Check Engine Light On - ????

How to fix gremlins & general maintenance issues ...
Post Reply
User avatar
Subarooted
Junior Member
Posts: 21
Joined: Thu Nov 03, 2005 10:00 am

Check Engine Light On - ????

Post by Subarooted » Sun Feb 05, 2006 4:38 pm

Well I have just come back from a month of holidays in which I travelled 6000km up and back the east coast. About half way up I had some engine trouble - lost all power on the highway, then it wouldn't start for a while, clean the plugs, checked for spark and then it worked again ... ! bought some new ignition leads and all seemed fine.

A few hundred kms later the "check engine" light came on and remained on for the rest of the trip...! Engine doesn't seem to be running badly, no noticable loss of power - but every now and then it will die when Idling... Service book says that 'check engine' means contact your authorised subaru dealer immediately.. Given that this is highly unlikely to happen - can you guys shed any light on the mysterious light. Think it may have something to do with the EFI sensors or something??

BTW - the vehicle is an L-series, MPFI stock EA82, sedan.

Cheers for your help, might end up just sticking some electrical tape over the light....

User avatar
LTurbo
Junior Member
Posts: 330
Joined: Tue Oct 04, 2005 10:00 am
Location: Canberra

Post by LTurbo » Sun Feb 05, 2006 6:29 pm

When the ECU receives error's from its sensors, it flashes the check engine light. You can see what these codes are by counting the flashes from a small red light on the ECU (for example 12 flashes is code 12, which is a fault with the starter switch). The procedures for checking the codes and what the codes mean are slightly different between carbureted and fuel injected models. If you have a Haynes or Gregory’s manual it should tell you what the codes are and how to check them.

If you do not have a manual I can read mine and tell you how to check the code.

User avatar
stamp_licker
General Member
Posts: 1066
Joined: Wed Oct 05, 2005 10:00 am
Location: Kallangur.Bris North

Post by stamp_licker » Sun Feb 05, 2006 8:11 pm

yep my wag does it all the time i just lift my foot of the throttle and the light goes off.this mostly happens on the highway but can show up at 60km/hr.also did it more often when the pod filter was dirty,changed it back to standard.subaru shop said something about dodgy o2 readings changed the sensor it still does it.lots of posts about it on the usmb, most of those guys use the tape trick.doesn't seem to do any damage i've lived with it for 2yrs and it's still going.have you tried clearing the codes ?
[SIGPIC][/SIGPIC]aka the_postie
Building a hardcore postie:D

User avatar
Subarooted
Junior Member
Posts: 21
Joined: Thu Nov 03, 2005 10:00 am

Post by Subarooted » Sun Feb 05, 2006 9:49 pm

first of all, thanks for you responses.

Well I do have a gregs manual but can't find anything about the ecu in it, the electrical section is fairly basic and the book doesn't cover EFI or Turbo models anyway.

Now - When you turn the car on, the warning light takes about 5 minutes to come on. During this time there is a green LED on the ecu which flashes exactly 7 times. Once the warning light is on this changes however, and now the LED on the ECU flashes five long flashes then one short flash, six in total.... Go figure!!

If you can make any sense of this then it would be a great help

Cheers

User avatar
mattl200
Junior Member
Posts: 324
Joined: Sat Oct 08, 2005 10:00 am
Location: NW Tasmania

Post by mattl200 » Mon Feb 06, 2006 8:32 pm

http://www.westol.com/neper/ecucodes.html
ecu codes

51 Neutral Switch (Manual Transmission Models)
51 Inhibitor Switch (Automatic Transmission Models)

User avatar
Subarooted
Junior Member
Posts: 21
Joined: Thu Nov 03, 2005 10:00 am

Post by Subarooted » Mon Feb 06, 2006 10:35 pm

great, thanks for that,

next question...

what is a neutral switch and how do I find and fix it..?

I can't find anything in my gregs manual about it, and can't find it on the wiring diagram either....

User avatar
Subarooted
Junior Member
Posts: 21
Joined: Thu Nov 03, 2005 10:00 am

Post by Subarooted » Sat Feb 11, 2006 3:26 am

well now my car had shat itself....

I was driving home from work tonight and the engine just shuiddered and stopped... would not have a bar of it!!. And in possibly the worst place that melbourne has to offer - for all you melbourne lads out there - I was in peak hour traffic, city bound, on the south eastern freeway - bumper to bumper mind you - I took the toorak rd exit - its a big hill, had to push it all the way up the off ramp, the fuckers were tooting and carrying on the whole way...

Anyway, don't really get why it wont start... That engine light is dogging me, but I reckon that might not be the problem, anyway - better to rule things out first

CAN SOME PLEASE TELL ME WHAT THE FUCK A NEUTRAL SWITCH DOES AND WHERE IT IS? WOULD ITS FAILURE CAUSE MY CAR TO CONK OUT?? IF YOU DONT KNOW THEN AT LEAST SAY SO, THE SILENCE IS KILLING ME.

User avatar
BaronVonChickenPants
General Member
Posts: 1187
Joined: Tue Oct 04, 2005 10:00 am
Location: Nowra, NSW

Post by BaronVonChickenPants » Sat Feb 11, 2006 8:42 am

The neutral switch just tells the ECU if the car is in nuetral or not, in an auto it is the switch that stops the car starting unless its in P or N, but I don't think it should stop the car starting in a manual, just guessing though.

