Brief 'check engine' light blink
 

This has happened twice in the past week. I was driving along and my check engine light came on for about 1 second and the went off. Specifically, it was when I started driving, just got on the highway, and was in second or third gear. In other words, it was my first time through the gears on my way up to highway speeds.

The symptoms (minimall)
-gas mileage in the low 20s. This doesn't bother me, I live 5 miles from work and all my cars have low gas mileage unless we go for a long trim.

-rough idle. Again minimal. You cannot see it on the tach. I can feel it because I try to pay attention to these things. Passengers have never been able to notice

Changes I have made in the last 3 months
-change to all synthetic fluids (previous owner used petroleum based) Just changed the oil last week and thought I overfilled it a little. Let that out the next day.

-K&N replacement filter

-tranny filter and cooler installed

-power steering o ring fix

-rotated tires and painted center caps

One of these two may be the culprit

-resistor mod two weeks ago (replaced the resistor after one day)

-last week, swapped ECUs from another '92. This one had the EPROM mod, tan resistor cut, and black one crushed. Mine had none of these.

So, the check engine light makes me fear impending doom. I don't know where to start to look. The car runs great. Any advice would be greatly appreciated.

Oh, nvrmore, did anything funny happen in the brief time you had this ECU in?

Thanks

Re: Brief 'check engine' light blink
 

Nope, wouldn't have sold it if it did. :(

As for the light, could be a lot of things unfortunately. My guess would be a sensor that is starting to flake out. Mine is starting to do that as well however it will go on for a few minutes at a time. I'm guessing mine is an oxygen sensor.

So this is where the big question comes out. Who wants to post the how-to on how to check the engine codes again?? :) I need them again too. :)

Ryan

To retrieve codes:

1) Remove the kick panel just beside the left foot rest on the driver's side.
2) Locate blue wires.
3) Locate black connector. Hold it notch up.
4) With ignition off, insert one of the wires into top row, 2nd pin from left.
5) Turn key to on position, but do not start the car.
6) Watch blinky check engine light on dashboard. Count blinks. Long blinks = 10, Short blinks = 1.
7) Keep watching blinky light until you get mesmorized. :D

You may want to clear codes to make sure that old codes are removed from system before determining problem. I would personally read codes now, clear the codes, then wait until the CE light comes on again to retrieve the codes.

To clear codes:

1) With engine off, stick the blue wires to 1st and 2nd pin in the top row counting from left on the black connector, with notch facing up.
2) Start car. Shut off car. Remove pins.
3) Read codes to make sure they are clear. No codes = steady blinks at 1/4 second intervals.

Clear as mud? :D

Those that require pics, I can take them when I get back into Toronto on Monday.

VK
I miss my SVX.

We have a winner! Now for the grand prize, provide a listing of the codes themselves and how they equate to blinking lights.... :D

Ryan

Re: Brief 'check engine' light blink
 

Why was the resistor on the ECU cut?

As for 'feeling' a rough idle, I used to swear my SVX did the same thing. I started buying gas from a different station - I suspect that the discount station I was going to was mixing octane ratings. You are putting in premium fuel, right?

My guess is going to be that you need to replace one or both of your exhaust O2 sensors. 90% of the time that I've had a 'check engine' light come on in any of my cars was due to a faulty O2 sensor. That could also cause your poor mileage or rought idle.

Re: Re: Brief 'check engine' light blink
 

The tan was cut from the dealer. When they install the new prom chip they cut it.

Re: Re: Brief 'check engine' light blink
 

The TSB states that if you do the "noise supressor" "bead crush" AND your car has the eprom upgrade, you must cut the tan resistor.

Re: Re: Brief 'check engine' light blink
 

Sorry, I didn't mean to imply that you would have sold me something that malfunctioned. Just looking at the problem from different angles and the possiblilty that something came up that you found a fix for. From looking at your site, you're a pretty ingenious fella.:D

Re: Re: Brief 'check engine' light blink
 

I get my gas from one of 2 stations. Neither are discount or mini marts. I use either Sonoco Ulara 94 or Amoco 93.
Will the O2 sensor show up as one of the ECU codes?

