Fx50 throttle body nightmare

[Ashephillis]

I will start off by saying i have been a mechanic on the side for about 18 years and have tons of experience fixing all kinds of vehicles, so Here's my latest dilemma. I removed my intake tubes to install new plugs and in the process i noticed my throttles were a bit filthy, so i gentlymoved the throttle plates open by hand and cleaned them with intake cleaner and a soft brush. Afterwards car was idling high, i figured id need to do an idle air relearn. No big deal, I have a snap on verus pro (10k scan tool) with the latest software. No luck, test will no complete tired over 50 times. Ok, so i try the "pedal dance" those of you not familiar that is the manual way to do the throttle relearn, with a series of key on, key off procedures. No luck there either, tried probably 50 times.

I gave up and took it to the dealer, they couldn't even do the relearn with the consult 3 dealer software. So i came to terms with the fact i damaged my throttles, dealer quoted me about $1300 for them. So i sourced a used pair inline for $240, install them, annnnnd nothing. Still high idle, around 1200rpms , still will not relearn for anything. I know certain conditions have to be met for the test to complete, and all have been within spec.

At this point i dont know what to do, there is a chance that the used throttles i got are no good but its slim. I dont know if i should pony up 1300 for new oems or what. Maybe the ecm is fried? The car drives fine at speeds over 40, but stop and go traffic is not good.

This is bad when even the dealer is stumped. I refuse to let them just start throwing parts at it to try to fix it. Any ideas?

 

[ocal21]

Have you checked with other dealers close by? See how much others charge or even checking with a Nissan dealership?

 

[Ashephillis]

Went to nissan first, they couldnt do it, then went to infiniti and neither could they. I think im going to buy to new aftermarket tbs on ebay and drop it off at the dealer and let them figure it out. Im about to rip my hair out. This is crazy.

 

[onthemove]

 

[Spencerkey22]

I will start off by saying i have been a mechanic on the side for about 18 years and have tons of experience fixing all kinds of vehicles, so Here's my latest dilemma. I removed my intake tubes to install new plugs and in the process i noticed my throttles were a bit filthy, so i gentlymoved the throttle plates open by hand and cleaned them with intake cleaner and a soft brush. Afterwards car was idling high, i figured id need to do an idle air relearn. No big deal, I have a snap on verus pro (10k scan tool) with the latest software. No luck, test will no complete tired over 50 times. Ok, so i try the "pedal dance" those of you not familiar that is the manual way to do the throttle relearn, with a series of key on, key off procedures. No luck there either, tried probably 50 times.

I gave up and took it to the dealer, they couldn't even do the relearn with the consult 3 dealer software. So i came to terms with the fact i damaged my throttles, dealer quoted me about $1300 for them. So i sourced a used pair inline for $240, install them, annnnnd nothing. Still high idle, around 1200rpms , still will not relearn for anything. I know certain conditions have to be met for the test to complete, and all have been within spec.

At this point i dont know what to do, there is a chance that the used throttles i got are no good but its slim. I dont know if i should pony up 1300 for new oems or what. Maybe the ecm is fried? The car drives fine at speeds over 40, but stop and go traffic is not good.

This is bad when even the dealer is stumped. I refuse to let them just start throwing parts at it to try to fix it. Any ideas?

I had this same issue before. This my throttle bodies gave out a while back. Luckily my car died in the garage after i put it in park. After they replaced the throttle bodies it idled high like your describing. They installed/replaced the power steering switch and reprogramed the ECM. They said for some reason the power steering switch was the problem for the high idle after the throttle body swap. Hopefully this helps. If you need any thing else let me know. Good luck. Check the pictures below. You may have the same issue.

 

[Ashephillis]

I had this same issue before. This my throttle bodies gave out a while back. Luckily my car died in the garage after i put it in park. After they replaced the throttle bodies it idled high like your describing. They installed/replaced the power steering switch and reprogramed the ECM. They said for some reason the power steering switch was the problem for the high idle after the throttle body swap. Hopefully this helps. If you need any thing else let me know. Good luck. Check the pictures below. You may have the same issue.

What happened when your throttle bodies "gave out" ? Were you having issues with the power steering beforehand? Did you have Any lights on the dash? I wonder what pointed the tech to that? My car is going back to the dealer on Thursday. I appreciate your input a lot.

 

[Spencerkey22]

What happened when your throttle bodies "gave out" ? Were you having issues with the power steering beforehand? Did you have Any lights on the dash? I wonder what pointed the tech to that? My car is going back to the dealer on Thursday. I appreciate your input a lot.

