strange problem?

the other day i was sitting at a red light and my 95 (5.7-4l60e) truck lunged forward a little bit like someone stepped on the gas. i noticed that the rpm's went from 550 to about 900. i put the trans in neutral and they went up to about 1000. put it back in drive and it shifted kinda hard. drove down the road and the shift points were higher. doesn't do this all the time just every now and then. could the problem be a torque converter clutch solonoid or maybe a pcv valve? any help would be greatly appreciated. sorry this is so long but needed to explain everything.


thanks mike

the other day i was sitting at a red light and my 95 (5.7-4l60e) truck lunged forward a little bit like someone stepped on the gas. i noticed that the rpm's went from 550 to about 900. i put the trans in neutral and they went up to about 1000. put it back in drive and it shifted kinda hard. drove down the road and the shift points were higher. doesn't do this all the time just every now and then. could the problem be a torque converter clutch solonoid or maybe a pcv valve? any help would be greatly appreciated. sorry this is so long but needed to explain everything.


thanks mike

this is usually a vacuum leak . if you create a vacuum leak [for testing] you will see rpm go up. look over all vac lines esp. the PCV replace all that are hard and cracked if someone used carb cleaner this destroys rubber parts over time use vac guage. always buy more vac line than you need you'll always need more than what you think you need.

theres always a chance on old vehicles like yours that the brake booster is going.............

hey, thanks for replying. i think you are right. that is the first thing i checked and i found that the hose going to the pcv valve was cracked. i justr taped it up cause i haven't had time to get to the parts house yet. i drove it for awhile today and it seemed to do alright. i am going todrive it for a few days and see how it does. maybe that was the problem.

thanks again mike