View Full Version : Idle prob & hess on accel...

03-26-2004, 01:08 AM
Anyone seen this problem before? 93 ex with stock engine (180,000mi.) warms up to normal operating temp. runs fine and unpredictably hesitates on acceleration. This is most prominent after coming to a traffic stop and rpm's. drop below 500 at idle. I know that the recommended idle rpm. range should be between (700-900), but can not figure out why it doesn't always stay in this range. After the rpm's. drop to about 500 and I try to accelerate it hesitates for a few seconds and runs normal again. I have already spent $1,200.00 on diagnostics and parts I didn't need, and don't want to spend anymore on that. the Honds dealership thinks that it could be plugged EGR ports on the intake manifold for the acceleration portion of the problem, and possibly the IAC for the drop in rpm's. at idle. Could anybody out there enlighten me? Does anybody have a possible procedure for checking the IAC Any input would be appreciated?

Thank you,

03-26-2004, 01:51 AM
Yea I had a problem like that before. I had a plug EGR line and also did you check your PCV valve on top of your heads? it might have a crack in it. But I know when my EGR line was plugs my car idle was really low. Run a presure test on your EGR valve line see if that is plug. Good luck on finding the problem.

03-27-2004, 09:39 PM
I had to replace my EGR valve not long ago. But I got cel w/ a code for EGR system malfunction. But, my car did have the same idle problem as yours. I replaced it........and it was fine for a while but now it still has a fluctuating idle. Don't replace the EGR valve without testing it first, it costs $300. Good luck.

03-29-2004, 07:42 AM
I know my solution may sound simple. But anyone that has had this problem will verify what I am saying is true. We have 11-14 year old cars. with 11-14 year old vacuum lines. They can be brittle and crack. A leaking vacuum line will send the various sensors bad signals and the engine can lope while idiling or idle erratically and it cvan also make the engine miss thoughout the driving speed range. I know it sounds simple, but ask anyone thats had a leaking vacuum line before what happens. They will cause problems and headaches. They are worth checking/replacing.

03-29-2004, 07:51 AM
To check your IAC unplug the electrical connector Turn your key to the on position but not running, unplug the electrical connector to the IAC valve. Using an Ohmmeter, test the resistange of the IAC vavle itself. It should be between 8 and 15 ohms. Then check each terminal on the AIC valve and the ground so see if there is continuity between each terminal. There should be no continuity. If there is, replace the valve.