The last couple days my truck has been running weird. The engine has been surging randomly while I am driving. Also the engine will start running rough after I start it, especially if it has just been run a few minutes prior. The engine has also started to run rough at a normal idle several times.
Just a little under 2 years ago I bought a return line kit and installed that. I do not see any visible signs of fuel by any of the injector caps. Also, I have a racor fuel/water separator and I do not see any fuel leakage elsewhere in the system. I also replaced the lift pump less than a year ago.
Before I installed the current return line kit, I was having problem with rough idle, but it would clear up after a 30 sec or so of running. This is the first time I have had the engine run like this after driving for a bit. Does this seem like maybe I need a new return line kit again, or could there be something else that I am missing?
Just wondering if anyone has any input on my problem? I am thinking that I will just plan on purchasing another return line kit and go from there. My biggest concern has been the engine surging and rough idle after it has been running for a few minutes. I never had that happen before I put in the current return line kit. Before I installed the current kit, I was only having problems with rough idle and stalling right after I started the engine.
I wouldn't concentrate on the return lines, but rather check all potential sources of air intrusion. Fuel heater O-rings, WIF sensor, return lines & caps, etc. You might save yourself the hassle of doing return lines. Or you may find that the return lines AND something else are letting air in.
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1990 Jeep Wrangler Sahara, in the process of a major overhaul/upgrade. OM617 on the horizon! Front & rear Dana 44s from a Wagoneer till I get some 1-ton axles built & narrowed, and eventually a front shackle reversal. Diesel YJ, bay-BEE, and not a cookie-cutter 4BT conversion!