Hard to start....


dangjalopy

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2000 Sahara, will turn over but will not crank. Sometimes takes 2-5 tries after the first start in the morning and then purrs like a kitten. All new injectors, fuel pump, CPS. Not sure about the fuel pump but it works fine after it does start so think it may be something different. I just bought this thing so not sure what is after market or OEM. I do know it has the banks monster exhaust and someone told me it could be vapor lock from after market exhaust. Any suggestions as to where to look. I feel by cranking as much as I have that the starter may give out soon. Thanks in advance for all the help.
 

CodaMan

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Vapor lock would not happen first thing in the morning, it only happens with heat.

It sure sounds like a fuel pump. Try turning on the key for a few seconds, then off, without cranking it, 2 or 3 times in the morning and then try to start it.
 

CodaMan

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Maybe the starter itself is on it's way out? Sounds like what my Jeep was doing a few months ago.

If it's turning over but not starting I don't think the starter could be an issue. Sometimes people need to use correct terms. I view "turning over" and "cranking" as the same thing, so I read his original post as "turning over or cranking" but not starting.
 

Jerry Bransford

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Since the engine is being cranked by the starter fine but not starting, (and crank does not mean 'start'), and it only doesn't start if it has been sitting a long period like over night, I'll say it's caused by a leaky check valve in the fuel pump assembly. And there are two check valves so both must be leaking... one is in the fuel pressure regulator and the other is inside the fuel pump itself. The check valves are there to keep fuel in the fuel injectors when parked for a fast start. When the check valves leak, that lets all of the fuel drain back down into the gas tank. The extra time it takes to start in the morning is how long it takes the fuel pump to get the fuel back up to the fuel injectors.

Simply stated, you need a new fuel pump assembly. Avoid like the plague store brand fuel pumps like from Autozone, O'Reilly's, etc. and avoid online brands like Airtex and Spectre as well. The last Spectre I installed lasted just 13 months, one month past its 12 month warranty expiration.

So unless you like dropping the gas tank repeatedly to replace failed fuel pumps, go with a Bosch who was the OE manufacturer for Jeep.

This one.... https://www.amazon.com/dp/B000BZJDK2/?tag=wranglerorg-20
 
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dangjalopy

dangjalopy

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I didn't install anything. The previous owner had them installed. I was thinking the fuel pump too because it seems my old TJ fuel pump acted the same way. It starts fine first start then after that....takes anywhere from 2 to 5 tries. Thanks. I only like OE equipment as well. Thanks again. About the cranking and turning over part...I am no mechanic but I understand how things work. If it's actually turning the engine...the starter is working correct? That is what lead me to believe it was something else. I guessed fuel pump but like I said...I ain't not mechanic. Thanks to all.
 
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Jerry Bransford

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Also, is it hard to drop the fuel tank for this repair?
It's not a difficult job for an earlier model TJ like yours. My '97 was pretty easy but my '04 is considerably more involved due to the increased number of plastic fittings for the frigging smog system. Just make sure your tank is as empty as possible before starting. I knew this from having changed my TJ's fuel pump before but I still managed to show up to mrblaine's house to install the new Savvy gas tank skidplate with a nearly full tank. He wasn't happy and I was just a little more than embarrassed since I knew better lol.

P.S. If you offroad, this would be a good time to also install a gas tank skidplate. What came under your gas tank is in no way a skid plate, it's just thin sheet metal.
 

Colin

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Apr 28, 2017
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Whangarei, Northland, New Zealand
Sorry to pouch on this thread but...
Mine has a similar problem but I don't believe it to be the fuel pump? Mine starts fine 90% of the time and runs sweet as. But every now and again it just won't start! I have to crank it over and over until it finally starts. Once I couldn't get it started at all so removed the crankshaft position sensor and replaced it with another one, still wouldn't start. Next I removed the distributor cap and rotor, there was a bit of dirt on the rotor so cleaned it up and cleaned the inside of the distributor cap. Assembled and tried starting. Started immediately so thought I had fixed the problem, then about a month later same thing, wouldn't start. Cranked it over and over until she fired and immediately ran sweet? This has only happened once when the vehicle was cold, rest of the time it was up to normal running temperature. Once after being switched off at the gas station after filling up? Any ideas guys?
 

Medali

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May 11, 2018
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Tunis, Tunisia
Hello everyone. The problem of the difficult start I had from the beginning, at the time of the purchase of the car. And since there are not many jeep specialists where I live, I have been diagnosed with a gas pump fault. And I was even sold a gas filter that turned out after the fact that it does not fit my model 2002 jeep and that I keep at home as decoration (as in the photo attached) .After when j I opened the tank and put the new pump (airtex), I realized that the problem still persists and that my jeep often starts on the second attempt (sometimes when the time interval is less than an hour) get it started the first time). So here I have two solutions that I have to do: 1 / I bought a check valve that I will try to install (I do not know where to put it to be effective) 2 / if with the check valve the problem still persists, I think I have to buy a pressure regulator (the one we put just above the tank)

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Lifted straight six

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Oct 26, 2020
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arizona
2000 Sahara, will turn over but will not crank. Sometimes takes 2-5 tries after the first start in the morning and then purrs like a kitten. All new injectors, fuel pump, CPS. Not sure about the fuel pump but it works fine after it does start so think it may be something different. I just bought this thing so not sure what is after market or OEM. I do know it has the banks monster exhaust and someone told me it could be vapor lock from after market exhaust. Any suggestions as to where to look. I feel by cranking as much as I have that the starter may give out soon. Thanks in advance for all the help.
Sorry to chime in on and old thread, but I have almost the same problem, I checked fuel pressure, and everything reads fine. Did you fix it? If so, how?