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Engine No voltage to TPS

  • Thread starter Thread starter 3054tony
  • Start date Start date Nov 13, 2023
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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
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#41
  • Dec 7, 2023
  • #41
3054tony said:
I'll pull them in the morning when i get some light and try to get a balance test but not sure if it will be able to. If I press the gas pedal down too fast it will die.
Click to expand...


You can feed it in moderately. I think the ECU just looks for >50% on the TPS sensor to run the CBT.
 
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3054tony

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#42
  • Dec 7, 2023
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Mustang5L5 said:
You can feed it in moderately. I think the ECU just looks for >50% on the TPS sensor to run the CBT.
Click to expand...
I'm probably doing something wrong but I can't get it to do a balance test. KOEO it's saying 11 for system ok then the 10 separation code and a 63 in the continuous memory for TP circuit fault, below minimum voltage. KOER test it will throw code 98 and 63.

Going to try and erase the 63 and try again.
 

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3054tony

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#43
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I erased code 63 and redid the test now it's backwards. It's showing 63 O and now 11 is in the continuous memory. KOER still the same with 98 and 63.

Still showing 5 volts to the orange and 1.00 to green on the TPS
 

General karthief

wonder how much it would cost to ship you a pair
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#44
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Stop jumping around, you will need to start at the idle adjustment, this is what I would do, now I'm not a jiffy ASC certified mechanic but once you get what does what with EFI it becomes clearer, this step will be done with the engine off, key off, back off the idle screw untill it's off the little arm, screw it in until it just touches the lever, about half/quarter turn in, this should open the butterfly enough to run, turn key on, check TPS, I believe .5 to 1. is acceptable, next check that the rotor points at or near to #1 plug wire when the balancer is at 0*-10* if you have not messed with the timing this is close enough, if you have moved (or removed) the distributor then you should check top dead center is relative to 0* on the balancer. This should get it started and run good enough to continue.
This is considering the plugs/wires/cap and rotor are good.
You also need to check ALL the vacuum lines, this stuff is old and crusty, you may need to pull the upper plenum to inspect all of them, several are underneath, check fuel pressure, you can borrow a FPG set at most O'Reilly Autozone parts stores.
Fiddling with too many adjustments and swapping parts is, in most cases, a waste of time and money. It also makes resolving issues more difficult.
If you need more info on what does what when and how to adjust things properly go to the 'surging idle checklist ' in the technical/how to threads.
 
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Mustang5L5

That is…until I whipped out my Bissell
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Dec 7, 2023
#45
  • Dec 7, 2023
  • #45
Code 63 is your TPS voltage is too low. That means the ECU is reading less than 0.5 volts.


I think you measured 0.9-1V at the TPS sensor, but you shoyld see what you have down at the ECU. With the ECU plugged in and key ON, backprobe pin 47 and 46. Pin 47 is the signal return from the TPS. What do you have here? If oyu have 1V at the sensor, but 0.2v at the ECU, you have a connection problem somewhere.

98 (r): Hard fault present. The PCM is running in FMEM (Failure Effects Management Mode). Something is messed up. I would troubleshoot the code 63 first before proceeding. That may be causing a hard fault (especially if that wire is shorted)
 
Last edited: Dec 7, 2023
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3054tony

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#46
  • Dec 7, 2023
  • #46
Mustang5L5 said:
Code 63 is your TPS voltage is too low. That means the ECU is reading less than 0.5 volts.


I think you measured 0.9-1V at the TPS sensor, but you shoyld see what you have down at the ECU. With the ECU plugged in and key ON, backprobe pin 47 and 46. Pin 47 is the signal return from the TPS. What do you have here? If oyu have 1V at the sensor, but 0.2v at the ECU, you have a connection problem somewhere.

98 (r): Hard fault present. The PCM is running in FMEM (Failure Effects Management Mode). Something is messed up. I would troubleshoot the code 63 first before proceeding. That may be causing a hard fault (especially if that wire is shorted)
Click to expand...
Ok so key on I'm getting .96 to tps and at pin 47 I'm getting .93. Pin 46 I'm getting nothing.

On an odd note the car seems to be running better all by itself? I was able to unplug the IAC and it didn't die so I did the base idle reset.

I'm just so confused but at least it seems to be running
 

Mustang5L5

That is…until I whipped out my Bissell
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#47
  • Dec 7, 2023
  • #47
Pin 46 is sensor ground. You actually want to measure the voltage between 46 and 46.


