Solice

I have a '93 Civ Si that has a problem. It starts and runs fine for a little while, then, when I sit and idle, I notice that my rpms are really low, fall lower, and kick back up...low, lower, kick back up.....low, lower, kick back up....ect. Normal idle for my car before this was somewhere around 1300. A cold start puts it around 1500. Now, it barely gets 600. Every time I idle, this happens. My car seems to shake a bit more violently while at idle, and I feel less pull in the butt dyno because of this.

I've tried running fuel injector cleaner, but that didn't seem to have an effect. I've been told that if might be my O2 sensor, but I haven't changed it yet. Are there any other ideas?

I have a few mods, including a venom 400 chip, but the engine has been doing this since before I put any of the mods on.

Any help would be appreciated

00Red_SiR

Try cleaning your throttle body plate with some throttle body cleaner...that should fix it, if not you may need to clean your Idle air control valve which may have some carbon on it.

wilsel

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00Red_SiR &raquo;</TD></TR><TR><TD CLASS="quote">you may need to clean your Idle air control valve which may have some carbon on it.</TD></TR></TABLE>

Solice

I would try cleaning my throttle body, but it's brand new. The problem was there before that mod and is still present after(obviously).

Also, it wasn't my call to get a wider throttle body. My dad bought it, along with the venom 400 chip and a dc 4-1 header and had them all put on while I was out of the country this summer. Even though those mods were not on my 'planned mod' sheet, free performance parts are free performance parts.

So where is my idle air control valve, and how di I check/clean it?

00Red_SiR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Solice &raquo;</TD></TR><TR><TD CLASS="quote">I would try cleaning my throttle body, but it's brand new. The problem was there before that mod and is still present after(obviously).

Also, it wasn't my call to get a wider throttle body. My dad bought it, along with the venom 400 chip and a dc 4-1 header and had them all put on while I was out of the country this summer. Even though those mods were not on my 'planned mod' sheet, free performance parts are free performance parts.

So where is my idle air control valve, and how di I check/clean it?</TD></TR></TABLE>

It's part of your throttle body. Did your new throttle body come with all the sensors etc in it or did you switch them over to the new throttle body? Also when's the last time you checked your ignition timing?

Solice

I have no idea about the throttle body or the ignition timing. I try to do all the work on my car myself, but like I said, these parts got slapped on when I was out of the country. I've never seriously considered replacing my throttle body, so I've never taken a good look at it.

I've never checked my ignition timing. You think that might be part of the problem?

00Red_SiR

It could be especially since you said the rpms are below where they should be after the car warms up and that the car seems to lack accelerating power. Retarded ignition timing can do this and It's easy enough to check and rule out. So you're saying that when you were away, all those mods were done to your car but it still had the same problems even before they were done? Who did the work on it when you were gone?

Solice

A friend of my dad's. He's an older car kinda guy. He knows his stuff when it comes to older muscle cars, but I'm kinda leary about his knowledge of the newer ones. I have the feeling he treats my car the same way he would treat any car made in the late '60s, early '70s. It was that guy who gave my dad, who knows very little about cars, the idea of those three parts, header, throttle body, and chip.

My dad loves surprising people. He tries hard, but he never gets it quite right. I would have preffered the 4-2-1 stainless, skipped the chip and throttle, and gone with suspention, but, I wasn' around to control his outburst of generosity. But.... the parts are free to me, so I'm thankful.

00Red_SiR

Ok, but did you say the problem existed before your dads friend did work on the car? What kind of throttle body is it? could you ask your dads friend if he had to take the sensors off the old throttlebody and place them on the new one?

dogfood

I would say check your idle air control valve for buildup. Or you can just unplug it and see if that changes the idle fluctuation at all. It could also be a small vacuum leak, they can make your engine do some pretty funky things. Oh and it says you're from chesterfield, please tell me you are not in "the hatchett ridaz"

Solice

Oh but the Hatchett Rydaz is soo kew1!!!!!

No. I'm not with the Hatchett Ridas.

It's a 62mm BBK throttle body. I don't know about the sensors, but I'll try to find out.

How do I check these things, like the idle air control valve, ignition timing, and for a vacuum leak?

Thanks for the help guys. Keep it it.

TekSI

not sure how this would affect idle, but make sure the TB gasket is new. maybe there is a leak there?(please correct me if i'm wrong)

dogfood

The idle air control valve is either a three pin for automatics which would be attached to your throttle body, it will be green...Or if you have a manual it will be a two pin and will be on the back of your intake manifold(it will be black). Take it of and check if the screen is clogged or if anything is restricting the air flow. It is a long shot but it's worth a try. As far as the ignition timing goes you will need a timing light. And for the vacuum leak, If you can't hear it leaking, you can try carb cleaner, spray it around the manifold, vacuum lines, or throttle body, the idle will change if there is a vacuum leak. By the way, that's a nice throttle body, oh and the hatchett ridaz are great if you have an 89 dodge caravan with an apc sticker on the back.

Solice

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dogfood &raquo;</TD></TR><TR><TD CLASS="quote">By the way, that's a nice throttle body, oh and the hatchett ridaz are great if you have an 89 dodge caravan with an apc sticker on the back.</TD></TR></TABLE>

So you've seen my other whip then.....

I'll check that valve out. Not sure I can get a timing light anytime soon. I'm at school (MSU) so tools are hard to come by. Thanks a ton, man!

dogfood

If you need to check your ignition timing the next time you are back in town let me know, I have a timing light.

Solice

Thanks man, but I think the next time I'll be in town will be around thanksgiving. And then, probably not for a long time either. We'll see how it goes though. I'll IM ya' if the time comes.