PGM-FI Waring Light - 1987 Honda Accord LX

Issue with PGM-FI warning light started after SMOG Repairs.

1987 Honda Accord LX with 124k miles

PGM-FI light comes on consistently after 15 - 30 minutes of driving.
Usually preceded by some engine stuttering then as soon as the light
comes on the car drives smoothly. Of course the light resets as soon
as I turn off the engine.

The smog repairs included replacement of the O2 sensor and
re-adjustment of the timing back to specs.

I checked the LED on the control unit under the driver's seat. There
is a single LED which is blinking once.

The smog repair shop is stating that they are unable to reproduce the
issue and that it is unrelated to the repairs they made. The car was
running fine just not passing smog before the smog repairs (never had
the PGM-FI light up while driving before). The PGM-FI light came on as
I drove the car home from the SMOG Repair Shop after spending $378
bucks. Now they've had the car for several days with no results and
have tried to chg me another $75 for diagnostics which I've refused to
pay. I'm now driving the car for the past 2 weeks with the light
coming on consistently after 15-30 min usually on the freeway and
usually preceded by some engine stutter or sluggish acceleration... as
soon as the light comes on the car runs fine for the rest of my 1 hour
commute.

If any one knows what the LED codes are, specifically what blinking
once indicates please let me know.

Thanks in advance,
Brian Johnson

 

here is something that can help you

http://www3.sympatico.ca/ecutuning/tech/ecucodes.html

--
Eric Fournelle
Alarme-O-Tech
514-730-5169
www.alarmeotech.com

 

The switch over smooth running after stuttering is the system going "open
loop", instead of basing engine parameters on exhaust measurement by the O2
sensor. Its basically a "limp" mode and while it feels OK, since the O2
sensor is no longer being used to control combustion settings, it *can*
damage your catalytic converter with clinker if left long enough.

O2 sensor is the main suspect here I'd think. There are what's known as
"Universal" type sensors which rarely work right for long - some of those
don't even have a connector on the wire(s). Ask the shop which brand and
type they used. Experience here has been that what works best for Hondas
is the Honda part which may also be available in aftermarket as an OE type
but only if it's an exact match, e.g. the identical part made by Denso or
NTK.

Rgds, George Macdonald

"Just because they're paranoid doesn't mean you're not psychotic" - Who, me??

 

This probably indicates a ridiculously lean mixture before it entered a
limp mode (which is noticeable by a powerful smooth drive after.)

Car probably ran rich and failed smog before. Now it likely runs
too lean. Normal O2 should react quickly to changes. Did you
install one or both? I've installed many BOSH O2 sensors on these
Hondas and has worked fine. But not all brands should work.

Practice caution. Limp mode means limp home. 1 hour
commute may further damage O2 sensor or catalytic.

More likely a Faulty Primary Oxygen Sensor.

Technical stuff: O2 sensor behaves in three voltages. 0.1, 0.4
and 0.9-volts. Connect analog or DMM to the sensor and
gradually accelerate. Good sensors try to stay at 0.4-volts
and jumps to 0.1-volt quickly when gas is released. In your
case it's probably stuck at 0.9-volts.