Hello, I have a 2007 LR3 and I have an issue with the throttle signal. It seems to be reading around 15% when off throttle and up to around 100% on full throttle using my Autel to look at the data. I believe this is causing all kinds of rough running and no acceleration. I have replaced the throttle body and the pedal assembly already and it did get better but is currently at the above figures. I tried the relearn process a bunch of times, Ive checked the voltage at the pigtails and get ground and 5V correctly, and Im just kind of at a loss at this point. I just bought this car and have had the gauge cluster board resoldered, the PCM modules fixed that were burned out, Air shock, blower motor, a bunch of other things but this is the last really nagging issue that leaves it underivable. Thank in advance for your response.
2007 LR3 throttle signal
- Thread starter RS007
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One thing worth ruling out before you chase that number any further. On a lot of scan tools the throttle position PID is the absolute reading, and about 15 percent at closed throttle is actually normal, because the blade never rests fully shut. If your Autel shows a relative or corrected throttle PID as well, that one should sit near zero at idle. So the 15 to 100 sweep may be telling you the throttle side is fine.
If that checks out, I would put the effort into the rough running itself. Look at short and long term fuel trims and the MAF reading at idle, and check for vacuum leaks. After the work that engine has had, an unplugged or split hose would not be a surprise. Post the trim numbers if you can and we can go from there.
If that checks out, I would put the effort into the rough running itself. Look at short and long term fuel trims and the MAF reading at idle, and check for vacuum leaks. After the work that engine has had, an unplugged or split hose would not be a surprise. Post the trim numbers if you can and we can go from there.
The fuel trim for long term are 0 for bank 1 and -2.34 for bank 2. my maf is reading 22. short term fuel trim are both 0. the car is also in what I assume is hard limp mode. it will not rev past 1500 rpm. I am not getting a MAF code but I can replace. I am about to do a smoke test on vacuum lines but spraying brake parts cleaner did not yield any change. thank you for your response.
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Good numbers, and the screenshots actually tell the story. Trims sitting at flat zero, both O2 currents pinned at 1, and monitor completion stuck at 0 means the ECM is running open loop in failsafe. So stop chasing fueling, the MAF and vacuum side were never the problem.
The tell is your throttle position reading 24.71 with the pedal at rest while the pedal tracks read about 13 and 14. In electronic throttle failsafe the ECM cuts power to the throttle motor and the return spring parks the blade at a fixed limp home position, which reads right about where yours is sitting. The engine idles fast, ignores the pedal, and gets capped around 1500 rpm. That is exactly what you have.
Quick question first, is this the 4.4 V8 or the 4.0 V6? The path below is the same either way but it helps to know what we are looking at.
Two things to do next. First, pull codes from the engine module using the Land Rover specific section of your Autel, not the generic OBD screen. Failsafe like this almost always has throttle actuator or pedal correlation codes stored, P2101, P2104, P2110 or similar, and the generic screen can hide them. Post the full list including pending and history.
Second, key on engine off, watch or listen to the throttle body. On a healthy truck the ECM sweeps the blade once at key on, and if your Autel has an active test for the throttle actuator, run it while watching that TPS PID. If the blade never moves off 24.7, the ECM is not driving the motor at all. Then check the motor winding at the throttle body connector, it should read just a few ohms, and inspect the two motor wires back to the ECM.
And keep one thing high on the suspect list. You said the ECM was burned out and repaired. The throttle motor driver lives inside that ECM, and a repair that brought the truck back to life but left that driver circuit dead would produce exactly this. The relearn will also never complete while a throttle fault is active, so do not read anything into it failing.
You are closer than it feels. Get us that code list and the key on sweep result and we will pin it down.
The tell is your throttle position reading 24.71 with the pedal at rest while the pedal tracks read about 13 and 14. In electronic throttle failsafe the ECM cuts power to the throttle motor and the return spring parks the blade at a fixed limp home position, which reads right about where yours is sitting. The engine idles fast, ignores the pedal, and gets capped around 1500 rpm. That is exactly what you have.
Quick question first, is this the 4.4 V8 or the 4.0 V6? The path below is the same either way but it helps to know what we are looking at.
Two things to do next. First, pull codes from the engine module using the Land Rover specific section of your Autel, not the generic OBD screen. Failsafe like this almost always has throttle actuator or pedal correlation codes stored, P2101, P2104, P2110 or similar, and the generic screen can hide them. Post the full list including pending and history.
Second, key on engine off, watch or listen to the throttle body. On a healthy truck the ECM sweeps the blade once at key on, and if your Autel has an active test for the throttle actuator, run it while watching that TPS PID. If the blade never moves off 24.7, the ECM is not driving the motor at all. Then check the motor winding at the throttle body connector, it should read just a few ohms, and inspect the two motor wires back to the ECM.
And keep one thing high on the suspect list. You said the ECM was burned out and repaired. The throttle motor driver lives inside that ECM, and a repair that brought the truck back to life but left that driver circuit dead would produce exactly this. The relearn will also never complete while a throttle fault is active, so do not read anything into it failing.
You are closer than it feels. Get us that code list and the key on sweep result and we will pin it down.
My throttle body blade does not move. I figured this was the actual problem but am glad I ruled out fueling etc. I bench tested the throttle body and peddle actuator and they both test fine. I was basically down to tracing these wires and looking for a short. it does register a sweep if I press the throttle to 100 percent it just seems to be stuck thinking im on throttle when im not. IF you know the pinout of both I can read the voltage signal, im just not sure which is the correction to be reading. This is the 4.4 HSE and it's a 2007.
