2000 TJ long start issue

[daltonsears]

Hey guys, I’m new to this forum but I’ve been dealing with a starting issue for a while now and I can’t seem to de-bug it.

2000 Jeep TJ 4.0 Sport

I’m having long start times, 8-10 seconds of cranking before it turns over. After researching a tad, I’ve replaced the Fuel Pressure Regulator (twice, thinking I got a defective first one), replaced the Fuel Pump Relay, new plugs, but it’s still taking longer than normal to fire up. Is it a drain back issue? Do i need to replace the whole fuel pump assy? Any advice is appreciated!

 

[pagrey]

You might get a fuel pressure gauge and see if you are loosing pressure as it sits. Leaking injectors can bleed down. You could just pull them and see if they are wet. You also might check the ignition switch, sometimes they fail so that on crank the ignition power shuts off although this is much less common. I wouldn't go into the tank again without taking a look at what your fuel pressure is really doing.

 

[Chris]

You may need to replace the entire fuel pump assembly, as this sounds like it could be related to the drain back valve (which is part of the fuel pump assembly).

If you cycle the ignition a few times (turn the ignition on without cranking it, let the fuel pump prime for a few seconds, then turn the ignition off, and do this multiple times), does it then start right up?

 

[daltonsears]

You may need to replace the entire fuel pump assembly, as this sounds like it could be related to the drain back valve (which is part of the fuel pump assembly).

If you cycle the ignition a few times (turn the ignition on without cranking it, let the fuel pump prime for a few seconds, then turn the ignition off, and do this multiple times), does it then start right up?

No, I’ve tried that trick and it still doesn’t start right up.

 

[daltonsears]

You might get a fuel pressure gauge and see if you are loosing pressure as it sits. Leaking injectors can bleed down. You could just pull them and see if they are wet. You also might check the ignition switch, sometimes they fail so that on crank the ignition power shuts off although this is much less common. I wouldn't go into the tank again without taking a look at what your fuel pressure is really doing.

That was my next plan to pull injectors and possibly replace them.

 

[pagrey]

You might take a close look at the gauges when you crank the engine, if the ignition switch is causing problems the cluster will turn off or behave erratic when you crank. If you cycle the key and it doesn't help I don't think it's the injectors. You could pull them and take a look but I wouldn't replace them. Maybe just the o-rings.