KJ Multiple Problems.

ZiadK

New member
Hello Jeepers.
My jeep is giving me nightmares, i have been trying to fix it for 2 years no hope yet. anyway i will state my problems here i hope you will help me, they are too much but meh please help.
1- my jeep fuel cusumption is 7MPG YES 7MPG, NO i'm not LYING. i tried filling the car till F and drove around till it reached E and the result is 155.343M (250KM) which is 7MPG.
2- my jeep is emitting white smoke from the exhaust, while idling there is no smoke, while going slowly there is no smoke, only on kick down or while pushing the pedal hard a white smoke appears and goes away after a little.
3- my jeep dies while going uphill, what ever my car speed is when i reach an uphill my jeep starts to die till it reach the 2nd shift. for example: if i'm going 160 on a highway then an uphill appears the jeep wont go fast keeps going slow it even if i push the pedal it keeps dying till it reachs the 2nd shift then it takes it force back and when it reachs 3rd shift it dies again, i don't know if you got the idea.
4- VERY HIGH OIL CONSUMPTION, i add ~ 1Killo of oil each month!.

what i did:
1- Replaced the fuel filter.
2- Replaced the air filter.
3- checked the catalytic converters.
4- made a compression test the jeep result on all the 6 spark plugs is 145PSI
5- checked transmission system
6- checked the front and rear differential
7- checked all the seals (oil seals) for any leak!.
8- Replaced Spark plugs brought original mopar spark plugs.
9- Fuel pump is in good state compression test result is 50PSI.
10 - Cleaned the IAC and the TB.
NOTE: Check engine light is off.
Thank you, your help is really appreciated.
Best Regards!
 

Welcome to the board!

Sorry to hear of your troubles.

What year jeep?

For the mileage 153 miles what is the actual gallons? Full doesn't always mean a full 19 gal. Though I believe you may have a real issue with the mpg so far off.

The white smoke is a sign if it is past the first 3-5 min of warmup. Is the smoke moisture or oil? You could tell two ways. Color white or white with a blue hue. And by placing your hand in the exhaust stream to collect some of the smoke. Does it feel oily?

Your oil consumption is per month but what is it per mile? There can be small amounts of loss but more than a quart every 1k mi is higher than average.

Even though your check engine light is not on there could still be a code stored. Try the key off on three times and look at the odometer for any codes. Ie P0XXX

How did you check the catalytic converter?

What did the spark plugs look like when removed?

Do you have larger than stock tires?
 
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Welcome to the board!

Sorry to hear of your troubles.

What year jeep?

For the mileage 153 miles what is the actual gallons? Full doesn't always mean a full 19 gal. Though I believe you may have a real issue with the mpg so far off.

The white smoke is a sign if it is past the first 3-5 min of warmup. Is the smoke moisture or oil? You could tell two ways. Color white or white with a blue hue. And by placing your hand in the exhaust stream to collect some of the smoke. Does it feel oily?

Your oil consumption is per month but what is it per mile? There can be small amounts of loss but more than a quart every 1k mi is higher than average.

Even though your check engine light is not on there could still be a code stored. Try the key off on three times and look at the odometer for any codes. Ie P0XXX

How did you check the catalytic converter?

What did the spark plugs look like when removed?

Do you have larger than stock tires?
Hello, and thank you!

first of all i have a liberty sport 2003 V6 3.7.

I filled the jeep till the F, till the fuel pump machine made a tick sound (indicated that the fuel level is maximum) then drove around till the low fuel signaled on, and checked my odometer and it showed that i drove around for 250KM.

No i'm not talking about the warm-up session, after the warm-up the jeep faces this problem, i need to test the method you said about putting the hand i will try it today and reply you, but i think its oil smoke.

i never calculated per mile oil loss, but i'm sure its not normal because I'm nearly filling 5 litters (even more) of oil between each refill dead line.

yeah i tried this method and used the OBDII to check if there is any old codes, nothing is appearing.

i checked the catalytic converters by making a screw before where they are placed and tried to drive around, performance didn't change.

The Spurk plug heads had black head, i don't know if its signal of mixture of oil and petrol, or mixture of water and petrol, but i think its not water and petrol because the water level never goes down.

no i have stock tires, they are not in a good shape i admit, i'm gonna replace them soon.
 
Ok You really need to divide miles driven per gallons pumped. Running from full tank to empty. I've calculated up to a 25% error in mph by refilling after only a few gallons consumed. You could sometimes squeeze another gallon in by topping off. Second if you had a dent in the tank or expected a 19 gallon tank and only have 14 gallon will result in an error based on how you calculate. Third, based on the station some gas pumps kick off early or you may have a clogged or dented breather vent on the fill tube causing it to kick off before the tank is really full.
And many times I see I'm below E but there is still 2-4 gallons left cause I end up pumping 15-17 gal of the 19 gal tank.

Black spark plugs could be burning oil but you state the compression is consistent between cylinders and 145? This is good pressure and you unlikely have blow by.

