Truck Not Running

[jiminycricket]

hey guys,

ive posted a similar topic on here a few months ago and cant seem to find it. my truck is a 99 gmc sierra stepside, with the 4.8L. my truck went through some water and when i got home and turned the key off the horn stayed on and the signal lights flashed until the truck died. the security light is on on the dash and people say that will stop it from running but it came on many times before and ran fine. the truck only runs for about 4 seconds then dies. i checked engine codes and there were none. any suggestions would be great.

[markw8]

More than likely there are codes that don't come up on an ordinary code reader. Probably need a tech ll.

 

Mark