Idling issues on my 2002 MP 5 (150 k) driving me nuts!
Had rough idle and private Mazda master tech mechanic suggested likely faulty IAC.
Bought new IAC (SMP brand aka Standard) for $125 (a steal I thought as most around $200 mark) plus new OEM gaskets for IAC & throttle body.
Got mechanic to fit all and asked him to clean throttle body during swap. Huge difference as idle stable and shaking/juddering gone. However on cold start it idles at just over 2000 rpm before gradually dropping to 700 in a few minutes. Mechanic suggested part faulty but he thought maybe could try adjusting it but I don't believe that part is adjustable? Can anyone confirm this (see photo for where he thinks is adjustable)? Company I bought part from says is not and agree to replace new one if I am sure it's faulty. Very reasonable of them.
Today had old IAC refitted and it's juddering again but does not start out at ridiculously high idle so I have confirmation new part was faulty. I read another blog on here about faulty new IAC's causing high idle so before I return it does anyone have any input about using SMP IAC's? OEM one's are almost $400 so not doing that.
Since the initial swap I now have a pulsing RPM issue during coasting. When hits 1100 it surges up to 1800 and then pulses sharply back & forth between the two. I wondered if new part caused that as never had before but now old IAC back it still does it so obviously not that. From what I've read could be vacuum line leak caused during part swap but my mechanical knowledge is sadly lacking so maybe someone else had similar issue?
Had rough idle and private Mazda master tech mechanic suggested likely faulty IAC.
Bought new IAC (SMP brand aka Standard) for $125 (a steal I thought as most around $200 mark) plus new OEM gaskets for IAC & throttle body.
Got mechanic to fit all and asked him to clean throttle body during swap. Huge difference as idle stable and shaking/juddering gone. However on cold start it idles at just over 2000 rpm before gradually dropping to 700 in a few minutes. Mechanic suggested part faulty but he thought maybe could try adjusting it but I don't believe that part is adjustable? Can anyone confirm this (see photo for where he thinks is adjustable)? Company I bought part from says is not and agree to replace new one if I am sure it's faulty. Very reasonable of them.
Today had old IAC refitted and it's juddering again but does not start out at ridiculously high idle so I have confirmation new part was faulty. I read another blog on here about faulty new IAC's causing high idle so before I return it does anyone have any input about using SMP IAC's? OEM one's are almost $400 so not doing that.
Since the initial swap I now have a pulsing RPM issue during coasting. When hits 1100 it surges up to 1800 and then pulses sharply back & forth between the two. I wondered if new part caused that as never had before but now old IAC back it still does it so obviously not that. From what I've read could be vacuum line leak caused during part swap but my mechanical knowledge is sadly lacking so maybe someone else had similar issue?
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