to zero, and the other was showing around 0.8v. That doesn't seem right to me, but what do I know?
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Ok, well scratch that last question. I got the sensor screwed in most of the way (it's damn near impossible to get to so I'll have to take the alternator off to completely tighten it), and now the scan tool shows it gets all the way up to operating temp now, and goes into closed loop operation (before it was always in open loop, with the short-term correction at about 20% enrichenment), and now the O2 voltages are cycling back and forth between 0v and 1v rapidly like they should. It idles down to 800rpm now (used to always be at 1100rpm), and I did a couple warm restarts and it fired up immediately. Woohoo, problem solved! Oh, and after I took a closer look at the temp sensor, the threadlock/sealant on the threads looked like it was a brand new sensor that had never been screwed in! I'm guessing last time someone worked on the engine, they forgot to put the sensor back in, or couldn't find where it was supposed to screw in, or who knows... but in any case, I'm expecting it to pick up 1-2mpg easily!
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About the TPS readings....I have a Scan Guage II like Mmaxed. My idle reading (value) is 20. I just assumed it was a value assigned to whatever the thing was reading from from and not the actual percentage. I think this because at WOT it reads 92.
I extrapolated that each number from 20-92 was 1.38% of throttle. So when I was at a displayed value of 30, the actual percentage was 13.8%.
Am I thinking wrong?
I don't even pay attention to LOAD because I cannot understand how it derives the displayed value.
I extrapolated that each number from 20-92 was 1.38% of throttle. So when I was at a displayed value of 30, the actual percentage was 13.8%.
Am I thinking wrong?
I don't even pay attention to LOAD because I cannot understand how it derives the displayed value.
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Yeah, I just thought that this truck had been goofed-around with enough, and with the fast idle it was having, that maybe someone adjusted the idle position somehow. I think you're right though. The value is the % of 5 volts that the computer is getting from the TPS, and 20% is probably just where the TPS ended up at when the factory determined the idle position. The fact that it never gets to 100% is probably a good thing too, that way you know it's never trying to go over-range.
And as far as LOAD goes, I think it MAY be accurate... in that the value displayed is basically the % of torque the engine is capable of producing at that particular RPM (roughly)... so when you're cruising in OD at 1500RPM, and it says 50% load, that means youre using half the torque the V10 can produce at 1500RPM. My guess is that it is calculated by the duty cycle of the injectors... say on the map, max duty cycle at 1500RPM is 25%, and they are currently running at 12.5%, that means your load is 50%. I dunno, that's just a guess.
And as far as LOAD goes, I think it MAY be accurate... in that the value displayed is basically the % of torque the engine is capable of producing at that particular RPM (roughly)... so when you're cruising in OD at 1500RPM, and it says 50% load, that means youre using half the torque the V10 can produce at 1500RPM. My guess is that it is calculated by the duty cycle of the injectors... say on the map, max duty cycle at 1500RPM is 25%, and they are currently running at 12.5%, that means your load is 50%. I dunno, that's just a guess.
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