TylerW

Hey everyone:

I bought a 1996 Accord LX 5-spd a few months ago, and althought it is a great car, there are a couple problems occuring I need to fix:

First problem is that when warmed up, the engine idles too low. When I push the clutch in slowing to a stop, the idle drops to about 400 rpm, then a few seconds later, raises up to about 600. Today it has even started stalling completely. I cleaned the screen in the Idle Bypass Soleniod, but it didn't help at all. I feel it is working because the idle is higher when cold, and the idle also kicks up when the AC compressor engages...however, it seems too low all the way around. I don't think Honda's are supposed to idle this low.

So, what is the correct idle speed for this car, and is there a way to adjust the base idle on the throttle body?


The second problem is that the Check Engine light is on, and the ECM is setting two hard fault codes: 1 each for the front and rear 02 sensor heater circuits. I found a page a while back that detailed how to diagnose that problem, and it seemed to infer that the problem is either bad sensors or no voltage to the circuit because of a Main Relay defect. It seems this particular problem is common on the 94-97 cars..anyone else dealt with it? I don't know if it's related, but my car runs better when it's cold than it does hot. Hot, it seems to surge going up through the gears.

Thanks for any advice...

i20ar

my car (96 ex) idles around 500rpms .. so i think your car is normal unsless it stalls but yea when i drive my car around... it almost seems like its gunna stall but it never does... and when you turn on your a/c it is also normal for the rpms to raise a lil... if you wanted check all your vacum lines and maybe change your air filter...

as for you car running better when its cold.. it may feel that way to you.. but no car ever runs better when its cold

im not sure about the ecu.. problems but yea just letting you know your idle seems normal

The_Todd

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TylerW &raquo;</TD></TR><TR><TD CLASS="quote">
First problem is that when warmed up, the engine idles too low. When I push the clutch in slowing to a stop, the idle drops to about 400 rpm, then a few seconds later, raises up to about 600. Today it has even started stalling completely. I cleaned the screen in the Idle Bypass Soleniod, but it didn't help at all. I feel it is working because the idle is higher when cold, and the idle also kicks up when the AC compressor engages...however, it seems too low all the way around. I don't think Honda's are supposed to idle this low.

So, what is the correct idle speed for this car, and is there a way to adjust the base idle on the throttle body?

</TD></TR></TABLE>

Your idle sounds fine as stock idle is around 750 rpms...this will differ but you can adjust your idle by adjust the idle screw located on your intake manifold just above your throttle body. Here is a pic:



Look at the throttle body there is a circle just below the number 3. Turn your car on and adjust that screw until your idle bumps up slightly. The idle will adjust normally like you stated when the a/c comes on because of the load on the engine.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TylerW &raquo;</TD></TR><TR><TD CLASS="quote">
The second problem is that the Check Engine light is on, and the ECM is setting two hard fault codes: 1 each for the front and rear 02 sensor heater circuits. I found a page a while back that detailed how to diagnose that problem, and it seemed to infer that the problem is either bad sensors or no voltage to the circuit because of a Main Relay defect. It seems this particular problem is common on the 94-97 cars..anyone else dealt with it? I don't know if it's related, but my car runs better when it's cold than it does hot. Hot, it seems to surge going up through the gears.

Thanks for any advice...</TD></TR></TABLE>

Sounds like your o2 sensor is bad...I don't think both would be bad but I would try replacing the one nearest to the exhaust manifold as that one tends to go bad first (from my experience).

Hope that helps.

Chiovnidca

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TylerW &raquo;</TD></TR><TR><TD CLASS="quote">

The second problem is that the Check Engine light is on, and the ECM is setting two hard fault codes: 1 each for the front and rear 02 sensor heater circuits. </TD></TR></TABLE>
Have you checked your fuses? Is there 12v getting to the o2 heaters?

Duane_in_Japan

You should remove the throttle body and completely clean it and the hole below #3 and I think screw #1 is the adjuster??? Turn it CCW to let more air in and raise the idle, if not its all dirty inside. Your car should be at a higher idle cold partially due to the idle controler that you cleaned the screen, it is warmed up by coolant (antifreeze), it heats up a wax pellet I believe that expands closing off the air bypass hole lowering the idle as the car warms up.

I have seen pics like the one above and it did not show the screen as a part, it is available in Japan with the seal kit to reseal this thing.

On you car the idle for the AC , power steering and I think just dropping it in gear is all controlled by the ECM and the ISCV motor, is this right guys. The AC Computer (amp) and the PS pressure switch sends a signal to the ECM and it commands the ISCV to do its thing after the car is in Closed Loop operation, (warm). It is already idled up while cold in Open Loop operation.

I do not think that this is it as you didnt mention any maintenance but installing the wrong part number O2 sensors will throw this code, they are still three wire sensors but the three pins in the connector are configured (indexed) incorrectly. Look for a rubbed through wire harness around the tranny, exhaust or a bracket near the harness, chaffing is a major contributor to these O2 codes.

deserthonda

on the pic screw # 1 is the adjuster,, take it complitely out,ake sure the o-ring is ok , get some carb cleaner spray and spray it in the hole in throttle body also clean the screw ,,,,remove the tube going into throttle body. hold the butterfly open and clean out all around that area with carb cleaner and a rag u might have to wet the rag and scrub all the junk off..,,,,,,,,,,once all clean put screw back in and adjust idle to 750 once done put some honda bond or silicone on the back of the screw so it does not work its way out .................to raise idle as stated by Duane u go counterclock ,,,,,,,, give that a shot see if it helps

TylerW

Thanks guys for the great info..I will post back when I have some news to report. As far maintenance, I don't know. It looks like it has never had anything changed that I can tell. Thanks again.

SlowAccordEX

This same thing happened to my friend's subaru. It ended up being a combination of a bad o2 sensor and a coil pack. Hope that helps.