Check engine light [Archive] - TheDieselPage.com Forums

bigtallguy

09-26-2003, 14:42

I have a 1995 Chevy with the 6.5 in it and the check engine light comes on sometimes when I am going down the interstate, usually doing 70-75. It doesn't come on all the time and when it does it only stays on for a few seconds and then cuts off again. It only happens at those speeds. Anyone had this problem before or know how to fix it? Thanks.

pannhead

09-26-2003, 15:13

having a 95 all you need is a paperclip to check codes (check reference section)or JK website...if i were to guess i'd say a 36 or 78....get back to us on it

ucdavis

09-26-2003, 16:16

See:
http://www.thedieselpage.com/members/trblcode.htm
for process of code retrieval. Gives a list of the DTC (diagnostic trouble codes) names. Pull codes & post for best advice.
Welcome to the board!

bigtallguy

09-26-2003, 16:23

I did the thing with the paperclip and it flashed 3 codes. 32 (EGR circuit error), 33 (EGR control pressure/Baro sensor circuit high), and 78 (turbo wastegate solenoid fault). Don't really know anything about diesel engines, just bought this one recently, so any help is really appreciated.

txracer16

09-27-2003, 05:54

I have a 95 also and had the same problem. Mine was the wastegate solenoid ( or vacum switching valve) on the left side of the intake. Replaced it and light went away(after clearing codes). You will also find the vehicle performs better after replacing the solenoid because it controls turbo boost and if it is not working you have no boost. Do you get black smoke under acceleration? Mine did. Hope this helps.

whatnot

09-27-2003, 12:34

Before replacing the wastgate solenoid, you should check the vacuum pump and vacuum lines. All 3 codes will be caused by no or low vacuum. The best way would be with a vacuum gauge but you can get an idea by taking the hose off and see how hard it sucks.(with the engine running)

moose1

09-29-2003, 08:37

Whatnot,
I too have a 95 6.5 td ext cab. Being a newbie I am stumbling my way through learning about my truck. Could you please tell me where to test for the vacuum pressure. Also I have had no luck in getting codes from the DLC from my 95 any experience with that?