Starting Delay?

My '91 XJ takes forever to start. It had this problem with my old engine, OEM 4.0L, but I got the engine replaced because of weak oil pressure/bad cylender. It was replaced with a '01 HO 4.0. It still takes a very long time to start, and I am wondering what causes this. I can hear my fuel pump come on, and even if i let it pump for a few seconds prior to the crank attempt, it still takes a while (10-15 seconds).

Any suggestions?

Adam Duncan said:

My '91 XJ takes forever to start. It had this problem with my old engine, OEM 4.0L, but I got the engine replaced because of weak oil pressure/bad cylender. It was replaced with a '01 HO 4.0. It still takes a very long time to start, and I am wondering what causes this. I can hear my fuel pump come on, and even if i let it pump for a few seconds prior to the crank attempt, it still takes a while (10-15 seconds).

Any suggestions?

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You might be loosing pressure. Try this: when you start the engine finally, turn it off and then immediately try to start it up again. If it starts without the delay you most likely have a problem with either a check valve or a pump that allows the fuel to drain from the engine back into the tank, so that when you're trying to start it up again it has to repressurize (refill?) the whole system. I had that problem when I had the dealership "fix" my fuel sender unit.