really bad fuel economy

[06hemixk]

http://media.chrysler.com/newsreleas...id=9117&mid=18

[martin.steve]

i sent an email to both of those contacts and they both got back to me, they took my vin and home phone number and are submitting a work ticket to investigate the problem, so with any luck ( fingers crossed) they will get back to me with some sort of answer. thanks 06hemixk, youve been so helpful so far!

[06hemixk]

Not a problem Martin. Hopefully that will get you further than contacting the dealer and having them charge you for silly diagnostics. Plus they have a lot more "pull" being in corporate if you do need some work done.

[martin.steve]

well yeah cause really i kinda feel like now its at the point where it should not be my dollar spent to solve the problem since diagnostics and trusting the mechanics to figure it out hasnt worked, not to blame the mechanics at all just sayin , if they cant figure it out then what else can a person do ?

[Eric S]

Wow that is horrid efficiency. Hope you can diagnose it soon.
It is odd that you are not getting any codes thrown with such crappy mileage. I assume someone has checked for fuel leaks? A compression check would be a good place to start as well just to rule out the mechanics of the engine. Also, like was said a full tune up is in order. Doubt new plugs fluids will fix the problem but it swill help a bit and should be done anyway.

[Eric S]

For some added info, there are two codes that are thrown if the Hemi is stuck in open loop:

P1129-CLOSED LOOP FUELING NOT ACHIEVED - BANK 2
P1128 - CLOSED LOOP FUELING NOT ACHIEVED - BANK 1

Enable conditions are met and the 02 sensor has not been in closed loop control at least once on each of the two consecutive trips, the MIL illuminates and the DTC is set. Two Trip Fault. Three good trips to turn off the MIL

Originally Posted by martin.steve

... having them probe it to check the gas levels of the exhaust, i have yielded no results.

Do you trust them on this? Pretty sure this would mean that you HAVE to have a fuel leak somewhere. 16L/100km more than my Hemi is burning, can't see how it could burn it and not be running rich. (for reference I am usually around 17-18l/100km)

Originally Posted by martin.steve

...according to the computer monitoring system its saying im getting 21.9 ltrs per 100 kms which is crazy even for the hemi. mine is an 06 5.7 aswell, the last tank i went 203 kms on 70 ltrs so that about 112 miles on 18.4 gallons i

12.6l/100km difference between the the ecm's calculations and actual. Maybe another indication of a leak. Do you get further on a tank if the Jeep sits less?

[JBenn911]

Pleas don't laugh too much, but... Have you verified that your speedo, or more importantly odometer are reading right ?? I know wheel and tire change will throw your odometer and mpg readings off, not to the degree you have, but it could be one more thing to look at

[martin.steve]

no at the end of 200 klms the tank is definatly empty lol

[JBenn911]

oh, i dont doubt that, was just wondering if its actually 200km being driven or more, like 300-350 or something and your odo was reading it off..it was a stretch, just tossed it out there..lol

[martin.steve]

so heres the diagnosis, its been fixed. it was a failing coil pack not providing spark to the last two cylenders, but somehow not rripping an error code??? and weve now changed oil and air filters, and new spark plugs.(the plugs in it where original factory plugs from 2006 lol) i hit the highway yesterday and got her all the way down to 14 ltrs/100 kms so between the failing ignition coils and the complete lack of mainenance from the previous owner, basically it was just running like crap. i still cant figure out why it didnt have a dtc but who knows. Thanks everyone for the advice, help and general well wishing especially 06hemixk!