1990 K5 5.7 TBI...stock engine

K, before I fixed all the electrical demons in my truck, the last time I took it on a lengthy drive, a total of 30 minutes...the SES light came on. Before, I had no gauges so did not know how pressure and temp were. Tonight, I took it for its first 30 minute 50 plus MPH drive since the last time the SES light came on, approximately one month ago.

Truck drove great the entire time. With gauges working now, Oil Pressure stayed steady at 40-45 the entire time, the tempterature stayed at 175 the entire time. No hiccups at all from engine noise and power. But, like clockwork, and kinda funny, in the same damn spot as before...the SES light comes on. Let the truck sit for 30 minutes when I got home and turn it back on and light was off.

My question is which scan device will read the computer codes? Is that scanner expensive? I know its wayyy preliminary, but truck smokes a little bit of oil, actually a lot at times, and I am wondering if O2 sensor is kickin a code out, as it probably should from all of the pretty blue/white smoke comin from the exhaust hahaha...actually, it has only been smokin on startup lately, but I know I have some internal engine issues with leaky gaskets and rings and whatever else is in there

 

your in luck... those trucks don't require a scan tool... you just make sure the key is off, and climb under the steering wheel, and find your ALDL or OBD.. and you get a jumper/piece of wire or something, and you install it between the top 2 right plugs.. then you turn the key to the on position.. NOT cranking! and start counting your lights.. and 12 will be normal. its due to the vehicle not running. but unless you cleared the codes by unhooking the battery for a couple minutes or pulled the ecm fuses, any codes should still be on there. and then its a matter of reading them .
it will flash, then space then flash twice for the 12 code.. and anything else beyond that you need to keep track of.


as for the ses light, its more then likely a o2... but with your handy jumper/paper clip it will help diagnose the problem for you.


hope this helps


Ck1500

 

Thanks! So, even though the check engine light turned off as soon as the truck cooled down, the code should still be there? thanks for the help!

 

yup unless you cleared it from the ECM... it should still hold the existing codes


once you get the codes, post em up here.. we will do our best to help ya out!!

hope this helps

Ck1500