Jordan.
To become old and wise, first you must survive being young and dumb.
Image

User avatar
tim_81coupe
General Member
Posts: 1693
Joined: Tue Oct 04, 2005 10:00 am
Location: Perth

Post by tim_81coupe » Sat Feb 11, 2006 1:45 pm

In a manual the neutral switch won't stop the car starting. Upon selecting a gear the revs raise by about 100-200rpm to make takeoffs easier. That's all it does.

I've never hooked up the neutral switch in my coupe, never needed to. Sounds like the problem your car's got is quite more significant.
82 MY Wagon, EJ20G

87 RX, EJ20G

89 Brumby, EA81

12 BRZ, FA20

User avatar
Fury
Junior Member
Posts: 242
Joined: Wed Oct 05, 2005 10:00 am
Location: Central Coast / Hunter (NSW)

Post by Fury » Sat Feb 11, 2006 2:23 pm

I, along with many others, have found that the code lights, are often only a guide to what is really wrong. It shows a symptom, not the cause.
If you can remember anything that may be happening anytime that this light goes on - revs, gear it's in ( even something stupid like going round a corner). It could be as simple as a wire shorting to the body or connector that needs cleaning.

I hade 4 ecu code lights, which related to air flow issues - only to find that there was a air bypass hose that had come adrift - altering the readings of the airflow sensors to the ECU. Each of the codes related to parts that checked out fine.

Have a good look at connectors, joins to sensors and reset the ecu. (take the posative battery terminal off for at least 1 minute ( please someone correct me if i'm wrong) this should reset the ecu back to standard default.

Intermittent problems are a curse. :?

If is works fine , then suddenly goes bad, then comes good again without much effort, it sounds to me like something simple which can change easily - like an electrical connection.

Good luck - heres knowing Murphy ( Murphy's Law strikes again)
Chris :cool:

'88 Vortex AWD turbo with "go hard" attitude -

WRX EJ20G and box , TD05 Turbo and 4.111 running gear.
5 Stud conversion (Crossbred Performance) Multi pot GT Legacy brakes and 17" rims
Plenty of plans... the plans are getting done slowly;).... getting there - NOT! ;)

User avatar
Subarooted
Junior Member
Posts: 21
Joined: Thu Nov 03, 2005 10:00 am

Post by Subarooted » Sun Feb 12, 2006 7:36 pm

well, sorry about all the agression in my previous post... I was actually pissed as a fart when I wrote that on friday night, after having the car break down on me on the way home from work.. Sorry for the bad language.

thanks for all your responses - I really appreciate it

Update.

Well I did some diagnostic checks on sat morning, this is what I found...

- Couldn't get spark out of any of the leads.
- Distributor points fairly worn, I will replace the cap
- Charge on both of the low tension leads going into the coil - this suggests to me the coil is working - also I would expect that if the coil was to fail it would fail suddenly - and the car has been running intermittently
- No spark when I connect a plug to the coil high tension lead - this would suggest that the coil is buggered but I was told that with electric ignition (my electronic ignorance is about to become blaringly obvious) you could not expect spark from the coil lead - and that the module may be stuffed??

One of the most annoying things about all this is that my gregs manual does not cover EFI engines nor does it describe the distributor that I seem to have. Anyway, went to repco to get a new dizzy cap and module but they can't seem to work out whcih distributor I have either - I guess it might be one that was put in aftermarket...

Also, why would a manual vehicle have a neutral switch? I have changed my gearbox and rewired it and I have never wired in a neutral switch - isn't that just an automatic transmission thing.

Going to the automotive electrician tomorrow with my dizzy - Ill keep you all posted.

User avatar
Gremlins
Junior Member
Posts: 121
Joined: Thu Oct 06, 2005 10:00 am
Location: South Australia

Post by Gremlins » Mon Feb 13, 2006 1:16 pm

No spark could be a number of things. The coil in my car died a while back exactly the same symptoms as you describe, just a shudder and then nothing. I thought it was the ignition module as a few rough checks using a multimeter on the coil looked OK, but turns out it must have had some sort of insulation breakdown on the high voltage side. Could also be the LHS (Longer) CAM belt broken. Other than that we'd probably need to know if you have the optic EA82T (no vacuum advance on dizzy), or the older more common EA82T found in australia which does have a vacuum advance unit on the distributor.

User avatar
AndrewT
Senior Member
Posts: 4777
Joined: Tue Oct 04, 2005 10:00 am
Location: WA
Contact:

Post by AndrewT » Mon Mar 13, 2006 1:24 am

Mabey check the ballast resistor.

User avatar
fredsub
Junior Member
Posts: 947
Joined: Fri Oct 14, 2005 10:00 am
Location: the gong

Post by fredsub » Mon Mar 13, 2006 10:06 am

AndrewT wrote:Mabey check the ballast resistor.
don't think so! should be no ballast resistor for a electronic dizy.
Only mechanical points need those things.

I would 2nd replacing of the cap, in meantime could try scratching crust off the terminals and try it, might work for a bit. I had similiar experience/symptom, replacing cap fixed it.
By the looks of it, a standard cap (ie off the carbi hitachi unit) seems to fit the turbo dizy (one with the vacuum unit in it)...I don't know whether it workis in practice tho....? anyone know? do you need to get the oem part from Subaru?

Post Reply

Return to “Electrical, Wiring and Lighting”