The issue can be one or many stuck injectors.

I'm not sure I follow how you tested the catalytic converter. You could unscrew the O2 sensor up front before the CAT on the engine side. Then run the engine to see if there is still a loss of power. Be sure to not damage the O2 by securing it to the vehicle. A bad O2 can cause a rich mixture but not a 4mpg issue typically.
 
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The issue can be one or many stuck injectors.

I'm not sure I follow how you tested the catalytic converter. You could unscrew the O2 sensor up front before the CAT on the engine side. Then run the engine to see if there is still a loss of power. Be sure to not damage the O2 by securing it to the vehicle. A bad O2 can cause a rich mixture but not a 4mpg issue typically.

Okay how can i diagnose if there is stuck injectors ?

about the test of the CAT Converters, i screwed just before the CAT Converters. so the air going from the engine doesn't go inside the CAT Converters anymore they just exit the screwed place, after that you can hear the real sound engine :p, and drove around to see if things changed, power etc... and everything stayed the same.
 
Throwing ideas out there. White smoke to me indicates your head gasket along with oil consumption and no leak found. But still take a good look for illusive leaks, t-belt and cover, gaskets ect. Take a good look at oil, greenish bubbles on dipstick will indicate coolant in oil and check coolant fo oil in it. Is it over heating at all? Could also partly cause of fuel issue along with vacuum line leaks(take a good look for cracked, damaged, rotting line, very common for causing bad fuel consumption) and driving 160 on a highway. Assuming mph? that's crazy man. Possible timing is out as well. I would check with a gun to verify.
 
Throwing ideas out there. White smoke to me indicates your head gasket along with oil consumption and no leak found. But still take a good look for illusive leaks, t-belt and cover, gaskets ect. Take a good look at oil, greenish bubbles on dipstick will indicate coolant in oil and check coolant fo oil in it. Is it over heating at all? Could also partly cause of fuel issue along with vacuum line leaks(take a good look for cracked, damaged, rotting line, very common for causing bad fuel consumption) and driving 160 on a highway. Assuming mph? that's crazy man. Possible timing is out as well. I would check with a gun to verify.

Hello, i checked all the illusive leaks, replaced all those seals, there is no more outer leaks or illusive leaks

There is no mixture of oil and water or gas and water, and there is no overheat signs.

Could you please explain what do you mean exactly by rotting lines and if you can provide me a tutorial how to check them, thank you
 

Stuck injector

Different vehicles but similar method.





You can use a stethascope to listen to each injector. They should make a rapid clicking for every spray of gas. The one that doesn't is your bad injector.

You can put a fuel pressure guage on it and see if the fuel pressure drops after you turn the key off, but the loss of fuel pressure could be a couple other things too. Most of the time a stuck open injector will flood a cylinder bad enough to get raw fuel out of the exhaust (white smoke, smells like raw gas) And a spark plug that is either severely black or wet with gas. Other than that you can pull up the fuel rail with the injectors attached and have a buddy cycle the key on and see if any are leaking fuel.
 
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Stuck injector

Different vehicles but similar method.





You can use a stethascope to listen to each injector. They should make a rapid clicking for every spray of gas. The one that doesn't is your bad injector.

You can put a fuel pressure guage on it and see if the fuel pressure drops after you turn the key off, but the loss of fuel pressure could be a couple other things too. Most of the time a stuck open injector will flood a cylinder bad enough to get raw fuel out of the exhaust (white smoke, smells like raw gas) And a spark plug that is either severely black or wet with gas. Other than that you can pull up the fuel rail with the injectors attached and have a buddy cycle the key on and see if any are leaking fuel.

i saw these videos on youtube, okay i will test them methods you provide it soon.

i don't smell raw gas from my exhaust it smells like something burning plastic or metal, the smell is really bad, thank you.
 
Hello, i checked all the illusive leaks, replaced all those seals, there is no more outer leaks or illusive leaks

There is no mixture of oil and water or gas and water, and there is no overheat signs.

Could you please explain what do you mean exactly by rotting lines and if you can provide me a tutorial how to check them, thank you

Vacuum lines can get old, soft, cracked and cause vacuum leaks by a poor seal and can definitly cause poor fuel mileage. As simple as inspecting them
Not that this is your issue but as a example I replaced seals/gasket in my throttle body because of vacuum leaks, on my laser, just replacing my tb shaft seals gave me almost an extra 100 km out of a tank is fuel. Vacuum leak was just a thought to your fuel issue weather its lines or seals and gaskets. Something to look at
 

Vacuum lines can get old, soft, cracked and cause vacuum leaks by a poor seal and can definitly cause poor fuel mileage. As simple as inspecting them
Not that this is your issue but as a example I replaced seals/gasket in my throttle body because of vacuum leaks, on my laser, just replacing my tb shaft seals gave me almost an extra 100 km out of a tank is fuel. Vacuum leak was just a thought to your fuel issue weather its lines or seals and gaskets. Something to look at

Okay Thank you i will look at them!.
 
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