The Usual 2000 rough Idle, Missing on 3 etc
 

Mazda MPV 2000 2.5 gas.
The codes are P0171, P0303, P0108, and P0705. The 705, probably just the switch. So far, replaced are IAC, plugs (autolite), plug wires and upper intake gasket. Cleaned the EGR, MAF and the throttle body by spraying carb cleaner into it. Checked hoses, PCV valve and hoses "look" good, and look to be replaced. Spraying carb cleaner on all the hose connections does not appear to affect idle. All connectors are attached. Computer has been reset. The rough idle still remains. When turned on cold, it runs fairly decent. After warm, rough idle and stumble most noticable about 1200-1800 rpm. I still think there may be a vacuum leak. As soon as the engine is off, the brake booster looses all vacuum...no residual vacuum at all. With the AC on, the brake booster loses vacuum occationaly. The main air intake hose is not cracked.
Could this be a bad valve on #3? That shouldn't affect residual vacuum after engine off should it? It seems to run fairly good abouve 2500rpm.
Thankyou, for your time and your help.
Keith

Hello Keith,

I've done the same things you've done to my 2000 MPV and I fixed my idle with a new set of wires. I agree that with the codes you've got it sounds like a vacuum leak. Maybe you've got a warped intake manifold? A shot of carb cleaner between the intakes might give a clue.

Good luck

Carl