Need some help! Rough start and idle.

[gallipd001]

Hey guys so I'm in need of some help. I drive a 2006 2.3L hatch and I've had some problems with it for about 5 days now. Basically every morning when I go to start it, she fires up first shot like a dream, but as I do a lot of short trips whenever I park the car and go back to it, the engine struggles to start once it is already warm. By the third time I start the car up it barely turns over. (seems like it only wants to start when the engine is cold and requiring lots of fuel).

Secondly, to contribute to the problem the car has been idling rough,RPM's seem to bounce around a bit

Third, there has been a bit of lack in performance. I rarely floor the car but now if you really pull it in first and second it seems sluggish. Not a huge difference in HP but when you drive your car everyday you know when something is off.

I can confirm its not the battery, starter and/or alternator as they are all working up to par and the battery is brand new. Today I tossed in a bottle of fuel injector cleaner with hopes that may work. Does anyone have any idea?! Hope you guys can help.

**sorry just to add, currently not showing any check engine lights though

[Shawn]

I would get the Battery checked again. Short trips under 15 minutes, do not get the battery charged back up.
New battery should be able to handle this for awhile.

[gallipd001]

Battery is brand new. put it on sunday with hopes it would take care of it and it didn't do the trick.

[peterm15]

How do you know the alt is fine.

Double check all your connections from your alternator. It sounds like an alt problem to me. Seems to be "jolting" rather then sending a constant current.

I don't know if I'm using the correct lingo or not but that doesnt matter. If you have a volt meter check the alt.

[Impressive]

Do you have an intake or any performance mods to the car?

[Kiyomi]

change and use full synthetic oil?

[aris]

You said you added a fuel injection cleaner? After you put that in you should take the car on the 401 and go on a road trip


change and use full synthetic oil?


Synthetic oil will not help him

[Kiyomi]

regular oil changes will keep an engine healthy.

[gallipd001]

there are no current engine mods done to the car and i do my oil changes as scheduled, never a day late. I ran the cleaner and went on about a half hour highway ride. Tomorrow morning I will be doing all highway as well so that should be able to go through the system quite well. What puzzles me the most is why it is sluggish in performance and why when the engine is relatively warm it struggles to turn over. The alternator and starter have been tested and are working as they should.

[Kiyomi]

moisture in the gas tank>?

[aris]

If it still Has a rough idle tomorrow I would add another fuel injector cleaner.... Since your car takes short trips it might be really dirty... That and the new fuel injection cleaners come concerted... Which means smaller bottles

[gallipd001]

If it still Has a rough idle tomorrow I would add another fuel injector cleaner.... Since your car takes short trips it might be really dirty... That and the new fuel injection cleaners come concerted... Which means smaller bottles

I think that is exactly what I am going to do - might even run it with 94 and see if that works. I'm running out of ideas. If this doesn't work maybe clean the throttle body? thoughts?

[Impressive]

I think that is exactly what I am going to do - might even run it with 94 and see if that works. I'm running out of ideas. If this doesn't work maybe clean the throttle body? thoughts?

If this works please let us know...I'd be interested in doing this to my car as well.

[aris]

I think that is exactly what I am going to do - might even run it with 94 and see if that works. I'm running out of ideas. If this doesn't work maybe clean the throttle body? thoughts?
Another thing I forgot to mention is how is the spark plugs? Have you checked them?

[TheMAN]

sounds like a failing fuel pump... you should have the fuel pressure checked

[Sonic31]

Cleaning the throttle body may help out the rough idle.

Also running a ground from the throttle body to the battery negative may smooth out the acceleration a bit.

[gallipd001]

Spark plugs are in good shape. Plus the car is only at 60k and they should last until 120k. Has anyone ever cleaned the throttle body on their own before? I heard some talk that the computer needs to be reset after the clean. Is this true/necessary?

[aris]

You will not need to reset your computer after cleaning throttle body..

[gallipd001]

sounds like a failing fuel pump... you should have the fuel pressure checked

I have had quite a few people tell me that so far - once i clean the throttle body I will have to look into getting the pressure checked.

[stock3]

Since you do lots of short trips your EGR may be clogged and sticking open, this usually causes hard hot starts. Cleaning the throttle body will not hurt as well, it probably needs it anyway.

What I would do is double dose a good fuel injector cleaner like Red Line, drive the car for at least 30 mins to make sure the oil is fully warmed up, take it on some isolated road with not much traffic, and do some high rev, WOT accelerations in second and third gear. Or just go on the highway and stay in forth gear for 10-20 minutes. That should clear things up quite a bit.

[gallipd001]

Is there anyway to clean the EGR? or is that something mazda would have to do?

[gallipd001]

So just an update: After running the fuel injector cleaner and ultra 94 the car seems to be back up to par. Just to be on the safe side I am still going to clean the throttle body this weekend

[aris]

So just an update: After running the fuel injector cleaner and ultra 94 the car seems to be back up to par. Just to be on the safe side I am still going to clean the throttle body this weekend

Good to hear the car is running better

[krimsalt]

Interestingly, the plugs seem to get fouled if u start the car for short periods of time. but that happens if you run the car for 15 seconds and shut it off, so it can't be that. But constant starting and restopping may cause an issue with your fuel injectors, so that is plausible.
I just bought my mz3 and noticed horrible fuel consumption until i put in a bottle of injector cleaner, it seems they can get easily fouled

[stock3]

That's why I recommend "Italian tune up" every once in a while. Short trips can mess up any of the emission components and some of them will not be fixed by fuel injector cleaners or hard driving. If you do short trips all the time, make sure that about once a week the car is driven for at least 20-30 minutes to bring everything to operating temperatures. The extra cost of fuel will pale in comparison to replacing the EGR valve, O2 sensor or catalytic converter. Take a joy ride every once in a while.

[TheMAN]

"driven for at least 20-30 minutes" is not an italian tune up! :rolleyes
you have to drive it like you stole it ON TOP of the 20-30 minutes