I have started experiencing the problem other owners have had where my car would go into limp mode and disable the throttle (pressing the accellerator pedal wouldn't do anything). The code was P0121. So I did the first cheaper attempt at fixing the problem and bought a new throttle position sensor. Installed that today and noticed that I can get the car to stall when tapping the pedal when parked so I may need to adjust the sensor a bit. My OBD reader previously said that the absolute throttle position at idle was around 9% open. With the new throttle position sensor it is 6% open at idle now. While I was at it I also cleaned inside the throttle body (wasn't very dirty).

The main reason for the post is that after taking the car for a drive it went into limp mode again after less than 1 mile. Now the code I am getting is different than before, P1229 (looked online and it says electronic throttle control circuit). From reading some places online this code scares me (some places say it is bad ECM, which I'm sure is $$$$), other places online say it could be:

- bad throttle motor
- bad connection with throttle motor
- short in the wiring to throttle motor
- bad fuse or relay somewhere (haven't checked this yet either. I read online about R11 in relation to throttle?)

I have not checked any of the wiring voltages but I didn't see any problems with the connectors or wires near the throttle body. Did not check the other end of the wiring either (not sure where it goes, but I have read something about water pooling and causing wiring issues. From looking in the engine compartment I don't see any water or coolant, but I do know that my reservoir leaks very slowly). Also, could it be because the throttle position sensor is not adjusted right that would cause this P1229 code? (I don't think so myself)

At this point my next step was going to buy a throttle body for $300-$400.

I would like some opinions from others before I go ahead and do this.

 

sqenixs, having played with a throttlebody, it is sounding like the brushes inside your throttlebody are worn and they are not making good contact for the motor. This will cause the throttlebody to throw various codes. If you want info on pulling the throttlebody apart, let me know. It isn't necessarily hard, but it isn't for the average joe either. Once you get it apart, you can adjust a few springs to apply a little more force and all will be good. The hardest part of this is finding the penta-bit (yes, a 5 pointed torx bit) to get the throttlebody apart.

 

Yeah please provide me more information about adjusting the springs. I think I will go ahead and buy a throttle body anyway in case I mess things up, I can always return it if I'm able to resolve the issue. It sounds like you agree that the likely problem is with the throttle body and not the wiring or ECM, yes?

 

sqenixs, from my experience with the X-Type, as long as the connectors are good on the throttlebody, then the wiring is normally good.

As for pulling it apart, it is fairly straight forward. You are going to need the pentabit (T-20 as I recall, but it will be something really close to that) to pull the cover off of the side with the motor. From there, you will remove the gears for the drive. This will expose a few more bolts that are holding the motor to the throttlebody. At this point, you can remove the motor and you can then remove the rotor (center part of the motor). You will want to lift the rotor straight up to prevent any parts from falling out on you. Once you get the rotor out, you will see where the brushes set. On top of them, you will see little metal wires that push down on the brushes. You will want to tweak these metal springs so they tend to push down harder.

At this point, putting it back together is a real treat. You have to work on holding the brushes out of the way as you slide the rotor back into place. This is where most people have the biggest difficulty. Once you can get the rotor back into place, you can reinstall everything and put it back on the car.

Getting it apart isn't too bad. It is putting it back together that will push your limits.

 

Well my attempt at fixing the old throttle failed, so I just put the new one on. I bought a new one from a local guy for $300. Seems to have fixed the issue. So I think I actually had two problems, the first one was a bad throttle sensor, and the second one was a bad throttle motor. P0121 and P1229 were the codes. I did notice that the absolute throttle position at idle is 2%-4% open while my old one was closer to 10% open. Not sure if that matters. The car feels a little different when I step on the accelerator with the new throttle, that might be due to the positioning.