5/16 MD Plenum Spacer Installed. Having Idling Problems...
If its the MAF, I have the feeling is probably more related to the MAF housing or a related change in its calibration.
Kind of like how a popcharger can cause stalling even when its newly installed.
Kind of like how a popcharger can cause stalling even when its newly installed.
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From: Down Under & Dirty
On another note, I figured out why my ARC induction box kept rattling. It was the filter making slight contact with the upper induction box panel. The engines vibration caused it to rattle.
Just read the thread and I FEEL YOUR PAIN!!! I took my Z the get headers installed at some muffler/exhaust shop and when they were done hours later, I went to pick it up. They told me that when I started my car I needed to gas it a little bit so my car doesn't die. I left with that knowledge and after about a month or so, the problem stopped. It would idle high when I first started the car in the morning and drop to normal. Well anyway, I recently reset my ECU and the same problem is now reoccurring. I can't start the car and let off the accelerator without the car shutting off and when I do gas it to keep the car on, I have a VERY irregular idle (similar to yours I'm assuming). When I'm driving and I throw it into neutral, it will decelerate until almost stalling and climb back to normal again. Or when I simply have the car on and give it a little gas, the same problem occurs. I'm gonna try all of the things these guys were saying and see what happens. I have a CAI as well and I'm gonna get rid of it to see where I stand afterward. Good luck with it brother. I'm getting a plenum spacer soon so I hope I don't experience the same problems.
Based on your descriptions in page 2 and 3 of this thread I'm thinking its either the throttle body or MAF sensor.
1) The 2003 throttle bodies have a TSB out on them for this problem. You have a 2003.
2) You have a CAI. They are less likely to cause this specific symptom but it still can.
Without some way of eliminating what the potential cause is we won't be able to know for sure what the source is. Without knowing what the problem is, it will be difficult to fix.
As far as a correlation between idle being detrimental, I would generally say no, but without knowing what the problem is... I can't say if it is or isn't.
Trouble shooting the MAF sensor or throttlebody or spacer is the only way to find out.
And its possible it may not be any of the above. There are a number of potential causes.
It could even be the crank position sensor... but we won't know without a trouble shoot process.
1) The 2003 throttle bodies have a TSB out on them for this problem. You have a 2003.
2) You have a CAI. They are less likely to cause this specific symptom but it still can.
Without some way of eliminating what the potential cause is we won't be able to know for sure what the source is. Without knowing what the problem is, it will be difficult to fix.
As far as a correlation between idle being detrimental, I would generally say no, but without knowing what the problem is... I can't say if it is or isn't.
Trouble shooting the MAF sensor or throttlebody or spacer is the only way to find out.
And its possible it may not be any of the above. There are a number of potential causes.
It could even be the crank position sensor... but we won't know without a trouble shoot process.
The only common link is my throttle body. I don't want to drop 100$ something on a throttle body and it not be the cause though.
interesting. well do you remember what they check to tell if it's bad? like i said i can't throw around money on something if i don't know if it will fix it. I'm on a budget while in med school.
No. I only heard about the TSB being an issue.
I would say you could take it to the dealership for a diagnostic but sometimes they won't even do that if you have FI. It won't hurt to try though.
I would say you could take it to the dealership for a diagnostic but sometimes they won't even do that if you have FI. It won't hurt to try though.
Plus the bad part of my motor being down due to head gasket so i have to fix that first. Just hoping to kill 2 birds with 1 stone when i have it all apart.
If you can't take it to the dealership, you're going to need to find a mechanic that knows the 350Z really well. ...and a consult II.
Or you could try swapping throttlebodies with a friend who also has a 350Z or G35. If the problem goes away when you switch throttlebodies, you've isolated the root cause and the fix is easy.
Or you could try swapping throttlebodies with a friend who also has a 350Z or G35. If the problem goes away when you switch throttlebodies, you've isolated the root cause and the fix is easy.
If you can't take it to the dealership, you're going to need to find a mechanic that knows the 350Z really well. ...and a consult II.
Or you could try swapping throttlebodies with a friend who also has a 350Z or G35. If the problem goes away when you switch throttlebodies, you've isolated the root cause and the fix is easy.
Or you could try swapping throttlebodies with a friend who also has a 350Z or G35. If the problem goes away when you switch throttlebodies, you've isolated the root cause and the fix is easy.
i keed i keed.....i'll have to find a TB to swap and see if that changes anything.
I know it has nothing to do with my FI because i had the FI off the car when i got it out of the garage this spring before i took it to hte tuner. It still did this reguardless of FI or not.
hmm, is it bad if you don't disconnect the battery? I don't ever remember disconnecting it before when i've worked on the plenum. Maybe that's what killed mine.
Idle is great Tony. It only happens when I'm coming to a stop and let off of the accelerator. Or let's say I were sitting in my driveway, waited for the car to reach operating temp, then reved the engine. If I reved it, then pulled my foot off the accelerator. The car will boggle down and almost shut off, then regain smooth idle...
If you unplug the TB when the ECU is still monitoring, it will likely throw off the calibration.
i've done the relearn process a number of times. every time i take the plenum off i do it but if it damaged the TB then mine is done. lol
i can't wait to get home, tear the engine down, repair it, then test out a new TB....
if that fixes my problem i don't know if i'll be super happy or super pissed that i missed that for an entire year.
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From: Down Under & Dirty
just a thought. mine had the same symptoms after my install. i dont know if you ever took your TB off, but check the gaskets. during installing my copper TB coolant thing, the metal gasket slid down off the bolts and i didnt realize it. it was crooked and this caused a leak at the TB. i had the same exact symptoms....
Now if I could only figure out what's causing my ARC induction box to rattle at idle, I'd be a happy man...
