99 backfires

[1980dg]

yes white plugs lean i do not run the jeep only to test it after i change somthing All the plugs were white i dont think it is a leaky injector i dont smell gas but like i said i will run the tests vac fuel pressure change around injectors tomorrow and let you guys know from there

 

[winterbeater]

To find intake leaks, you can take an unlit propane torch and go around potential intake leak areas while listening for rpm changes.

While you're at it check for intake leaks.

 

[1980dg]

yea will do thankyou

 

[1980dg]

when i put the code reader on it after hooking the battery up i no longer had a injector 1 and 3 code so i took it for a run ran bad bad like a wild horse when i came back i could hear a small air leak sounded like from the intake so i pulled it and looked at the gasket looked good hooked it all back up. befor that i had a tick tick tick from my purge silinoid evap thing it had been makeing that tick tick tick for about a week i had just unpluged it the wires that is well today i hooked it up and figuered out that when it was makeing that tick tick tick it was opening and closeing witch it should but only if fuel vaper pressure exseads 1psi and was makeing like a vac leak maby well i pluged the vac side and let the fuel pressure vapers just vent openly well i took it for a ride and runs good real good no backfire so can some one explain what i could have done to to help it the only code i am getting now is p0100 somthing about maf or vaf i am thinking that that is for the evap systom let me know what you think i cant spell im sorry thank you

 

[winterbeater]

Everyone says that the purge solenoid is supposed to tick tick tick almost all the time. I wonder if you have a damaged charcoal cannister or the lines that suck the fumes. I had a cracked cannister on my Crown Vic that made it run leaner and leaner over time until I replaced. I was getting 36 MPG, but figured I might burn a valve if I didn't fix it. Maybe the purge valve is bad, letting in too much air. Not sure what the code is.

 

[1980dg]

well when it tick it opens allowing the vacum to suck the vaper out in the manual it says it only opens when there is pressure on i can unhook the fuel vaper side and it just sucks sucks sucks air i dont know but i will trace the lines all the way back and check the coal can and line i didnt think that far a head i dont know but if it always sucked tick tick tick than wouldnt that make a negitive pressure in your fuel tank i have heard of a lot of backfire issues with 99 cherokee sports and not to many fixes

 

[winterbeater]

Checked out FSM on this issue. During closed loop (not warm up or hot start) operation, the solenoid is supposed to cycle 5 to 10 times per second with pulse width controlled by the PCM. Which manual are you looking in? This sucks the fumes out of the charcoal cannister, not the fuel tank, so it does not create a vacuum in the tank.

 

[1980dg]

ok i will do some digging on it thankyou but theres somthing wrong with it i know there is you can here it from the cab wile driving nonstop and loud like its freaking out i didnt get to far into the manual today i drive 45 min to get to my building so i stopped when the snow started falling to come home and ask q and read

 

[winterbeater]

I agree that something is wrong, and I'd drive it disconnected until I figured it out. Maybe plug it in once or twice a week to keep the cannister from getting saturated. You don't want to fry a intake valve.