2003 M45 P1121 Code Issues. Need Help

[Mujtu]

I have a 2003 M45 Today Service Engine soon light came up. it's a steady light it's not blinking. So i go get the code checked up at Autozone. it pulled up P1121 which is linked to electric throttle control actuator. Should I try cleaning the Throttle or buy a new actuator. And how careful i have to be while cleaning the throttle up. The car jerks for 2 or 3 seconds when i crank it up in the morning but not really bad. haven't loss any power goes all the way to 70+ mph.
Help would be very appreciated

Thanks

[loystock]

Most likely, you have top replace the Throttle Body Assembly. But before doing so, check the air filter and replace if dirty. Then check the entire air intake, between filter and TB for any debris/restriction. Clean the MAF sensor (CRC MAF sensor cleaner will do). Check/clean the connector of the Throttle Position Sensor (TPS). Apply dielectric grease on the MAF and TPS connectors to prevent corrosion.

The drive-by-wire electric throttle control actuator has very sensitive components and Infniti does not recommend cleaning of the Throttle Body and Valve due to possibility of damage (DTC P050x). Also, the throttle body and plate have anti-gunk coating which when removed can cause high idling problems. If you have to clean the TB, it would be better to remove the throttle plate (butterfly valve, 2 mounting screws) and then use a rug to clean the TB and plate, NEVER SPRAY CARB CLEANER DIRECTLY INTO THE ASSEMBLY. Make sure the mounting screws are installed securely as they can get ingested by the engine when loose.

If all of the above fail, then you have to replace the Throttle Body Assembly (@ $500). Refer to the Factory Service Manual below for additional info about diagnostic (page EC-435) and TB replacement (page EC-437. YOu have to do several "Learning" procedures if the TB was replaced.

http://www.nicoclub.com/FSM/M/2003/ec.pdf

I'm talking from experience. I had my TB replaced, fortunately under warranty, in my 03Q45 (similar VK engine in M45).

[Mujtu]

Follow up
Thanks Loystock

I just got back from Advance auto parts. He ran a code it pulled P1121 but his machine gave a different description of the code. But i did change the Air filter as you said after that he re-stetted the code. the SES light has gone i have restarted it twice and the light hasn't comeback yet. I hope the SES light doesn't come back.. The Filter was pretty messed up.
What do you Think?


Thank You

[Romero2345]

Hey mujtu...

i had the same problem you had about 3 weeks ago...got the ses light...code 1121...looked at the air filter and it was filthy dirty...reset the code and came back on me a week later....my mechanic said it was my throttle body...went online and paid 467 (infiniti parts online) got the part on saturday..had my mechanic put it on monday and same day went to the infiniti dealer to get it programmed...have not got the ses light yet (2 days already) hopefully it wont come back...just alone this part broke my pockets this weekend...lol good luck

[Mujtu]

Thanks Romero.

I hope the SES light doesn't comeback. But I was thinking the same thing after few days it will comeback on. I did find remanufactured Throttle bodys online which are like $100 is it worth buying those if something goes wrong. And Advance auto it pulled same code 1121 but said MAF sensor issue. But online it shows throttle actuator. I'm gonna cross my fingers and hope it doesn't show up. How much did you pay for the relearn at the dealership. And what year and model is your car. Apparently lots of people have this same problem.

Thanks.

[Mujtu]

Romero just ignore the question about model and year. It says right besides your post. Didn't see it before.

[Romero2345]

Mujtu...the dealer charged me 120 plus tax..hope this helps..once again..good luck

[Mujtu]

Here's the latest update guys. I got my Throttle body assembly changed. I bought that assembly from eBay for $139.99 including shipping. It's remanufactured then I found my friend who is a mechanic at Lexus he is Lexus certified he changed it in 5 mins and I kept asking about relearning or rerogramming the computer he told me and convinced me not to go and get the relearn done at all. He said the car will learn it self he's like just drive as usual and the rpm might go up and down but nothing to worry about. So I just listened to him and being driving it with no rpm problem when it's idle I've already put 500+ miles on that throttle body and it has being a month the car is running perfect. Another trick he told me is don't put 5 quarts of oil he said that oil he very close to throttle body. Next time he said put 1/4 quatrain less so it has no room to sneak up throttle body.
Thank you very much for ya'lls help. Feel free to ask me any questions.