6mpg indicates you have a bigger problem somewhere..... That is WAY outta line. How old are your O2 sensors?

 

New NTK about a week after the motor install. so prob month old. Ordered from Hughes.

 

Got a scanner you can plug in, and read data with? (not codes, data.....)

 

Get an inexpensive fuel pressure tester to verify. And how are you checking MPG's ?

 

No, dont have anything to read data. And I have a fuel tester just haven't put it on yet. I have to wait til I get home now. I check mpg by the odometer and gallons put in at the pump. Usually around the same. Before I did any work to this I was from 7-9 depending on how and where I was driving. Basically new everything. Used to have jet chip running 93 octane. Took it off for new motor and run 87

 

results of pressure test..video file was too large to post directly...

photobucket.com/fuelpressure

i know it's going to bounce but is that too much? and the pressure went to 42 when i turned it off and within a minute rested at 48 and dropped to where it is in the pic

how do those results look??

 

Yeah, fairly normal for an older pump, etc. Pressure looks acceptable though. If the Chrysler system is anything like GM systems.... there is a 'damper' in the line from pump, before it leaves the tank, that is supposed to smooth out those pulsations..... Yours looks like it's toast. I don't know if that would give you the symptoms you have though. Kinda expensive to throw a pump at it just to test.....

 

yeah it's unfortunate that they bunched everything up in the fuel tank. poor design. i've heard that some of the pulsation is from the injectors. could a couple bad ones cause too much of a drop? i only get the misfire on the two cylinders. i have new ones down there, might swap to troubleshoot but once i throw em in, i can't return them lol i just figured if it's something down the line i'd get troubles throughout, not just those two specifically

 

Pull the injectors off the cylinders in question, and inspect 'em. Merc had his clogged with crap..... also, ohm test 'em, and see what ya get. (spec is 12 ohms I do believe.....)

 

how much did they set you back? it might have been wiser to get a rebuilt complete set for like $140... otherwise the new ones may flow more than the ones you haven't replaced.. there are fuel screen filters in each one that can plug and impede flow. mine were plugged up .. you want them to all be even and a matched set.