Check engine light help

[DanielsHardLoyale]

Hi all! Just recently purchased a 1993 Subaru Loyale Wagon from a single owner. The beautiful green box is a 5 speed manual (which is very new to me). I have only had 3 hours of seat time, but have already fallen in love with the car.

There is currently a check engine light on and I cannot figure out how to the check codes! I have done a moderate amount of searching to find out that the diagnostic connectors are green and on the drivers side in the engine bay. When I plug those green connectors together the check engine light goes away and does not flash. I was under the impression the light would start flashing at me.

I have only done moderate car work on 2005 saturn ions. So I am new to most mechanical endeavors, but cant wait to put some blood, sweat and tears into this ea82. Im sure this is some simple issue, but my mind is all over the place. This OBD1 business makes my head hurt

Also I was wondering if anyone could tell me some average idle RPMs for the 1993 loyale manual transmission. It was stable around 1k the first week I drove it but sometimes sticks closer to 500.

Thanks!! Sorry if this is readily available information.

[wysubey]

Congrats on finding a 1 owner Loyale! Thats totally sweet. Mine is all rusty but I still love it and it runs great.

To read CEL codes, yes you plug in the green connectors. Then you have to take off the panel directly under the steering wheel to get a visual on the ECM. There's a little hole on the top that you can see a red LED which flashes your code. Kinda a pain in the butt to get your head in there to read it. Here's a paste of Loyale CEL codes. Not sure where I found this but it has proven accurate for my rig.

88 and later models with Single-Point Fuel Injection
11	Crank angle sensor or circuit
12	Starter switch or circuit
13	Crank angle sensor or circuit
14	Fuel injector – abnormal output
21	Coolant temperature or circuit
23	Air flow meter or circuit
24	Air control valve or circuit
31	Throttle sensor or circuit
32	Oxygen sensor or circuit
33	Vehicle Speed Sensor or circuit
34	EGR solenoid or circuit
35	Purge control solenoid or circuit
42	Idle switch or circuit
45	Kick-down control relay or circuit
51	Neutral switch continuously in the on position
55	EGR temperature sensor or circuit
61	Parking switch or circuit

 

So far, I've had codes 34, 32, and 21. All fixed now without too much trouble or cost, except wrenching the extremely stuck O2 sensor out. 

As for RPMs, those can change quite a bit depending on the engine temp. If its below freezing and I drive right away without any warm up, the first couple stop signs it will idle as high as 2k. Once it's warmed up, the spec is 700rpm for idle with the test mode connectors and no accessories. 

[wysubey]

Oh! Long flashes are the first digit, short flashes are the second. 

[DaveT]

When a code is currently upsetting the ECU, you don't have to mess with the connectors.  Just read the code/s.

If the idle is all over the place, the CTS may be failing.   It won't cause the CEL to light until it is really bad, but the car will run crummy long before that.  The CTS is a 2 wire sensor on the intake manifold near the thermostat. 

Plan on getting familiar with doing your own repairs, and keep an eye out for parts cars, spare parts, etc. As more go NLA every day.

[wysubey]

+1 for DaveT and CTS issues. One of the first things Dave helped me with.   Didn't realize the codes blink without test mode. 

[DanielsHardLoyale]

Thanks wysubey and DaveT for the help.

Found the flashing red light. It was only flashing quickly 6 times. I disconnected the green "test mode" clips and connected the white "read clips". Seems to be correct. It then displayed 3 long flashes and 4 short. Code 34? EGR? Time to do some more reading

[wysubey]

Yes, sounds like EGR. On mine, I determined that the solenoid was clogged and burned out and replaced it with OEM style. Check the impedance on it and see if it clicks nicely when you connect to 12v. 

[DaveT]

The ECU only knows if the solenoid is open circuit for code 34.  

[robm2]

The unstable idle can be a sticky IAC (Idle Air Control).  This is the ECU controlled valve that bypasses air past the throttle to control the idle speed.  It is the cylinder in front of the throttle body.  If you can get some carb cleaner in there, through the air inlet hose,  it might help.

[rickyhils]

DanielsHardLoyale   Maybe I have a fix for your problem if it is the same problem I had with my 1991 Loyale. If cel comes on and shows code 34 then it might be a bad IC chip inside the ECM module. I replaced that chip in my car and cel went away. Been two years now with no cel. There is a reference voltage that the egr solenoid needs from the ECM in order to give the AOK to the ECM. I checked reference voltage at egr solenoid and it was way below normal, showing 6 or 7 volts when  it should have read 11 volts. The first IC in the ECM is where the egr solenoid will trace to. Remove ECM box and open it up. It is a 10 pin IC that handles routing. It was 5 ICs for 10 buck [China] . Chip is dead easy to desolder and swap out as it is NOT SMD.  If you get intermittent cel w code 34 , don't waste 40 bucks on another eger solenoid. Contact me and I'll send you one of my extra chips for cost of mailing.