Thanks, I'll try the procedure. Actually, I thought the instructions were fine. I'll probably wait to find what the codes mean first though. Admittly, I havent searched the archives for them yet.

What, you're going to make me do ALL the work, even while I'm on vacation?? ;)

-- 1988 and Later Models with Multi-Point Fuel Injection --

CODE PROBABLE CAUSE
11 Crank Angle Sensor or Circuit
12 Starter Switch or Circuit
13 Cam Position Sensor or Circuit (TDC Sensor on Justy)
14 Fuel Injector No. 1 (Legacy, Impreza, Justy, SVX)
14 Fuel Injector No. 1 and 2 (XT, Loyale, GL, DL)
15 Fuel Injector No. 2 (Legacy, Impreza, Justy, SVX)
15 Fuel Injector No. 3 and 4 (Loyale, GL, DL)
15 Fuel Injector No. 5 and 6 (XT-6)
16 Fuel Injector No. 3 (Legacy, Impreza, Justy, SVX)
16 Fuel Injector No. 3 and 4 (XT)
17 Fuel Injector No. 4 (Legacy, Impreza, SVX)
17 Fuel injector No. 1 and 2 (XT-6)
18 Fuel Injector No. 5 (SVX)
19 Fuel Injector No. 6 (SVX)
21 Coolant Temperature Sensor or Circuit
22 Knock Sensor or Circuit (Right Side on SVX)
23 Air Flow Meter or Circuit (Exc. Justy)
23 Pressure Sensor (Justy)
24 Air Control Valve or Circuit (Exc. Justy)
24 Idle Speed Control Solenoid Valve (Justy)
25 Fuel injector No. 3 and 4 (XT-6)
26 Air Temperature Sensor (Justy)
28 Knock Sensor No. 2 (SVX, Left Side)
29 Crank Angle Sensor (SVX, No. 2)
31 Throttle Position Sensor or Circuit
32 Oxygen Sensor or Circuit (No. 1, Right Side, On SVX)
33 Vehicle Speed Sensor (VSS) or Circuit
34 EGR Solenoid or Circuit
35 Purge Control Solenoid or Circuit
36 Air Suction Solenoid Valve (Impreza)
36 Ignitor Circuit (Justy)
37 Oxygen Sensor (No. 2, Left Side, On SVX)
38 Engine Torque Control (SVX)
41 Air/Fuel Adaptive Control
42 Idle Switch or Circuit
43 Throttle Switch (Justy)
44 Wastegate Duty Solenoid (Turbo Models)
45 Pressure Sensor Duty Solenoid (Turbo Models)
45 Atmospheric Pressure Sensor or Circuit (Non- Turbo Models)
49 Airflow Sensor
51 Neutral Switch (Manual Transmission Models)
51 Inhibitor Switch (Automatic Transmission Models)
52 Parking Brake Switch (Exc. Justy)
52 Clutch Switch (Justy)
55 EGR Temperature Sensor or Circuit
56 EGR System
61 Parking Brake Switch (Loyale)
61 Fuel Tank Pressure Control Solenoid (Impreza)
62 Fuel Temperature Sensor (Impreza)
62 Electric Load Signal (Justy)
63 Fuel Tank Pressure Sensor (Impreza)
63 Blower Fan Switch (Justy)
65 Vacuum Pressure Sensor

VK

how to
 

Randy, how about moving the codes & procedure to "how to"?, if it's ok with VK:)

Re: how to
 

Those aren't MY instructions. They're merely my regurgitation of other sources of information. :D

As for the codes, those I found from the alt.autos.subaru newsgroup.

Sure, why would I mind?

VK

Okay, I was gonna make you search and find them yourself, but, what the hell, I'm a nice guy. :D

Try this:

Re: how to
 

David,
I've scanned all three pages of the manual regarding the codes and will drop them into a folder in the How-to locker. Meanwhile, VK, you've been absent for a while. Good to see you back. :D