Can you even pull codes on a pre-OBDII car?
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Can you even pull codes on a pre-OBDII car?
^ I didn't think so, that's why I haven't tried to pull codes. But that's another thing to research / try.
And no, never threw a CEL, that I saw anyway.
Yes, you can.
http://www.miata.net/garage/faultcodes.html
So does OBDI store codes without the CEL being on, like OBDII?
I was going to do the jumper trick anyway just for good measure when I got back to it, but didn't think it stored codes without the CEL being on.
It stores the codes.
Eliminate the fuel system variable first as it's easier to track down. I'm starting to think it could be the CAS or a coil pack too. Remember, the CAS drives the coils (4 pins on the coil) which drives the tach and computer.
I had no pertinant codes.... and the car ran fine between crapping out. Was more likely to do it when warm...
Finally got a chance to mess with the car. Bought a spare CAS from a 90, read they will work in a 94, so i'll be swapping it today if I can make the car crap out.
Showing from what I can tell,
codes:
01 IGF signal
04 SGC signal
08 Mass Airflow sensor
09 Engine coolant temperature sensor
And if my thinking is correct that the long flashes mean 10...
10 Intake air temperature sensor (mass airflow sensor)
16 EGR function sensor
The MAF and possibly the IGF could be explained by me adding a custom intake and forgetting to plug the MAF back in, also testing the MAF connection when the car was acting up. Keep in mind I had issues with water in the plug wells recently, and throwing the timing gear, so that may have caused some codes. I didn't know to clear the codes.
The other codes...not sure. I read a bad CAS will throw a 3 or 4, so that might be an indicator.
For now it's idling mercilessly while I do a brakejob on the minivan, until something interesting happens.
Update: The car purred like a kitten for an an hour 45 mins, half that with the AC on. Then died a few times. Cranked and revved the engine a little bit then it died for good, wouldn't start. 30 mins later it fires right up and runs no problem.
I'm convinced now it's the CAS, so i'm swapping it out now...well when the engine's not so bloody hot.
I removed the battery but the codes were still there. I was desperate to finish the brake job and it looked like rain so I left it that way. I know fail. I guess its worth it to try again when I get back home.
IIRC, you need to tap the brake petal a few times with the battery disconnected to clear the codes.
^That worked.
Small update, I cleared the codes and ran it again till it died, again almost an exact 1 hour 45 min. It's throwing only a code 1 :IGF signal.
Still think it's the CAS. Homework is calling so I won't be swapping it till next weekend. In the meantime i'll read up on IGF signal errors.
Well, wasnt the cas... car broke down in the heart of ghetto ass irving.
Swapped it friday. couldnt make the car die so thought it was good enough to drive. Drove fine for the last couple days until now. Waiting till it cools off hopefully I can make it home and swap cars in time to make class...wishfull thinking, haha.
So wher,to go now?? Coil pack?
What code is it kicking now??
Just code 1.
Let it cool down for about an hour, and it ran like a top all the way home.
Edit: Anyone know how similar 99 coils are to a 94? I found this test diagram.
http://www.miata.net/garage/coilpack_test.jpg
Not really interested in blindly replacing anymore parts, I thought about testing the coils next time I make the car die, but not getting much love from Miata.net searches on this.
Wait, thinking about this again... the car had spark before (in cyl 1 at least, need to test the rest later), so I'm thinking could be some relay or whatever that controls, or influences the injectors.
But wouldn't cut fuel cause sputtering before it dies?
Sorry, just thinking out loud, I don't have a clue in this area. :scratch::scratch::scratch::scratch::scratch::scra tch::scratch:
Oh, another thing, while swapping the CAS out last weekend, I did notice some animal had chewed the rubber on the O2 sensor wire. Didnt think it would be a problem since there wasn't any wire showing, but just now thinking it does run next to the header... I think it would run like crap if it was losing signals, but could the ECU cut ignition from this?
I have seen random chew marks here & there under the hood. None have been exposing bare wire or anything so I haven't wanted to go there for the impending nightmare that would ensue and since the cars ran fine for the last few years.
I'd check the coil. I had a Honda that did the same thing and it was the coil. I may even have a spare you can try.