10-25-2019, 08:58 AM
Join Date: Mar 2008
Issues after fuel pump change.
Morning all. It's been a long time since I've visited the forum. The old Ram has been pretty good to me. Till now. A while back I had to replace the fuel pump. I needed it right away so I found one locally at Auto Zone I believe it was. Dropped the tank and replaced the pump. Right away I noticed it taking a second or two longer start. Then things got worse. After some time and especially in the mornings, it'll crank, fire then idle very rough for a while. Once in a while it would crank, fire, stall then fire right up. I figured possibly a bad pressure reg. on the pump so I intend to change it out again.
I'm also getting codes PO 128 (thermostat) and PO300 (misfire) and I'm most recently, losing mileage. Using the onboard computer as reference I've always had 11.4 around town and about 15-16 Hiway. Now I'm getting about 10 & 13 respectively. I'm wondering if if the misfiring could have damaged an injector or could a bad thermostat cause it to run that rich ?
I realize I need to check fuel pressure and as soon as I can borrow one and I will but does anyone have any thoughts or can point me in a direction to solve this ?
Thanks in advance for any help.
2005 Hemi Qcab 4x4
Billet grill (upper & lower).
Power wire. 4" homebrew cai (sprayed black w/ gold pearl).
Hemi-hat sprayed blk w/gold pearl & orange insert.
Taylor Thundervolt longs in red
Billet fuel door. replaced single disc player w/6 disc R.D.S. 2" soft dome tweeters added to dash. Halo plugs. 60" LED brake light bar. Whl-well liners. Stainless "Dodge" door sills. OEM molded mud deflecters. Manik s.s. taillight guards. Leer cap w/ in-cap mounted marine stereo & 1200 watt power inverter.