p0120 Throttle Body Code Keeps Recurring After Cleaning

If you drive only on the street a K&N is not all that bad. I'd never take my truck off road with one. And if it's over oiled it can foul up the MAF, gets is oily & attracts dirt easier. "High flow" filters don't filter that well & even with a stock filter particles can still get through. My truck came with a K&N FIPK. I sold it & put a stock intake on. The stock airbox I got did come with a K&N drop in which I do use for daily street driving.

All that black gunk that builds up inside the TB & intake manifold mostly comes from the PCV system. And if your engine is old & tired the more blow by it will have & the quicker you get that oily build up.

The TPS isn't in direct contact with intake air. All it does is measure the throttle position & is mounted on the outside of the TB. It can't get gunked up from the intake. It shouldn't need to be cleaned. I'm not sure what TB cleaner actually is these days but if I needed to clean a TPS for some reason I would use eletrical contact cleaner. I'm assuming TB cleaner is just some sort of sensor & plastic safe form of carb or brake cleaner, hopefully it is & I suppose that would do.

 

Yeah, I don't know. Like I said it was just barely dusty looking, but even after the throttle body was cleaned I was still getting P0120 code. It wasn't until I cleaned the TPS that the code went away. Isn't there a small rod and hole that the TPS connects to that makes sure the fly wheel (terminology) is closing properly? Maybe dust entered through there?

 

Lots of great info there. Thank you for sharing. I've heard aftermarket intakes aren't the best, and it definitely seems that the "high flow" filter cone that is on there isn't doing a great job. Can only imagine what it is letting into the manifold. I just opted to replace my TPS since I tried a cleaning of the TB and the IAC (w/o knowing it was called that). I'm now about to replace an O2 sensor (not sure if it is upstream or downstream) because of a P0420 code. Fun fun. Nonetheless, I bought an older analogue truck so I could do more of the work myself.

 

Update: the P120 code came back a few months after the cleaning. After trying everything, I guess its just time to replace the TPS.

 

It's surprising there's rarely any info in TPS threads about adjusting the sensor.

Mine will throw a p0120 for just about any voltage other than about 4.72-4.78 volts.

 

I'll check the voltage tomorrow. What to do if the voltage isn't correct?

 

Loosen the screws and turn the sensor. The mounting holes are elongated for this very thing.

 

I did my best to keep the old one in use. Voltage was good. It just wore out. New one fixed the problem. $42 genuine part.