I installed a brand new Kinetix Velocity manifold on my Z today after running the V+ plenum for years with no issues, and now the car idles at between 1300-1500 rpm and occasionally the idle will start to creep up to 2000 rpm with no throttle input. I've checked for vacuum leaks and loose connectors but everything checks out. I've done the accelerator pedal position learning, throttle valve closed learning, and idle volume learning multiple times with no change, i also disconnected the battery to reset and no change. It is throwing the codes 0507, 0223, 0124, 0420. After the battery reset it only blinks slowly 3 times then stops then blinks slowly 2 times and goes back to continuous on. I've tried everything I can think of, so any help would be greatly appreciated.

 

Did you clean your Throttle body and mess with the plate by moving it with your hand or a rag? Is it connected properly to your wiring harness? Those are mostly throttle body codes.

Do a throttlebody relearn procedure. If that doesn't work maybe your throttle body needs replacing. But thus is just my guess

 

Were there any issues/codes thrown prior to you performing this intake swap? A lot of these codes piggyback off of one another with the originator suggesting a vacuum leak or irregular peaks/dips in voltage and/or voltage continuity to and from the throttle body.. Check the course of the wiring to your throttle body for any damage as a result of this intake swap(although unlikely if you were careful). It's also possible that you inadvertently fouled up the zero-point on the throttle body by moving/touching the butterfly valve; however, by you performing the throttle position relearn should've remedied this, if that was all that was wrong.. Assuming that all other avenues are covered, like vacuum leaks, throttle body wiring shortages and a throttle position relearn, I would then start addressing the throttle body itself along with the throttle position sensors.. It also wouldn't hurt to replace your throttle control motor relay located within the IPDM.

 

I did wipe the throttle body out with a rag but it was disconnected from the harness and i did the reset multiple times. I can hear the throttle body moving when doing the reset just as the write up says. I have checked the wiring and everything looks good, no stripped or cut wires. There were no codes prior to install. I cant hear any whistling or hissing that would be associated with a vacuum leak and throttle response is normal which would also indicate no vacuum leak......aside from the high/creeping idle. When free revving the car it revs up fine but as the revs are coming back down it hiccups at around 2000rpm and drops to 1000rpm for a second before returning to 1500rpm.

 

Ok. Did you get it tuned with the Kinetix V+ plenum on?.. Try cleaning your MAF sensor too... Maybe post a sound clip.

 

I'd put the v+ back on. I don't think there is any benefit from the velocity unless you're over like 5-600whp iirc or something high like that.

 

The car has never been tuned. I will clean the maf, but it was never taken loose durning install. I'm going to replace the throttle body if I cant get this figured out, I will try to get a video uploaded. I'm not going to put the V+ back on, I will be doing a custom turbo set up on the car this winter and the V+ had started to deteriorate at the bolt holes from heat (has been on the car for 9 years) so it was time for a replacement. I know the power gains N/A are negligible at best, but this issue isn't stemming from the velocity manifold. Replacing it with something else won't fix the problem.

 

But then I think, just swapping upper plenums wouldn't cause these issues.. It wouldn't hurt to try swapping the V+ back on to see if these issues remain. Because if they don't, there's no reason to go spend money on a new throttle body. But if the issues DO remain, replacing the throttle body would be justified...

 

Update, I believe now it is a throttle body issue. I can start the car and it will bounce between 1500 and 2000rpm, turn the key off and back on without letting the car die and it will hold idle at 1300.......a vacuum leak would be constant no matter what i did electronically. Tried to upload a video and video failed to upload.

 

When you cleaned the throttle bodies did you disconnect them or the ecu? I had a similar problem with my throttle bodies and found out I fried my ecu. It wouldn't relearn. My first recommendation would be buy a obd2 Bluetooth device, they are only like 20$. There are apps that do the relearn without the peddle procedure.

 

OK.. This might not be ''recommended'' but if done in a dust/wind free environment, a couple of minutes isn't going to hurt. Start the car and remove the intake tube where it connects to the throttle body and watch for the butterfly valve to open/close in correlation with the idle fluctuations... you'll probably get the CEL for the MAF, but it's ok for now.

 

Issue resolved........dont ask me how though. I got frustrated with the car and quit for a few, a buddy came by to help, I went back out and started the car to show him what it was doing........idled at 700rpm......no fluctuations, no hiccups, like the day I brought it home from the dealership. Car seems to be fine now, or my buddy has magical powers he doesnt know about lol. I appreciate all the help guys.

 

Ok we need to start cloning your buddy now..

 

Lol or he can just travel around the county to all Z owners houses for a small fee. Thanks again for all the help.

 

Lol Or that. No problem, bro. Nice engine bay btw