Im not really sure. I drove it into the garage and put it into park and it just died on me. Wasnt really sure what happened. It would start up for 2 seconds and die. Had a tow truck pull it out of the garage and take it to the dealership. If you want to know the codes it gave me from the dealership i can provide them for you. I dont know why or how the tech figured it out. I think they sent out a infiniti tech specifically for my car since my dealership very very rarely has any fx50s come in but usually its only for small services. This was out of their league as far as i know from what the techs told me. Cuz since they had never done this type of repair on a fx50s only on fx35 and 37 they didnt know how to approach it. The infiniti tech they sent out some how knew it was the power steering switch that was causing the high idle. The regular dealership techs kept telling me they reset my ECM mulitple times and that it would need to be replaced. I requested they have a special tech sent out to observe the car because the answers they were giving me were like it may be this but we cant be for sure. I couldnt blame them but they happily got a infiniti trch out and he diagnoised the issue quickly and said most people wouldnt relate a power steering sensor with a high idle. So yeah thats about it. If you need the list of codes my car had at the time. I can give them to you. I have a folder with every maintenance/repair/tire replacement etc record stemming back from the first ever service of the car. Any repair or maintenance you can think of i have it in my records. I take my maintenace records very seriously. Its like a health record but for your car. Just have the techs at your dealership check the power steering sensor. Keep me updated and if its not the sensor ill try my best to help diagnose it with the info you provide me.

 

[CBRworm]

In the 350z/G35 forums, some people have dealt with this by disconnecting a fuel injector to get the idle down low enough for the relearn to complete, then reconnect the fuel injector (the idle will be higher, but probably lower than it was initially) and try the relearn again. Others will block part of the intakes or use other measures to get the idle down low enough for the ECU to start the relearn process. Apparently, it cannot compensate for the drastic rise due to cleaning. It is also possible that physical damage has been done by moving the butterflies by hand. Typically, people will turn the key to the run position and put something on the accel pedal to open them for cleaning. I'm not sure what the FX50 equivalent is - on the older cars with intelli-key, there is still a physical knob you can turn to run without starting the engine.

Of course, after this, you will need to clear the misfire codes.

 

[Ashephillis]

So I drove the car around for about2 weeks with the used throttles i bought, the car seemed to be idling good, so i figured I'd try the relearn with my snap on scan tool again and it actually worked. The car idles right at 650rpms with no codes. I have no idea why i couldn't get the relearn to take from the start but whatever it's fixed. Just thought I'd post an update. Moral of the story, do not touch your throttles. Period.

 

[Abdul Ardate]

So I drove the car around for about2 weeks with the used throttles i bought, the car seemed to be idling good, so i figured I'd try the relearn with my snap on scan tool again and it actually worked. The car idles right at 650rpms with no codes. I have no idea why i couldn't get the relearn to take from the start but whatever it's fixed. Just thought I'd post an update. Moral of the story, do not touch your throttles. Period.

I was going to clean my throttles but now I won't touch em. Sorry to hear about your troubles and im glad it's back to normal .thanks for sharing .

 

[WietseFX35]

A bit of an older thread, but thought i'll share anyway.
A while ago i felt the car hesitated a bit at some point from idle so during a regular oil change/service i decided to remove the throttle body's and give them a clean.
But soon after seeing the throttle bodies i realized these things probably will not enjoy disconnecting the electrics and/or touching the butterfly valve and open it by hand so i did not touch them.
Just blasted a can of carb spray from both ends until clean inside and left them to dry.
No need to remove them, just keep plenty rags below them to catch all the fluid and dirt.
After the car fired right up and run great, also the hesitation off idle was gone so it was a good clean up with good results.

In this case the power steering sensor gave problems, auxiliary equipment as power steering, A/C systems etc. tend to have a controller that increases engine rpm to provide a bit more power to prevent the engine from stalling, this is most likely the sensor that was giving you the problem.
Too bad it had ended up this expensive for you, all this electronics are sometimes very hard to diagnose.

 

[CBRworm]

This is probably a good plan. With other Nissan/Infinities, you can have the ignition on/engine off and press the gas pedal to open the throttle plates while you quickly clean the gunk off the TB and edges of the throttle plates without moving them with your fingers - but if they are really dirty you can still end up with too high of an idle for the re-learn to be easy.

 

[ariele]

I was going to clean my throttles but now I won't touch em. Sorry to hear about your troubles and im glad it's back to normal .thanks for sharing .

I removed, cleaned and re-installed my throttle's twice (i was aware to never moved throttle plates) without no issues. Once this cleaning fixed an RPM fluctuation problem