Car has a “vaccum leak” somewhere in bank 1 that ive been chasing for a month now, ive pretty much threw every part at it (Tb,intake,hoses,pcv,coolant lines,etc…) it seems whenever that “leak” occurred so did the issue with the TB…i dont think a leak in B1 could cause the TB in B2 to act out?? Ive changed the TB that is making the weird noise 3 times!!.. (1st TB failed car went into limp, 2nd TBH and 3rd seemed to work normally up until a few minutes of installation the car warms up and it would make this “squeaky sound”) . Car is throwing code p0507 which I would think is the “vaccun leak in b1” which I inspected and have seen 0 leaks and have brought the car to 2 other mechanics WERE ALL STUMPED

 

For starters, are you using the OEM Hitachi throttle body or an aftermarket one?

I think the Hitachi part numbers are ETB0005 and ETB0008.

Have you thoroughly inspected the PCV vacuum lines and valve to make sure the hoses are all snug and the valve rattles?

Did you perform the throttle closed position recalibration and the idle air recalibration when installing the new throttle bodies?

 

Changed the TB with the OEM Hitachi ones , also ive changed the pcv valve and hoses there both new, also done all the relearn processes manually and with the scanner…HERE IS A VIDEO OF THE STRANGE TB NOISE

 

If the scanner supports that functionality then yes, it's definitely not something that happens automatically though. You would be commanding the throttle closed position calibration and idle air volume calibration by clicking separate functions. Idle air volume there's a lot of parameters that need to be met before this function would even be available, afaik the only software aside from Consult-III that has this functionality is Nissan Datascan 3.

Or you do the pedal dance method which is how it's typically done for all the recals.

Throttle closed position it's a lot easier to disconnect both intake tubes, then do the procedure twice while you visually inspect the throttle blade on each side for movement. The DE engine you can just listen for the throttle motor but the HR has two so it's better to visually check or use a mechanics stethoscope to make sure BOTH are working. Keep in mind this needs to be done anytime you unplug a throttle body. Idle air volume needs to be done anytime you replace a throttle body.

 

yes ive done the process 10000 times I understand you need to take the car for a spin, until operating temps,turn off power sources..radio,ac etc make sure the wheel is straight ive done it all, also yes ive used the Consult-lll to also do the relearn process ..nothing has changed I have an HR and I’ll include a video of the strange noise

 

Ok just got home so I could actually load that video, does it do that at all rpms or just at idle? Does it make sound if you go to drive or reverse, or does one of these gears make the sound while the other doesn't?

It almost sounds like something is rubbing and the sound is echoing around. Try just using your hand to push on the intake tube, throttle body, fuel lines behind the TB, etc to see if you can get it to stop.

Push the engine side-to-side with your hand at the intake plenum to try to rock the engine as well, that will put tension on the motor mounts, exhaust, etc.

Any change if you turn on the AC ?

I know this doesn't help with the DTC you're throwing but they might actually be separate issues. What rpm does the engine try to idle at once it's up to temp? Also that code doesn't mean bank1 or bank2, it's just saying that the target idle is too high which could be caused by ANY vacuum leak so make sure to troubleshoot both intake tubes and anything else that might cause a vacuum leak. Including the brake booster vacuum line.

If you stomp the throttle in park is it immediately responsive or does it feel a little laggy? This can be a little difficult to tell on the HR since you can have one TB working properly which is letting in a LOT of air while another one is laggy, engines that already breathe heavily are usually difficult to tell if a vacuum leak is present between the MAF and the intake valve unless it's a big leak. Especially since these computers are so responsive.

 

Okay so the noise does sound in park/ idle.. becomes wayy louder in drive. It not a gear issue it’s sounding in idling and drive, and does become more faster / louder as the RPMs go up as more air is being inducted.

Doesnt make a difference if the Ac is on or off, like ive said i have changed the TB 3 times , the last 2 times the sound went away , but as soon as the car warmed up to ( a few minutes after installing) it just went back to doing that sound…

Also the code p0507 isnt the code im talking about when i say there is a leak somewhere in B1 , thats just the most prominent code and only that comes up with my cheap scanner, when it was scanned with CONSULT-lll and a full diagnostic was ran thats when it was telling me there is a vaccum leak somewhere there….Also the car idles 1,000-1,300 when it use to be 600-800

Also to note that when I slightly press the car in PARK/ (2-3k rpms most) the car rpms would drop back to 1k and on its own move up to 1.5k as if i was still giving it some gas ..Also in PARK if I quickly press the brakes (continuously) the RPMS would shoot up to as if i was reving the car … ( I suspected the leak is causing all that)

Also the car is definitely a little laggy with the throttle response.. Today i will be conducting a smoke test as ive threw every part i could think off in B1 so my final option is to smoke the system

 

The smoke test will find it, but I have a feeling you'll be taking that plenum off. It might have a crack or somehow gotten damaged, might have a bolt that broke or came loose.

The drop in idle when trying to give it throttle is a pretty good indicator of a vacuum leak. You can disconnect the brake vacuum line right at the plenum and cap it off to see if there's a problem somewhere downstream. Same thing with the PCV hoses, disconnect from the intake tube and the intake plenum, use electrical tape to cap off those nipples. This will help isolate out peripheral stuff.

You can also disconnect the MAF sensors and remove the intake tubes completely. Then see if the noise is more pronounced from a specific area.

 

Hopefully the smoke test will find it , like i said ive threw every part at it.. I’ve replaced the plenum intake 3 times so its not that, ive changed every gasket 2 times , not that… we will see what happens today ill keep you updated

 

Do you happen to have the other codes it's thrown in the past?

 

soo good news … kinda feel dumb lol. So after throwing parts at it left and right and countless days scratching my damn head I figured out the squeek. So cylinder #2 coil wasnt fully inserted -.- , I pushed down the coil and the sound went away… this whole time im thinking its the TB but it was that coil right underneath that TB lol . Im glad its nothing major

 

I'm glad you got it fixed, nothing quite as frustrating as replacing parts on a car and having them NOT fix the issue.