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Jeep delayed start - starting problems

Over the past 6 months, right after changing my fuel filter, I've experienced starting problems with my 93 Jeep Wrangler 4.0 liter. I had to crank it several times before it starts, so I thought. I just assumed that my fuel pump was on the fritz, but maybe not. I noticed that cranking it over several times is a complete waste of time. What I must do, is turn the ignition on, without cranking it, and wait for the check engine light to come one. This usually takes anywhere between 15-90 seconds. It seems to take less time if I keep turning the ignition on and off a few times, but really couldn't tell if that actually helps. When the check engine light comes on, I hear the fuel pump relay clicking like mad for a few seconds, than the fuel pump kicks in. After that, it starts right up the way it's supposed to. BTW, I've cleaned all contacts of fuses and relays, and the box itself. I tested the relay, and even swapped it out with a good one. I replaced the CPS and TPS, and cleaned the throttle body and passage to it, if any of that helps. I'm really confused about this one, so I hope that someone knows about this and can help me out. Thanks.

Reply to
Jesse
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Jesse did pass the time by typing:

Ok, first off, are you sure the filter was put in the correct way?

Second, the symtpoms you describe indicate the fuel pump is working but the system is draining. That could be a few things.

Leak at the filter connection. Leak at the fuel rail connection. Pressure regulator may have stopped working. Injector(s) may be leaking. The check valve in the pump has gone walkies.

.First check the filter.

With a cold engine! Then turn the key on then depress the check valve on the fuel rail. (you will want to have a rag handy) It should squirt out quite a bit of fuel.

The rest of the tests require a pressure gauge. An old R-12 is perfect for this job or you can buy a small one at a local parts store.

Reply to
DougW

You have electrical problems. The check engine light should come on immediately when the ignition is turned on.

I'd start by check>Over the past 6 months, right after changing my fuel filter, I've

Reply to
bllsht

I figured it out about two weeks ago. It was a bad PCM/ECM. I had to wait a while to get a check engine light. At first, the delay was 5-10 seconds, then 10-20 seconds. When it was over a minute that I had to wait for a check engine light, it became very irritating. Sometimes it even took 10 minutes. Once the check engine light came on, it fired up with no problems. From my research, I've found that the PCM energizes the ASD relay, which was not happening right away. When it was very quiet, I noticed a high-pitched squeal coming from the PCM. That was another reason to think it may have been the PCM. I think it was a leaky capacitor in the PCM, which took a while to store the energy it needed to energize the relays.

I really had to hunt around the internet for an answer to justify purchasing a new PCM, as they are very expensive, and incredibly hard to get a hold of a replacement. Make sure that it definitely is the PCM before purchasing, otherwise you'll be out about $300-$400 for no reason.

Reply to
Jesse

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