[nuodyowner]

I wonder if anyone can tell me what Helm says is the correct procedure to reset the PCM/ECU, I believe this is also called the learned idle procedure.

I am finding two different set of instructions on the internet.

After disconnecting the ECU fuse and waiting 5 minutes;

one sets says to start the engine without touching the gas pedal and let idle for 5-10 minutes - this presumes a pre-warmed engine, then take a above 40mph trip for about 30 minutes.

Another says to start the engine and maintain idle at 3K until normal temp (2 radiator cycles). Then let idle for 5 or more minutes.

I don't believe my Ody was properly set by the dealer, owing to poor mileage (a overy rich mix) and I want to try a correct fresh start.

 

[Guest]

http://www.odyclub.com/forums/showthread.php?s=&threadid=8272

 

[SportVan]

The dealers don't do anything about that when they get the vehicles. It is a procedure that doesn't require anything special to accomplish. You just drive your van normally and the ECU "learns" the necessary data. However if you have to have your van tested for emissions and it's really new you might have to simulate certain conditions of driving. The procedure is in the owner manual.

My experience is that the first 3000 km (+/-1800 mi) gave me a poor fuel economy then I noticed a remarkable improvement.

Your problem might not be related to the ECU but might be just breaking in period.

 

[BreakStuff]

Yes everyone..

The ECU will adapt to your particular driving habits..

but first..

THE ECU HAS TO LEARN PROPER IDLE SPECS INITIALLY TO ADAPT TO ANY PARTICULAR DRIVING CONDITIONS!!!!

Idle Learn Procedure: When Idle Learn Procedure: When and How to Do It

All Honda models with programmed fuel injection
(PGM-FI) have the ability to learn and adjust the
engine idle speed to optimize engine idle
characteristics.

The idle learn procedure should be done
whenever you do any of these actions:

• Reset, replace, unplug, or reprogram the ECM/
PCM

• Disconnect or replace the battery

• Do engine work that requires R&R of the
intake manifold or the throttle body
To allow the ECM/PCM adaptive idle speed
system to learn and adjust the engine idle speed,
here’s what you do:

• Make sure all electrical items (A/C, audio unit,
defogger, lights, etc.) are turned off, then start
the engine.

• Let the engine reach its normal operating
temperature (the cooling fans cycle twice; the
coolant temperature is about 194° F).

• Let the engine idle for at least 5 minutes with
the throttle fully closed and with all electrical
items turned off.

• If the cooling fans cycle on while doing an
adaptive idle learn, add the time the cooling
fans are on to the 5 minute adaptive idle learn
time.

 

[nuodyowner]

I have no doubt that the dealers will tend to skip this step. The owner's manual details a process which is time consuming - a 20 minute drive after more than 10 minutes of warmup.

However, Honda's own PDI (Pre Delivery Instructions) for dealers lists the following

"Perform the Idle Learn Procedure"
The idle learn procedure must be done at PDI after the
fuses are installed so that the PCM can learn the
engine idle speed characteristics. If it is not done or
done incorrectly, the engine may have an erratic idle.

This procedure also must be done whenever you do
any of the following:
• Disconnect the battery.
• Disconnect the PCM.
• Reset or replace the PCM.
• Remove the driver’s or passenger’s under-dash
fuse/relay box.
• Remove the BATTERY (120A) fuse from the underhood
fuse/relay box.
• Remove the BACK-UP, ACC (40A) fuse from the
under-hood fuse/relay box.
• Remove the No. 13 CLOCK, BACK-UP (15A) fuse
from the passenger’s under-dash fuse/relay box.
• Remove the PGM-FI main relay.
• Disconnect the starter cable terminal from the underhood
fuse/relay box.

Then it quotes a truncated procedure which seems no more than an engine warmup.

It sounds like they are providing a less than ideal prep option for the dealers because they won't do it otherwise.

I am experiencing a slightly erractic idle - like a regular stumble - and low gas mileage and still within the first 1k miles.

I presuming a reset of the PCM could not hurt and maybe help, so I'm going to give it a try after finishing this tank to get a base line on gas mileage.

Anyone know of a reason why I should stay away from this?