My 2007 Jeep Liberty Sport with 3.7 engine is hard to start when hot. It starts perfectly when cold, but is very hard to start when the engine is hot or the outside temperature is above 60 degrees Fahrenheit. It started around 140,000 miles and continues to be a problem. I’ve tested the fuel pump, replaced the fuel pump relay, and still no fix. My internet search results reveal that the 2007 Jeep Liberty is a part of the TIPM fuel pump relay problem that is defective on the TIPM control board causing hard starting. I have ordered a TIPM bypass kit from eBay that requires a fused tapped - jumper wire be installed between the Fuse 24 20 Amp Fuel Pump Relay (located in the underhood fuse box) and Fuse 3 20 Amp Cigar Lighter located in the passenger compartment fuse box. This configuration is suppose to bypass the defective TIPM and get you back on the road without replacing the unit or cutting any wires. Customers of the TIPM bypass cable say it is safe and will not harm any system or wires, and will keep your Jeep running and prevent hard starting and killing your battery if the fuel pump stays on when the ignition switch is “OFF.” Will it work? I’m certainly going to give it a try, because it has test procedures to determine if it is the relay, fuel pump, or defective TIPM, and this can be done by novice mechanics with little or no experience with auto electrical repairs.
Is this a safe bet or should I consider possible ECM driver failure? My research also reveal that overheated ECM that are located in the engine bay is a problem for 2007 Jeep Liberty vehicles. This maybe true when you consider that the problem is almost nonexistent in extreme cold weather. What a great ice storm we had this winter (2021) in Arkansas - no starting problems for nearly 10 days when the night temperature reached -3 degrees.
Hey let me know what you think?