kato_si

Everytime I come to a stop or red light my car starts to shake when in Neutral. My rpm goes down low when this happends almost like it wants to shut off here is a pic .. what is the normal idle for it to sit at the rpm.

sleepyH22

should be roughly ~700rpms, looks like ur Si is idling at 250-300rpms.

kato_si

is there somethign i can do to fix the idle? suggestions

JustHere4ADay

timeing could be off... could be alot of stuff... sell your car to me

Dramier

There are number of things that could cause this...

Busted motor mount, stuck solenoid...

I would say it's probably not timing if it's running fine otherwise. Is this with the A/C on or off btw?

kato_si

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dramier &raquo;</TD></TR><TR><TD CLASS="quote">There are number of things that could cause this...

Busted motor mount, stuck solenoid...

I would say it's probably not timing if it's running fine otherwise. Is this with the A/C on or off btw?

</TD></TR></TABLE>

No A/c at all

hplssone

check idle air contol valve and wires take off and clean also vacuum lines especially brake booster to see if it has colapsed

Dramier

If the car does it while idling at a stop, i.e. where you can get out of the car, then here's a quick check you can do to see if the IACV is stuck..

Just take a small hard object like a hammer head or butt of a screwdriver and tap on the IACV.. if the idle jumps up or corrects itself, then the valve is sticking and you'll need to replace or clean it.

kato_si

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dramier &raquo;</TD></TR><TR><TD CLASS="quote">If the car does it while idling at a stop, i.e. where you can get out of the car, then here's a quick check you can do to see if the IACV is stuck..

Just take a small hard object like a hammer head or butt of a screwdriver and tap on the IACV.. if the idle jumps up or corrects itself, then the valve is sticking and you'll need to replace or clean it.

</TD></TR></TABLE>

Okay. Thanks. Umm can you or someone show me where the IACV is located? a picture will be nice

hplssone

on the back of the intake manifold has 2 coolant lines running to it and a plug should be black

phazedd

my car does that wen im low on gas lol

kato_si

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by phazedd &raquo;</TD></TR><TR><TD CLASS="quote">my car does that wen im low on gas lol</TD></TR></TABLE>
yea but mine shakes when the rpm goes low..

hplssone

why dont you pull the plug on your tank and see what comes out it sounds different from this guys problem

riceforlife

What would failing motor mounts have to do with a bad idle?

Dramier

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by riceforlife &raquo;</TD></TR><TR><TD CLASS="quote">What would failing motor mounts have to do with a bad idle?</TD></TR></TABLE>

Broken motor mounts don't hold the motor securely in place, and as it is idling, the vibrations from the motor will cause it to shake and vibrate. That shaking and vibrating will carry through the frame and you'll feel it in the dash and steering wheel and possibly the whole car depending on the situation.

Haven't you ever been in an older Accord that the dash shakes in at idle?

riceforlife

Oh yeah i see what you mean with the vibrating. I thought you meant... bad motor mounts = low idle rpms.

PHiNaTiK213

My old Si used to have that same problem but, sometimes the RPM would go up and down, ended up being a bad MAP sensor, i'd check that just to make sure

PinoyDelSol

I had a ripped driver side mount on my 97 civic coupe and when i was at a traffic light my ideal would also do that and bogg down quick. After i replaced the ripped mount my cars idle was good agian. Your best best is the mount. Check to see if you have some kind of grease or oil splashed somewhere on your hood or your cars chassis. Or if anything else just try everyone elses inputs, good luck.

kato_si

Dont think is the MAP sensor just replaced a few months ago but i have a feeling it might be the mounts. Thanks for the suggestions.

sk8shorty012

iTrader: (3)

when was the last time you had a valve adjustment? This can play an enormous role in how rough / smooth the idle is (as well as low RPM idles)

kato_si

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sk8shorty012 &raquo;</TD></TR><TR><TD CLASS="quote">when was the last time you had a valve adjustment? This can play an enormous role in how rough / smooth the idle is (as well as low RPM idles)</TD></TR></TABLE>

I have not well i bough this car in may of this year all i have done to it was a tune up. came already with i/h/e.. also noticed that if im at a stop/red light and i turn my steering while all the way to the right or left it will start shaking cause the rpm goes down... so it could be the mount/s?

hplssone

If the car was only vibrating I would go along with the motor mount thing, but you have a really low idle. This is probably a vacuum or iac valve problem. You wouldn't happen to have those gay colored vacuum hoses, because they are cheap and collapse. Try unplugging the iac valve and see if it makes a difference. If it doesn't that is your problem. If if it does then I would go with a vacuum leak. You can also try pushing the brake pedal to the floor and see if it makes a difference. Try pumping the pedal and see if it effects your idle. It will effect it some, but if it makes a dramatic difference it may be a collapsed vacuum line. Check the fat vacuum line that comes from the booster.

kato_si

also noticed when i hit the brakes and let go it jumps up to

adamrg85

start your car up and wait untill it is a normal running tempature and go under your hood and to the left of your map sensor there is flat head screw which is used to adjust idle, get a flat head screw and adjust the screw untill it is at normal idle. from what i seen most all cars vibrate when the idle is really low