I drove into town yesterday and my g37 would not accelerate past 2500rpm. After restarting, I was able to limp home and the check engine light had triggered. I pulled the P1233 ELECTRIC THROTTLE CONTROL FUNCTION code and disconnected the driver's air intake. I discovered a small piece of pink paper lodged in the throttle body valve and thought, WTF! When I opened the air box I discovered to my horror that the entire air filter had been shredded! Obviously some of the paper had been sucked into my engine so I removed the throttle body (being careful not to disconnect anything from it) and looked inside the plenum but could not see any debris. After vacuuming the air box and intake I replaced the filter and reassembled everything.

Now my engine won't idle properly. It hunts and settles at about 800rpm where it used to idle at 600rpm. Should I be worried or do I just need to perform an idle re-learn? Could there be paper stuck in my intake ports or vacuum lines?

Any advice would be appreciated.

Bryan.

 

Damn thats scary.....have you been driving it?

 

I drove about 70 km (45 mi) before discovering the problem. I drove it to work this morning and it pulled smoothly to 4500 rpm and seemed to be ok at highway speeds. As I said, the idle doesn't seem right. I also noticed that when I rev the engine, the engine stutters slightly as it drops past exactly 1500 rpm. Not sure if this is normal.

B.

 

Damn...someone needs to make a screen mod for the ram air intake portion to keep furry creatures out.

 

If you've inspected the TB's and they are clear of any more obstruction/debris, I'd say just go ahead and perform the idle air relearn. What have you got to lose? Most likely, you just got a piece that snagged and prevented the butterfly from fully closing when the ECU thought it should be closed and thus triggered the code.

I will also say that you're probably going to be OK in spite of the debris that undoubtedly passed through. It is quite amazing what can flow right through an engine without causing it any damage. Fortunately, the filter is 'soft' material.

You might also make a thorough inspection under your hood for any other possible rodent activity. Those little bastards can chew up wire and wreak havoc on your car.

 

I believe it's called a K&N ;^)
I'm not a huge fan of K&N since I no longer believe their claims of high flow rates (compared to paper filters) although filtration is superior. I had a K&N on my 2001 Maxima for 12 years without a single critter incident. I guess I'll have to bite the bullet and fork out the dough for a set of K&N's.

B.

 

Good advice. I inspected the engine compartment and all the wires look intact.

I solved my idle problem. On Sunday most parts stores were closed so I was only able to find one cheap filter. Yesterday I bought a pair of good quality Wix filters and now the idle is rock solid at 600rpm. Didn't even require a re-learn. There must have been an imbalance in air flow rates caused by having one old and one new (two different brands as well) filter which threw off the throttle calibration.

Bryan.