throddle body test - Honda Prelude Forum

mparra11h22a · 12-06-2009, 10:18 AM

im having issues with my idle i have replaced the FIV and nothing i have no vacum leaks the car runs good its a 93 what should i do next? i have done the throddle body test u know the two holes inside the TB well when the car is idleing like bouncing when i put my finger on the top hole the idle stops and the car sounds perfect what does that mean a bad IACV? and the bottom hole the car does nothing plz help.

dharr67 · 03-30-2010, 03:50 PM

bump? i just did this test and plugging the upper hole fixed my idle, what does this mean, anyone?

Smoothrigoletto · 03-30-2010, 07:58 PM

hmm....what color is your radiator fluid? fully clean green or kind of green/brown? annoying Idling happened to me before and I cleaned out my IACV (esp where the water hoses passes through; the tube was corroded and totally blocked off by this rust brown color looking slime). I cleaned it and it did the trick.

njprelude87 · 08-09-2010, 05:35 PM

Did you ever find out what was wrong? i have the same problem, i plug the upper hole and it idles fine

jkoni426 · 08-10-2010, 10:03 AM

the upper port goes to the IACV i believe. the IACV prob just needs a cleaning.

dharr67 · 08-10-2010, 05:18 PM

I sold my car back in April and never figured it out. I cleaned the IACV twice haha and it still did it.

njprelude87 · 08-13-2010, 10:08 AM

yea, ive cleaned the IAC valve and have even swapped it from another throttle body with no luck. It must be a vacume leak from around the throttle body somwhere because ive checked all the lines for leaks and they looked good to me. Is there any other problem that could be causing these symptoms? Fast idle themo valve maybe?

I've gotten the check engine code - 14 Idle Air Control Valve Circuit Failure- once, but after i reset the ecu it didnt come back even after the car warmed up.

I've checked for voltage on the iac and it also looks good. im kinda running out of ideas here so any help would be appreciated

jkoni426 · 08-13-2010, 02:48 PM

it may be an intermittent (sp?) failure or it may take a few running cycles for the cel to kick back on. give it a few days, and if the cel comes back, download the service manual and troubleshoot:

SpoonerTuner.com - Free downloadable Honda Acura Factory Service Manuals by HELMS