2010 Jeep Grand Cherokee 3.7 P0172 code

[Jcm1959]

Ok I need some help I have a P0172 code engine light flashing at idle white smoke and fuel coming out of the tail pipe. Last month I had the P303 code with white smoke and fuel coming out the tail pipe changed all the plugs which where in real bad shape everything has been great now this started I know it means it’s running rich and I changed the MAP sensor yesterday but no luck need to know what to do now can’t afford a mechanic thank you

[JPNinPA]

One or more of your injectors may be stuck.
This is bank one so it is in the front three cylinders.
Id check the wiring to the injectors. Make sure they are plugged in. Pull plugs to compare. The leaky injector will have the dirty plug.

Either replace the injector(s) or get it cleaned.

Also look if you have an exhaust leak. The engine will compensate by pouring more gas in.


Never look down on anyone unless you are helping them up - Jesse Jackson

[Jcm1959]

Thank you I appreciate the help I will check that out today and will post my findings

[Jcm1959]

I pulled all 3 plugs and #1 and #5 are pretty black even though they have less then 500 miles on them #3 isn’t as bad a little discolored not much so now I am wondering is this definitely bad injectors or something else causing it to run to rich

[Jcm1959]

Changed out the fuel injectors on the #1 and #5 cylinders these are the two with fouled plugs on bank one unfortunately then did not correct anything

[JPNinPA]

Still white smoke and running poor?

Did you reset the codes? You may need to reset so the LTFT long term fuel trim get reset.


Never look down on anyone unless you are helping them up - Jesse Jackson

[JPNinPA]

Pic of the plugs please?


Never look down on anyone unless you are helping them up - Jesse Jackson

[Jcm1959]

Not so sure resetting the codes will make it run better. It is running rough and blowing white smoke and extra fuel out the tail pipe. Nothing I have done has corrected anything. I cleaned the plugs and reinstalled them so I can’t give you a picture of them. I’m really at loss as to what to do next can’t keep throwing money at this and not get any results. I thank you for your advice

[JPNinPA]

The P0172 is bank one too rich. Causes can stem from: fuel pressure, injectors, exhaust leak, Vac/intake leak, dirty air cleaner, bad upstream O2, possibly a bad air sensor.




Never look down on anyone unless you are helping them up - Jesse Jackson

[Jcm1959]

Ok I understand that I guess my question is can any of these cause it to blow white smoke with excess fuel out of the tail pipe?? Also the air filter is new and clean, no exhaust leaks that I can detect, I can hear what sounds like a miss fire. Out of this list of possibles were do I go next not sure how to test for these things if there is any way for me to check them I would rather do that then rely on a mechanic I am not familiar with being new to this area I don’t know any of local shops or who is trust worthy not to mention the expense.

thank once again for your insight

[JPNinPA]

White smoke can be steam from a blown head gasket, burning oil from blow by past the rings or really rich condition. Being you said it is raw fuel and P0172 is why I suggested a stuck injector.
If you could get/borrow a noid probe to see injector firing and/or scan tool to see O2 readings that might help track it to a cylinder or general issue. General being too low or too high fuel pressure or wiring issue causing a stuck injector.
If a cylinder was not firing you would have a misfire code and the plug would look new/unused being you just changed them.


Never look down on anyone unless you are helping them up - Jesse Jackson

[Jcm1959]

Ok great that’s a place to start I can certainly get the scan tool for 02 readings not sure what a noid probe is but I’ll look into it thanks again let you know what I find

[JPNinPA]

Here is a good video with three different methods


Another for O2 info



Write the info down or take pics to share.

Never look down on anyone unless you are helping them up - Jesse Jackson

[JPNinPA]

Forgot about this... came across it today.

Testing Fuel Injectors Fast - YouTube


Never look down on anyone unless you are helping them up - Jesse Jackson

[JPNinPA]

There are these that are cheap $5 and work. And you don’t have to lean over a running engine.




Never look down on anyone unless you are helping them up - Jesse Jackson

[JPNinPA]

Not that this is your issue but is relevant to your engine.
Came in my feed this am and thought id share
Fixing a Jeep P0303 misfire - YouTube


Never look down on anyone unless you are helping them up - Jesse Jackson