I just bought a jeep wrangler with a 4 cylinder and 124k miles on it. My problem is on cold mornings it won, t start.I have to turn the key off and on to get the fuel pump to kick on. When the weather is warm it will start up with no problem. The guy I bought it from said I needed to replace the switch but I think it may be a relay. What do you think?
The relay should energize the fuel pump for 2 sec. When you turn the key on(does it) if it does and still no start, suspect fuel pressure. You should test fuel pressure. When is the last ime fuel filter was replaced.I would suggest start with a new fuel filter then re try(cheap piece to try). If still does it, on initial start have fuel pressure guage hooked up and see what pressure is(28-35 psi) if not cycle key(w/o cranking) again and see if pressure increases(if so) suspect fuel pump. If relay doesn't energize for 2 sec. You may need new relay/elec. Diagnosis. Ok try that let me know what you find