Alright, well my truck is shifting fine and aint leaking fluids, but i got this hissing sound that seems to be coming from the front driver side area. That faster it goes the louder it gets. It dives fine in town (other then the hiss) but when i get on the highway going about 60 itll start to slow down, it went from 60 to 50 without me moving my foot until i tap the gas, then itll get back up to speed and start all over.Im hoping i just knocked an air hose loose when i was changing the plugs but it sounds like its coming from underneath. cant check nothing till tomorrow. The only thing ive done to it(other then drive it) is change the plugs and wires. The wires were from a different car but i cant see it having that kind of effect. Well I appreciate yalls help.

 

Check the vacuum line for the cruise control. The cruise module is under the battery, so, that may account for your hiss. Maybe....

 

Well the cc vacuum line looks to be okay, cant see or feel any leaks in it. But i do got a few things to add. i started messing with it today and noticed that i cant hear the leak while its in park. But i can when its in drive and i hold the brakes and rev it up(Barely). but i did notice white smoke coming out of the oil pan gasket. Would that cause the hiss and the power loss or just another prob all together. I also got a clogged up cat and some small holes round the intake gasket. i was thinkin that maybe the cat finally pluged up and is pushing the exaust out them holes harder then before, would explain the hiss but would it explain the power loss? I appreciate all yalls input. Oh yeah, and it idles and revs up just fine when it aint moving. Oil pressure and temp gauges seem to be fine.

 

Clogged cat will contribute to all of your symptoms. Pull the O2 sensor out of it, and take it for a ride. That will tell the tale. (of course, it will be loud too....)

 

so i unhooked the o2 sensor and It did help, but didnt solve the problem. Now it still has the hiss, which i figure is exhaust leak up near the manifold. but now when i get to round 50 my rpms will bounce between 1800 and 2100 and i can move my foot almost an inch with no effect. if I tap it a bit i can get it up to 60 but then after a couple of min the engine will go quiet like i let off the gas and start to loose speed, then about 10sec later itll jerk and start going again. Any other ideas?

 

Did you unplug it, or remove it from the cat?

 

unhooked it from the cat.

 

I would ask if you can still hear the fuel pump, but, I doubt it, (even if it IS still running. )

Maybe ASD or fuel pump relay?

 

Right, even with the o2 plugged in. I got half a muffler and no tailpipe!! But Ill check them out tomorrow. And I appreciate the help man, Im stumped. Im probably gonna take it to the shop if I dont figure it out by next week.

 

well i checked the relays and there all clicking just fine. im gonna try putting my old wires on it and see if that help. (Prob not but im running out of ideas). Feel free to keep throwing them at me!! I aint looking foreword to the shop bill!!! and i know my cat is bad and unhooking the o2 helped a bit, so you think even with the o2 unplugged it still aint pushing enough out?(I know its a big hole, just spit balling) You think cutting the cat off all together could help?