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Discussion Starter #1
  1. Okay I am new to this page so I am hoping this is in the right discussion area. I have a Jeep wrangler Sport 2002. It shows it has no fuel on the dash and will not start, even though there is 3/4 of a tank at least. When I lean on the rear driver side fender it, engages and shows it has fuel and will allow you to start it as long as you are leaning on it. We have checked all the grounds and such, and it is at a mechanic shop. We replaced the computer due to the fact the scanner couldnt communicate with it. But that has fixed nothing. Thank you in advance.
 

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Jeep G. Cherokee
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Something electrical is wrong. When you lean on it, it must un-short whatever is wrong.
 

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03 WJ, 4.Slow, 3" IRO
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  1. Okay I am new to this page so I am hoping this is in the right discussion area. I have a Jeep wrangler Sport 2002. It shows it has no fuel on the dash and will not start, even though there is 3/4 of a tank at least. When I lean on the rear driver side fender it, engages and shows it has fuel and will allow you to start it as long as you are leaning on it. We have checked all the grounds and such, and it is at a mechanic shop. We replaced the computer due to the fact the scanner couldnt communicate with it. But that has fixed nothing. Thank you in advance.
On the 32 common problems on the WJ page item #2 answers your issue.

2. Problem:*Engine cranks but will not start. May have died while driving. Related symptoms: Fuel gauge shows 'empty', however the fuel tank is not empty. Volt gauge is all the way to the left (low), but the battery is not discharged.

Cause:*The CKP (crankshaft position) sensor is shorted internally. Turn the key off. Unplug the CKP sensor and retest for proper gauge operation.

Fix:*Replace the CKP sensor to correct.

Notes:*Scan tool will show 'no response' to PCM (engine computer). This is why the fuel gauge and volt gauge are inoperative. The PCM is not functioning, so the fuel and voltage data is not bussed to the instrument cluster. When the the CKP sensor shorts internally, the PCM will not function. The connector is located on the right side of the engine, near the rear of the engine block. The CKP sensor is located on the left side all the way in the back. Usually it must be replaced from under the vehicle. This is a fairly common problem.
 

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Discussion Starter #4
On the 32 common problems on the WJ page item #2 answers your issue.

2. Problem:*Engine cranks but will not start. May have died while driving. Related symptoms: Fuel gauge shows 'empty', however the fuel tank is not empty. Volt gauge is all the way to the left (low), but the battery is not discharged.

Cause:*The CKP (crankshaft position) sensor is shorted internally. Turn the key off. Unplug the CKP sensor and retest for proper gauge operation.

Fix:*Replace the CKP sensor to correct.

Notes:*Scan tool will show 'no response' to PCM (engine computer). This is why the fuel gauge and volt gauge are inoperative. The PCM is not functioning, so the fuel and voltage data is not bussed to the instrument cluster. When the the CKP sensor shorts internally, the PCM will not function. The connector is located on the right side of the engine, near the rear of the engine block. The CKP sensor is located on the left side all the way in the back. Usually it must be replaced from under the vehicle. This is a fairly common problem.
We replaced that, and still did not fix it. But thank you for that information, both my husband and I learned something new today.
 

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Disconnect the Neg (-) battery terminal and then disconnect the PCM's connectors and look for corrosion or bent pins and check that the PCM's ground connection is legit.
Don't just look at that PCM ground connection and think its ok but remove it and clean the connection with sandpaper and then wipe off any sand paper grit with rubbing alcohol then re-connect.
99% its definitely an electrical issue.
 

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03 WJ, 4.Slow, 3" IRO
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I'm sorry it didn't help.

Moparado has some good advice. Also check to see if any of the pins or connectors have pushed out of their holders.

A vehicle I once owned was notorious for electrical gremlins. A service bulletin was issued to remove the PCM and CPU, scrape the paint and possible corrosion from all contact area then reinstall. That vehicle now has an outstanding reputation for electrical soundness. This may not solve your issue but it is a very inexpensive piece of mind.
 
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