Auto pilot

[GARY BRUNGARD]

Hey guys I have a 98 Z71 K1500 and while driving down the road my truck seems to be still accelerating and when I get into traffic it does become a problem it is like power braking you want to stop but the truck wants to keep going. One thing I did figure is when I start up the truck and put it in gear I have to wait for the rpm to drop down to 600 from the initial almost 900rpm while in drive standing still waiting for it to drop. Some times when I put it in gear you can here the rpms go up a bit so while in drive I have to wait for it to come down before I can drive.

[16th hippy]

just to make sure i am understanding you right, it's not as if the trans is slipping, but the engine is revving up a bit and trying to make it go even with brakes on? might wanna check throttle body for being dirty, and check throttle cable(s), especially cruise control. might need to be adjusted. and check the pedal area to make sure nothing is binding or jammed up in there.

[GARY BRUNGARD]

The trans dosent slip at all. When you start the truck up it idles about 900rpm cold, then you put your foot on the brake still rpm stays the same then you put it in gear while foot is on the brake you can feel the truck suddenly surg a bit like your two peddling it and you have to wait for the rpms to come down sometimes. Another thing I noticed is when driving down the road I would take it out of gear and the rpms would go to about 1800rpm WTF!

[16th hippy]

well, check the throttle for issues as suggested, and also check for vacuum leaks and let us know what you find.

[GARY BRUNGARD]

Thanks for the reply, the weather is really crappy and sunday is the superbowl so I will check it out on monday oyea when I went home from work yesterday I warmed it for about 10mins before driving it and waited when putting it in drive and no problems. I dont know but I did put in a 130deg stat in?

[777stickman]

Originally Posted by GARY BRUNGARD

I dont know but I did put in a 130deg stat in?

And you put a 130 stat in for ???? I know I'll get some heat for this from some of the other guys, but. Todays computer controlled engines require a 195 deg stat. The computer needs to see the engine operating temp up around 185-190 for everything to work as designed. Just My Humble Opinion.

[GARY BRUNGARD]

I thought like it said when I bought it would make a little more power or somthing I dont even remember anymore it does run cooler in the summer but do you really think it could leed to other problems?

[rockwood84]

check the iac and tps but why put a 130 degree t-stat in. some engines use coolant around the throttle body to make them run better .this could be what is causeing the fast idle as throttle body operating temp too cold.a bad tps will make it usually idle too low or unsteady. but have seen some stick and make it idle high. the iac if it is dirty or sticking will make the idle run high.did it do this before you put the 130 degree t-stat in?

[GARY BRUNGARD]

No it never did this before I put it in and its kind of funny now that I think about it I warm up my truck for at least 5mins before driving it and the probleme dosnt seem to be as noticeable when I put it and drive while having my foot on the brake, it barely needs to drop in rpms before driving.

[16th hippy]

go back to the 195deg stat for starters.....fricking autozone sold me a 180deg when i told them 195....punks....and i think it was mis-boxed cause it only warms up to about 160.

[rockwood84]

yeah i would go back to the 180 or 195 t-stat because some emissions systems use the coolant to warm the throttle body and if you have a 130 degree t-stat in its gonna throw the system off and make things get screwed up.and do not put a t-stat that is made in mexico in because i have found they won't open in boiling water. i put five in and ended up pulling the five back out because they didn't act right the last two i boiled some water and set the pan aside and dropped the t-stats in and they never opened.i'm guessing the other three didn't open either, but i noticed all five were made in mexico. so i got to looking for a t-stat made in usa and they are hard to find. finally after 10 parts stores found one made in usa put it in no problems

[GARY BRUNGARD]

Thanks for all the replies I am definitally going to put back the correct stat made her in the USA and while I was overlooking the job I noticed the intake manifold gasket is leaking antifreez ever so slightly in the back by the distibutor so it looks like I am going to be doing a little bit more work never fails.