Idle Problems

[imported_DIYperformance]

Hey CL, I finally had a few days off of work to drop in my b16 to a 96 dx coupe. But I'm having an idle problem. The car starts up and runs great, but once the engine has been running for a couple minutes, the rpm's will bounce between 1000 and 1500 in like a 2 second cycle repeatedly when idling. I was thinking that it might be coolant related because the car had to be warmed up first for it to happen. Also, the check engine light does NOT come on. Any suggestions?

[imported_Lacuna]

IAC sensor?

[imported_DIYperformance]

Do you mean intake air "temperature" sensor? or are you referring to the air intake control "valve"?

[imported_hersilvercivic]

hey i have an 88 civic lx and it does the same loopy idling, DIYPerformance.... both of those parts, the air tep. sensor and the air intake control valve are pretty spendy, my friend is a mechanic and he unplugged my sensor, so it doesn't idle loopy and irratic like that... he said it wouldn't fuck my car up and i trust him. that would be a temp. solution. the air temp sensor is about 216.59 and the TA sensor is 48.78, i called the dealership and found out. anyhow, hopefully some of this info will help you

[imported_biocac]

That air idle controller mentioned above will def. effect the way your idle behaves. A new one through most parts stores should run you about 60 bux in case you should have to replace it.
If you do it's plug and play.

Sam -

[simplegreen]

anyone's swap not do that when they started it up? mine did.. still does a little between 700-900

[imported_team_adrenaline]

It could also be the TB gasket, a vaccuum leak, either sensor, or a coolant problem. Before spending any money at all make sure that all the vaccuum lines are connected correctly and securely, then go from there. Unplug each sensor seperately and if it stops with one unplugged then that's the prob.

[imported_DIYperformance]

Okay, first off, I replaced the TPS sensor, because the one I had was physically damaged, but it didn't cure the problem.
I did unplug the IAC valve, but only to test it. If I remember, when you unplug it your CEL comes on, which would keep you in limp mode (no Vtec). But I also did clean out the valve with carb cleaner after it tested okay, still no luck.

I also did check all gaskets and vaccum lines, but had no luck there either. And I guess JDM's dont use EGR valves? Cause if it sticks open, that could also cause poor idle, because it would act like a vaccum leak.

So now, I've hopefully got it down to 2 issues.
1. I can always smell fuel, especially heavy at idle, so I know I'm running way too rich, plus I have to refill my gas at 250miles. If you are running extremely rich, it can screw up your ignition process (not the components), basically flooding the spark plugs or something, which can cause a crappy idle.

OR
2. I brought the car down to my friends shop to discharge the AC compressor so I can put the new one in (you know, the one that fits!). While it was there, we hooked up an OBD2 scanner, a real high tech ass machine like a little laptop, and it COULD NOT talk to the car. (???)

So I'm going to do a continuity test to make sure that the OBD plug under the dash is getting to the computer okay, and I'm going to plug in my old DX computer after the car has warmed up to see if the idle corrects itself, which would narrow it down to a wiring or ecu problem.

[imported_Vodoo48]

I have a '93 Civic, non v-tec, stock 1.5 engine, cirlce track car that does the same thing. I have no clue either about what it means. My buddy said it could be the distributor, but that sounds dumb.

[imported_DRAGNFARTPIPE]

YEA.. have you replaced the throttle body gasket yet? keep it simple stupid first things first