IAC cleaning... varying idle

pawel_r

Member
:
93 Mazda Protege Lx
i have a 93 protege 1.8l sohc automatic

for a while now ive been having issues with idle speed and rough idle/vibration

my idle speed is within spec right about 750 when i am in gear, but in park and neutral it goes up to 1250-1500

when i am within the spec rpm my car vibrates.. steering wheel, doors, dash.. look under the hood u can see the engine shaking around a bit.. but its not the mounts they were all done


i want to do some little cheap things myself before spending any more money on this problem.. one thing i was suggested is to check and clean the egr on my car

tho it doesnt have an egr.. but i believe it has an IAC valve.. could someone post instructions on what to do to take that off and how to clean it.


i heard this is a problem common on 1st gen automatics.. that is what the dealership tell me but they are AHOLES im sure a few little things like this and i can take away the prob
 
bump !!

my car is embarassingly loud when i put into park or neutral.. goes up 400ish rpms.. been driving it like that for 500km now but gettin worried it could make probs


note : adjusting the idle speed screw on top of throttle body doesnt work.. its in as far as it can go and wont go down from 750 in gear.. 1000-1500 in park..

there is another screw on there that is all the way down it can go too.
 
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bump BUMP!!

cmon somebody with a 1st gen.. im sure u have had these problems and could help me with some advice and instructions of simple things i could do myself.. cuz this car is worth maybe 1000 at most not worth taking it to the shop again i spent 200 on new mounts and a tuneup already..
 
same issue

I'm having the same issues on my 98 - its a 1.8 DOHC, when I hit the clutch it'll either drop to 200-300 rpm or to 1200-1500 rpm, just varies. was told IAC as well, autozone quotes $300
 
Just pull it off & clean it out with carb cleaner. On the 2.0 it's on the throttle body. It has star tool screws. Gotta be similar
 
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