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4 Little Squirrels
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Subbed as mine has been slowly getting to this point :)
 

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Subbed.

When cold, mine takes several seconds to start and getting longer. When the engine is warm, it's just a twist of the key.
 

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I'm guessing the check ball in the pump is not holding pressure in the fuel line so the pump has to be cycled in order to build fuel pressure.
I think it runs rough shortly due to air in the fuel lines causing the engine to miss.
Brian
 

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I've been having the same problem on my 99 TJ! I tried the trick mentioned earlier and it worked! Obviously just a band aid but it's better that looking like I drive a heep... :)
 

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Might as well throw my two cents in there. I actually have gone from being able to prime my pump and it would usually go to having to turn it over at least once, sometimes twice. I've replaced my plugs, wires, rotor and crankshaft position sensor. For about a month after that she started no problem first try every time. Then one -12 degree early morning I barely bumped the key enough to get the starter to go and ever since it's been a two crank start. I've since replaced my starter (which was separately needed due to this I'm guessing.) Any thoughts or suggestions would be greatly appreciated.
 

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Bob97 and some others are right on with their suggestions. Mine does this, but I just cycle the key or let it crank. Pre-lubes the engine this way! Lol! There IS a check valve in the fuel system somewhere. It works like a foot valve on a well pump....it will KEEP the fuel in the lines and hold the pressure until it is started again. True....you MAY HAVE good fuel pressure....it just takes those extra 'cycles' to get the fuel BACK to the injectors. The Explorers and Rangers are famous for this as well. (I only know that from being a Ford guy! Lol!). Their check valve is built into the pump. Someone on the web was making a 'kit' that allowed you to install one without pulling/replacing the pump. Since I never had the need to research it yet, there MAY be someone doing it for our Jeeps as well?
 

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Cycling the fuel pump doesn't pre-lube the engine, the oil pump is only operational while the engine itself is rotating.

Regarding the check valve failing so the fuel pump has to be cycled repeatedly to get the engine to start, I was up to 8-12 cycles before my engine would start due to the leaky check valve and the pump itself finally failed Friday. Even after it started the fuel pump itself wasn't able to keep up & the the engine was running rough from not enough fuel... which generated a lean fuel condition in both banks (1 & 2). It was a crappy Spectra Premium fuel pump that barely lasted three years... that and Airtex are a couple brands that can't be trusted.

I now have a new Bosch fuel pump on order and it better make it here by Thursday as promised, I have a weekend wheeling trip I'm leaving for on Friday. Apparently Bosch is one of the OEM fuel pump manufacturers for Mopar so I'm hopeful it will last far longer than 3 years. :)
 

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Hi Jerry! Yeah...I was just being a smart ass! Lol! I meant it can build some OP while I just let it crank for 4-5 seconds or so until it fires! It means nothing...bad humor on my part. I do agree with your opinions on FP. I've seen the same thing MOST times. A guy DID put an Airtex in his F-150 against our advice....but wouldn't you know it....that's the one STILL running 5 years later and a ton of miles later! Bosch DOES supply a lot of OE mfgrs. Carter does a few as well.
 

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Discussion Starter #31
To all of you, I finally replaced the fuel pump again, and this totally resolved the issue. Damn I hate that. As a word of advice, remember the electric fuel pump in the gas tank is cooled by gasoline.

Allowing the fuel gauge to go into the red is inviting disaster from a burned out fuel pump. When it gets to 1/4 tank, feed it!
 

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Allowing the fuel gauge to go into the red is inviting disaster from a burned out fuel pump. When it gets to 1/4 tank, feed it!
Yes the fuel does cool the fuel pump but letting the tank get low doesn't hurt the fuel pump or make it run any hotter. It's not the fuel in the tank that cools the pump, it's the fuel passing through the pump that cools it. As long as the engine is running, the pump is being cooled no matter how low the fuel level is in the tank. If the gas runs out, the engine stops and so does the fuel pump. :)
 

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I think his theory is more fuel more heat sink as the heat has to go somewhere but since unlike the YJ 4.0 the TJ 4.0 does not circulate fuel to the rail and back to the tank there is no fuel warmed by going thru the engine compartment in the TJ tank
 

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I have a 1993 jeep and I have the following problem after three or four times of starting the engine, the engine starts. check the pump pressures and with the swtch on it has 5 psi, when it turns on (the engine starts) it has 28 psi and with the vacuum disconnected at the regulator it goes up to 37 psi.
 

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Fuel Pump ONLY PRIMES/PUMPS for a 2 second period each time the Ignition is turned to
the ON Position. To reach Pressure the system usually requires 6 seconds. Try an on and off sequence of → ON for two sec, then OFF, Back to ON for Two, Off one more time, THEN On --- Start. Bet that works for ya. I know-- a PAIN in the Hiniey for sure, but it's better than Cranking and Cranking with ALL the un-do wear and Tear on the Starter, not to mention the embarrassing LOOKS from people you get in the Mall Parking Lots.
Thank you Sir.
 
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