No Throttle response

[Thing30]

Car fired up ran fine without any issues. Next day my throttle actuator does not work. Hit the electronic gas pedal and the throttle bodies don’t respond. Replaced the actuator with new sensor and still have the same
Issue. Any ideas of problem? I’m going to run a diagnostic and see what codes I might have.

[nando]

well, there's 2 sensors in the pedal, one sensor in the actuator, and one sensor on the throttles themselves - if any one of these goes bad, it goes into limp mode.

[Thing30]

I replaced the sensor on pedal and sensor on actuator. The throttles are not cycling when the key is in ON position... starting to think my ECU is fried

[Thing30]

Haven’t ran a diagnostic yet. I’ve read though similar symptoms with batteries drained or receiving a jump could cause weird electronic glitches. From what I understand, if I were in Limp mode I should still get some throttle reaction, however in my case I get Zero throttle response and sometimes the car starts and sometimes it doesn’t. I should mention that the battery was currently receiving charge while we were starting it. Maybe it’s a battery issue... or I fried the ECU from starting it with a charging unit on? I don’t know

[rjmcdermott81]

Longshot but double check all your grounds for the swap wiring. Maybe something is loose.

[FredK]

There are four stages of limp home mode.

In the 3rd and 4th stages, the throttles are no longer activated, and the air going to the cylinder is actually metered by the idle control valve.

In the 3rd stage,

"The stage 3 emergency operation program is activated when the actual throttle position
exceeds the set throttle position for a defined period of time despite power being applied
to the EDR actuator, the throttle valves cannot be closed. The ECM reduces the amount of fuel injected (fade out) and retards the ignition timing to limit engine torque. If it is necessary to further reduce the torque, individual fuel injectors are deactivated one cylinder at the time."

And in the 4th stage,

"The stage 4 emergency operation program is always activated when an internal ECM fault is detected. In this case, the characteristics of the throttle valve control (EDR) are not predictable, therefore the ECM reduces the amount of fuel injected (fade out) and retards the ignition timing to limit engine torque. If it is necessary to further reduce the torque, individual fuel injectors are deactivated one cylinder at the time."

As nando mentioned, to operate properly the pedal sensors must be working, and both the sensor on the electronic throttle actuator (EDR) and the sensor on the throttle bodies themselves (at the front of the engine) must be functional. The training literature on the MSS54 also indicates that the adaptation values must be cleared when you replace the pedal or EDR angle sensor, otherwise it will continue to run in fail-safe (limp) mode. I'm not sure if you HAVE to reset the adapations, I think I did but I am not sure when I was chasing down a limp mode issue.

Leaving work one day my car had a 2750 rpm rev limit and I could not drive up even the most gentle of hills, so I had to do some digging on how to fix it.

If one of any of the three assemblies are bad, then you will have a limp home mode where the throttles do not activate at all. They will not move when you turn the key to the ON position. I got a new position sensor and a known-good used pedal and swapped the positions around until I got the car to activate the throttles again.

[nando]

the DME being damaged somehow is not impossible, but it's very unlikely. I've done some terrible things to these, and even seen one that was bent like a taco and other where the case was partially melted in a fire and they still worked just fine.

[Jim Lepage]

Are both your TPS ok ? First time I tried my pedal it wasn't working and it turned out to be the front one. I finally changed both, the other was crap too.

[Thing30]

What I pulled from the scanner last night

[Thing30]

Could the Alternator may be the issue causing the fault codes? Will be testing that. I also opened the ECU and did not find any corrosion or damage. Will update soon. Thanks

[nando]

Sure looks like a bad throttle pedal to me.

[Thing30]

So the car wasnÂ’t holding charge after start up, Alternator was faulty, however hasnÂ’t fixed the issue. I replaced the front TPS sensor. I believe I need to resync the throttles. DonÂ’t know what else to check. I would like to send the ECU out to get it checked, any recommendations

[dude8383]

Silly question but are you able to see live data on the pedal travel? Did you try another pedal?

[nando]

I still think it's your throttle pedal..

[Thing30]

I’ve already replaced the front sensor, Throttle Actuator with sensor and swapped pedals out. I’m waiting to get a OBD2 scanner back to see live data again. I’m stumped with what’s wrong. The battery is a couple years old, however it’s starting the car just fine. I would like to send ECU out for testing at this point. Any recommendations to test ECU out. Thanks