i just bought a GM Code Reader. when i follow the instructions i get code 12 which means in the book "Diagnostic mode; no distributor signal to Electronic Control Module; System PASS" I think it means something good due to the system PASS message at the end, please help me with this. My car is a 1993 SL1Edited by: MCapone

Indeed -- code 12 (with no others) means all is well

Why would you do that? This is all you need:

https://jawproducts.authsecure.com/i...erclip1_25.jpg
Heres instructions on how to retrieve codes:
http://www.differentracing.com/tech_...diag_info.html

Diagnostic Trouble code chart:
http://www.differentracing.com/tech_...dtc_chart.html

Transaxle trouble code chart:
http://www.differentracing.com/tech_...ttc_chart.html

I donno, just to make my life easier, all the pins are in the right spot, and i mean it was only 19.99$ so i decided to get one. My service engine light kept on coming on so i wanted to see what the trouble was with ease. can anyone tell me why it kept on coming on and then when i found out what the code was, it said system pass. It really confuses me. I also have a rad leak (atleast i think it's my rad) and i bought a bottle of that barz leaks and put that into er' but she still leaks on me, i notice er' in the mornin when i go to go to work. but it doesn't leak in the parkin lot at work, only on my slab at home. the whole bottom of the block is soaked with coolant towards the back, but i park on an upwards sloped angle and it seems to be coming from the front driver's side and running down the slab. I can't find the leak anywhere and i dont wanna take it to a garage for them to find it and them cost me a pretty penny in labour to find it and fix it. I put new clamps on the rad hoses, and if there was a hole in the hose the bars leaks would fix it, wouldn't it? thanks for your help

I think for $20, having the codes made clear is worth the price. I prefer a staple gun staple to a paperclip, but the Haynes manual list of codes is for a later model than my 94. The correct trouble codes are hidden in the test but you need to know the problem before you can find the corresponding code.


I have no idea why some codes stick and others just make the "check Engine" light blink, but it certainly is the case.


As for rad leak stop, I like to think of it as a piece of bubble gum or a bandaid. It is only a temporary fix, not a solution. You haven't fixed your problem, only bought some time (maybe). You really need to find where the leak is and fix it. You also need to flush the cooling system to get the remaining leak stop goo out before it clogs your rad passages.Edited by: CALegalVette

thanks alot man, i found where is was coming from, now it's leaking like crazy, at the bottom drivers side cuplet on the rad. it's drop after drop now. and if i were to temp. fix it, how would i put the gum in it? chew it and put it in the coolant jug? there is no cap to my rad, so i wouldn't be able to put it there.