Hey all!

I have been looking on these boards for quite some time now and they are extremely helpful.

I ran into a problem with my Civic SI. When I start the car the rpm's are normal. After driving for a while and I stop the rpm's jump up to 1300 rpm's and drop back down and then jump back up. Eventually the rpm's build to 1500 when I stop the car.


When it gets to 1500rpms, when trying to shift into 1st the rpm's fluctuate making a strange sound. All gears also get very jerky. Have any of you experienced these symptoms before?


Brian

 

Sounds like you need to clean/replace your IACV. Its located on the back of you intake mani.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AddictiveAllMotor &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like you need to clean/replace your IACV. Its located on the back of you intake mani.</TD></TR></TABLE>

that, and/or a vacuum leak...

Other possibility, someone f'd with the idle adjust screw and now the IACV can't compensate...

 

Could the IACV get dirty? I got a quote for around 400 dollars for the valve. Does this sound like a common problem?

 

IACV most likely is the problem. Alot of threads has been created due to jump'n idles and alot of it is related to IACV being dirty or a leak.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00civicsiboy &raquo;</TD></TR><TR><TD CLASS="quote">Could the IACV get dirty? I got a quote for around 400 dollars for the valve. Does this sound like a common problem?</TD></TR></TABLE>

Yes they can get dirty. $400 sounds a little high though, I think I payed like $250 for one on my Type R. Before you go buy a new one try cleaning it with carb cleaner to see if that fixes first. Has your check engine light came on at all?

 

i had same problem jumped from 700-1500, i cleaned my iacv with carb cleaner 3-4 times, all that came out was black crap , ad then it worked great, try it

 

My CEL has not come on....Is it supposed to?

I am worried because I am a college student and I dont have the time or the money to deal with all of this...Hopefully it is something easy to fix...Someone also brought up a vacuum leak.. Could this explain why it doesnt do the symptoms when I start the car?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00civicsiboy &raquo;</TD></TR><TR><TD CLASS="quote">My CEL has not come on....Is it supposed to?

I am worried because I am a college student and I dont have the time or the money to deal with all of this...Hopefully it is something easy to fix...Someone also brought up a vacuum leak.. Could this explain why it doesnt do the symptoms when I start the car?</TD></TR></TABLE>

Mine came on but dont worry about that. Dont get all nervious about the situation, I drove my car like that for quite some time, it just gets annoying. I'm still going to put my money on the IACV more than a vacuum leak. Do a search here on HT on cleaning the IACV, its been covered a few times before.

 

your best bet is to try clean the IACV and if thats not it go from there. I doubt its a vacuum leak. Typically when you have a vacuum leak your idle is higher and just stays a bit higher than usual. Just look at all the rubber hoses that run to your intake manifold if there isnt any disconnected clean the IACV

 

IACV, take it off and clean it out and you're money.
i had the same problem and drove on it for a while till the CEL came on. i just took it off and cleaned it out and never had a problem since.

 

I don't really know how to explain what it does when trying to get into first gear. It sounds like it is the IACV. I checked the hoses and they are all good. I checked the undercarriage to make sure there wasnt a dent in the exhaust.

I am going to take the entire throttle body and the IACV out tomorrow and clean it with carb cleaner.

I searched for the way to clean, but didn't produce anything that is detailed..I am guessing just scrub a lot until it looks clean...

Any more input is always appreciated

 

removing the throttle body isn't necessary. If you do, make sure you get a new gasket.

remove the IACV and clean w/carb/intake cleaner. clean the mounting surfaces and check/clean the O ring. re-install...

start the engine

unplug the IACV and the idle should drop. You can also test the IACV by applying 12v and listening for a click...

 

haha good luck with that man. i had the same problem. everything was in good working order but still had that problem. that was the only thing i couldn't figure out. tryed everything, cleaning, new parts, vacumm leaks, coolant bleeding. nothing worked for me. but to help you out. the IACV is right behind the intake manifold. it has two bolts that should be 12mm and 2 coolant lines and a sensor plug. should be kinda roundish. hope that helps you locate it. i remember when i was asking people. everyone was like clean and change the IACV, but no one told me where it was. had to find it myself. but anyways good luck with that bro.

 

Perhaps I need to give in and take it to a Honda dealer...

 

vaccum leak or IACV

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00civicsiboy &raquo;</TD></TR><TR><TD CLASS="quote">Perhaps I need to give in and take it to a Honda dealer...</TD></TR></TABLE>

No need. Look on the back of the intake manifold there should be a round looking part that is bolted on by the throttle body. You will need to take out the 2 12mm bolts, unplug the wire harness and then remove the 2 coolant lines like was mentioned abvoe. Next just use some brake parts cleaner or carb cleaner (it is like 2-3 bucks a can at Autozone) just spray that on the 2 screens and the surface of the IACV just keep spraying now and then till it looks ralatively clean that is all there is to it. then just bolt and plug it back in and see if that solved your problem.

I tried to search for pics for you real quick while I am on break at work but it seems there are a lot of people asking how but no how tos have been done that I could find. Honda will charge you and *** load for doing very little here.

Edit: google search owns http://www.superhonda.com/foru...44463

 

Well I am also a member of the Hardforum and a member there said I could have coated the Map sensors with oil from the intake...Could this be a possibility?


Brian

 

have you checked your coolant level. Sometimes if the coolant is low, your idle will fluctuate.

 

Its not just the idle, its the fact that all of the gears get jerky and the 1st gear revving...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00civicsiboy &raquo;</TD></TR><TR><TD CLASS="quote">Its not just the idle, its the fact that all of the gears get jerky and the 1st gear revving...</TD></TR></TABLE>

If you have enough oil on your IM to effect your MAP sensor then you have MUCH larger issues.

Check out the IACV let us know if that fixes it. If not we can brainstorm what else it could be.

 

I will look and clean it tonight..Ralpie: I will let you know...Thanks

 

i had same symptoms but mine threw a cel for idle air control
i cleaned it w carbon buster

 

Well I would like to update you all:

I took the throttle body out today and cleaned it. It wasn't very dirty. While I was at it I replaced the throttle body gasket. I also cleaned the iacv valve and this also was not very dirty. I drove the car and still got the same symptoms as before. Does anyone else have any more ideas?

Could it be a vacuum leak even though it doesnt have these symptoms all of the time? What about the FPR?

 

I have the same problem i start the car early in the morning RPM is around 1500-1800 RPM... then as the car warms up the rpm just drop slowly and after it has fully warmed up the rpm drops to 0 or a little over 0 but yeah that's what happens to me.