Water-related sputters

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2003 Mazda Protege5, manual
Hey folks

Gave Diana her first good clean since I got her yesterday at the local "Wash-all-you-want" including a good clean of her engine bay. Ended up turning out really nice to my pleasant surprise as all the dirt blew right off with a little encouragement from soap and a light pressure washer.

However. After finishing up the rest of the wash and letting the engine bay dry off much as it could, I went to start her up. No problems, then sputters and bogs. It won't respond to throttle input until I flutter it a few times and get up to about 2k rpm. By that point, I better get it in gear and senditt otherwise it tries to die.

The strange thing is that it only does it immediately after startup, cold or hot. Once I get it going, it drives perfectly fine and idles at stops and everything. Occasionally when starting from a stop up a hill, it'll try to bog down, but that's fixable if I just kick the gas to jump RPM before releasing the clutch.

All this to say: what do you guys think I got water in? I know that's the problem, but air intake is clear, all vacuum lines are clear and in tact, etc etc. Any ideas?
 
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protege5
Remove the coil packs and spark plug boots. You've probably got water in the spark plug holes, happened to me all the time driving down my road (I've got mud holes that appear after it rains that are about 10-15 feet long, 1+ feet deep and go across the entire road). Had to take the P5 and send it full throttle to make it across lol. Now I've sold the p5 and have 4x4 :)

While you're in there, it would be a good time to replace the plugs.
 
:
2003 Mazda Protege5, manual
Remove the coil packs and spark plug boots. You've probably got water in the spark plug holes, happened to me all the time driving down my road (I've got mud holes that appear after it rains that are about 10-15 feet long, 1+ feet deep and go across the entire road). Had to take the P5 and send it full throttle to make it across lol. Now I've sold the p5 and have 4x4 :)

While you're in there, it would be a good time to replace the plugs.
Cool! I'll give it a shot and see what happens. Thanks!
 
:
2003 Mazda Protege5, manual
Remove the coil packs and spark plug boots. You've probably got water in the spark plug holes, happened to me all the time driving down my road (I've got mud holes that appear after it rains that are about 10-15 feet long, 1+ feet deep and go across the entire road). Had to take the P5 and send it full throttle to make it across lol. Now I've sold the p5 and have 4x4 :)

While you're in there, it would be a good time to replace the plugs.
Welp. New wires/boots and new plugs since I'd been planning on doing it anyway. However, the problem is persisting. It's almost like a vacuum leak where it surges down from 750RPM then kicks up to 2k to recover before idling back down. Then it starts all over again. But the strangest thing is it doesn't do it after driving down the road. I'm in the Popeye's drive thru right now and I've been idling steady with AC on for 10 minutes.
 

pcb

The Diagram Dude
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2002 MP5
If you disconnected your battery, your ECU needs to relearn how to idle the car.
It takes about 100 miles of driving for the idle to stablize.
 
:
2003 Mazda Protege5, manual
If you disconnected your battery, your ECU needs to relearn how to idle the car.
It takes about 100 miles of driving for the idle to stablize.
Hmm... I didn't disconnect it beforehand, but I think I'll try doing that, see if it just needs to relearn now that it's clean for whatever reason. Lol wish me luck! We'll know in the AM
 

pcb

The Diagram Dude
:
2002 MP5
Keep in mind that it may run even worse.

Check the electrical connector to your IAC to see if it's wet or corroded.

Here's a couple diagrams.





See what happens with disconnecting the battery then maybe go for a long hot drive to dry out your engine.
 
:
2003 Mazda Protege5, manual
Keep in mind that it may run even worse.

Check the electrical connector to your IAC to see if it's wet or corroded.
It worked! I took the plug off the IAC and it didn't look corroded or wet. But I put some WD on the connector and the plug off the valve just in case. (WD-40 makes a great contact cleaner and short term dialectic) turned her on and boom! No more idle issues.

Thanks for the tips!
 

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