If it’s running better, dump codes again.
 
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3054tony

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#48
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Mustang5L5 said:
Pin 46 is sensor ground. You actually want to measure the voltage between 46 and 46.


If it’s running better, dump codes again.
Click to expand...
Ok gotcha, I did pin 47 and 60 for the reading. Will pull codes again
 

3054tony

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Mustang5L5 said:
Pin 46 is sensor ground. You actually want to measure the voltage between 46 and 46.


If it’s running better, dump codes again.
Click to expand...
Alright that worked. Koeo no codes just 11 and no memory codes
KOER CODES 33 for EGR not opening properly, 41&91 HEGO (HO2S) sensor signal out of range/always lean and HEGO (HO2S)sensor voltage low/system lean.

Balance test ran and came back with code 50. Assuming somethings wrong on cylinder 5
 

Mustang5L5

That is…until I whipped out my Bissell
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#50
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Yup. Cyl 5 not firing.

Test the injector. Measure resistance across the two prongs if you unplug the connector. Should be 14.4ohms of resistance.

Could also be spark and/or compression related. I assume the port is not blocked so air should be getting in.

Up to you to see which one you tackle first.
 
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3054tony

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#51
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Mustang5L5 said:
Yup. Cyl 5 not firing.

Test the injector. Measure resistance across the two prongs if you unplug the connector. Should be 14.4ohms of resistance.

Could also be spark and/or compression related. I assume the port is not blocked so air should be getting in.

Up to you to see which one you tackle first.
Click to expand...
That was the one I tested with the Noid light test when it wouldn't fire and it was getting power. Will try out the ohms. Wouldn't surprise me if it was the injector being all original

It's got new plugs, coil and wires.
 

3054tony

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#52
  • Dec 8, 2023
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Mustang5L5 said:
Yup. Cyl 5 not firing.

Test the injector. Measure resistance across the two prongs if you unplug the connector. Should be 14.4ohms of resistance.

Could also be spark and/or compression related. I assume the port is not blocked so air should be getting in.

Up to you to see which one you tackle first.
Click to expand...
I'm getting 14.3 then it will go to 14.2 but right back to 14.3
 

Mustang5L5

That is…until I whipped out my Bissell
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#53
  • Dec 8, 2023
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So that test comes back good.

But is injector firing? Usually i'd say swap the injectors and see if the problem follows the injector or remains. If oyu have a spare injector sitting around you can try that as well. The injector might be clogged internally.

I still wouldn't rule out spark and compression yet. I'd pull the plug, ground it somewhere and visually confirm a spark.
 

3054tony

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#54
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Mustang5L5 said:
So that test comes back good.

But is injector firing? Usually i'd say swap the injectors and see if the problem follows the injector or remains. If oyu have a spare injector sitting around you can try that as well. The injector might be clogged internally.

I still wouldn't rule out spark and compression yet. I'd pull the plug, ground it somewhere and visually confirm a spark.
Click to expand...
Pulled the plug and tested, it does have spark. I may have an extra injector laying around somewhere. If not it looks like auto zone has some in stock. In a wedding tomorrow so If I can't get there tonight after work I'll have to mess around with it Sunday
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,251
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Dec 8, 2023
#55
  • Dec 8, 2023
  • #55
You can always swap the injector to another location. A no-cost approach.

All depends on your gut feeling as to if that injector is bad or not.
 

3054tony

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#56
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Mustang5L5 said:
You can always swap the injector to another location. A no-cost approach.

All depends on your gut feeling as to if that injector is bad or not.
Click to expand...
Is there a way to swap 1 and 5 without taking the intake off? I'm supposed to be taking the car to storage for a few months while I move.

Debating on it since at least now it runs well enough to get on a trailer and store it Or pull the intake thats never been removed and probably cause another issue with my luck
 

limp

wrap a little cheese around it and its a done
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#57
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3054tony said:
Is there a way to swap 1 and 5 without taking the intake off? I'm supposed to be taking the car to storage for a few months while I move.

Debating on it since at least now it runs well enough to get on a trailer and store it Or pull the intake thats never been removed and probably cause another issue with my luck
Click to expand...
Personally, if you have alot on your plate right now, go stick the car in storage and get caught up on your move, new house, etc... When you bring the car home to work on it, you might have less on your mind and a clearer focus on the car......
Pretty sure most of the knowledgeable people on this site will still be here to help......
 
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