white crow

truck runs for 5 mins then it runs horrible the intake makes a lous sucking noise and it revs on its own smells like raw fuel any ideas??

98jeepsrt6

need some more info but from what ur saying it sounds like a vacuum leak.. and ur fuel smell could very well be ur upstream o2 sensor.. But like i said need more info.. what engine which i assume is the 4.0 also what other symptoms to you notice?

white crow

its a 4.0 it runs fine for awile at idol then it runs bad usually after 5 mins . and when i first start the car it dosnt matter how long it idols for when i start to drive it in like 100 yards it runs like crap then it clears up . i got my computer scanned and my upstream o2 sensor is bad i thought that would just give me bad gas mialage could it do that too ?

98jeepsrt6

yes that can happen, i actually just resolved that issue.. but mine was sooner then five minutes... mine was at 60 sec.. when you hit the gas everything seems to be normal again..??

white crow

yea its like u gotta clear it out tho and then it runs perfeclty fine .

98jeepsrt6

yea, mine was happening at the point when our jeeps go from open loop (at warm up it runs rich) to closed loop (normal o2 operation)..

I had to extend the o2 wires since my new headers and down pipe made me move it further down the exhuast stream.. I think there was a delay between the wires or some crap.. idk

After i completed the exhuast i had the shop move my o2 sensor further up and i also put in a brand new one, problem solved..

ok enough of me... Any updates yet?

white crow

everythings still the same it just snowed up here in ny so i cant really work on it i wish i had a garage lol i would be fixed already

white crow

i put an o2 sensor in today hopefully that will give me some better gas mialage but it still runs bad if i leave it idoling for a little bit it runs good then like 2 mins goes by and its like its dumping too much gas in the motor my friend said it might me my iack valve ( idk how to spell it ) lol. he said it just needs to be cleaned . i dont have a clue what the iac valve is ether

spiceman

its easy to clean, get some brake clean and remove it from the throttle body and spray it down and all around in the tb. then let it sit for a min to evaporate and then put it back in. might solve your problem, its a cheap fix

the hardest part of it is having to go and buy some torx bits if you don't already have them lol....