Fluctuating idle, but stops if I tap the gas pedal.. - HondaCivicForum.com

Thread Tools Search this Thread
Old 05-16-2006, 02:50 PM
Thread Starter
Join Date: Feb 2006
Posts: 1
Default Fluctuating idle, but stops if I tap the gas pedal..

Hi everyone, I have been lurking for a while here and this is a great forum!

Okay, so I have a '95 EX Coupe, 1.6l, 5spd., and I have the dreaded fluctuating idle problem. I have, one at a time, disconnected the O2 sensor on the exhaust manifold, brake booster (plugged the port), fuel pressure regulator (plugged the port), and idle air control valve, but still get the fluctuation. It fluctuates from ~1,000 to ~1,250rpm, up and down over the course of a few seconds for each interval. I have no vacuum leaks as far as I can tell. I changed the PCV valve and this helped greatly (it used to rev from ~1,100 to ~1,500rpm before this), but did not cure the problem. Incidentally, when driving at a high steady speed (like driving on the freeway) with the engine cold ONLY, the CEL light comes on and gives a 'fuel pressure' code. I don't know if this is a related problem or not. Here is the weird part: if the idle is fluctuating, sometimes I can tap the gas pedal, bringing the rpm up to 1500-2000rpm and a few seconds after coming back down the idle will return to a steady ~700rpm or so and not fluctuate anymore. I can drive the car for a few blocks and then the fluctuation will return. Tapping the gas pedal doesn't always stop the fluctuating idle. I'd say it works about 65% of the time. Would this be the throttle position sensor? I haven't had time to test it yet. Any ideas? Thanks for any help!
Reply With Quote
Old 05-19-2006, 02:01 AM
Join Date: May 2006
Posts: 80
Default RE: Fluctuating idle, but stops if I tap the gas pedal..

Don't rule out vacuum leaks yet, because they can be very pesky and tough to pinpoint. But if the idle does return to a normal steady speed occasionally, you may not have a vacuum leak. Usually low fuel pressure won't increase idle speed, but lower it and cause a rough idle. Before I make any assumptions, the best thing you can do is find the correct OBD scanner that can read operational data from the sensors and other engine components. Check everything, or have someone who has a trained eye try and spot something unusual. This may sound stupid, but try looking at the throttle plate while the engine is running and the idle is fluctuating to make sure it actually closes completely. Maybe there is something binding in the accelerator pedal linkage or cable that won't allow it to close all the may and that's why tapping the pedal works sometimes. Open and close the throttle by hand with the engine both off and on...maybe you'll find something.
Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
Low idle before timing belt, fluctuating, irratic idle after JBaris Mechanical Problems & Technical Chat 6 11-22-2010 03:56 PM
Fluctuating idle? kroopz Mechanical Problems & Technical Chat 11 03-26-2010 10:35 AM
Fluctuating Idle? Jeremy102579 Mechanical Problems & Technical Chat 1 03-17-2010 07:18 AM
93 Civic EX fluctuating idle MR2nCivic Mechanical Problems & Technical Chat 8 03-01-2007 10:31 AM
horn stops working, works, then stops again vbcamry General Civic Talk 4 12-25-2006 02:19 AM

1995, car, civic, fluctuate, fluctuation, gas, h22, honda, idle, idles, low, pedal, pressure, stops, tap

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Featured Sponsors

All times are GMT -8. The time now is 09:09 PM.