Fuel gauge

Tiny
#1SAINTSFAN
  • MEMBER
  • 2002 SAAB 9-5
  • 2.3L
  • 4 CYL
  • TURBO
  • 2WD
  • MANUAL
  • 176,667 MILES
About 3 months ago my fuel gauge started to go up and down no matter how much gas I had in. So one day it just shut down on me as I was driving. I pulled over and sat here for about 15 minutes and tried to start it and it started but shut right off and wouldn't start again. So I got the car towed got it home and noticed the when I turned the key I could hear the fuel pump power up but no start and my gauge still read empty. So I changed the pump I put it in and the car started after awhile, but I had a code for my coil pack. Changed that still having problems with the gauge. A couple of days ago the car tried to cut out on me but I let off the gas and put it in neutral and it sputtered and then stared running smooth again. I haven't driven it since. I just go and start it with no problem. The gauge went up to half a tank then dropped but kept on idling.
Monday, August 12th, 2019 AT 2:12 AM

11 Replies

Tiny
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  • MECHANIC
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Hi, thank you for using 2CarPros. Lets see what we can do to help you out.

I have a couple questions I need you to answer if you can.

1. Have you checked for any new codes since the coil Replacement?

2. Can you tell me if the motor always wants to die when the gauge is reading empty?

Thank you, Rich
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Monday, August 12th, 2019 AT 7:39 PM
Tiny
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It does not want to stall and I have no engine lights on. It just stalls out of nowhere. It starts to sputter and at like it is going to cut off. This happened three days ago, but I kept on giving it gas and then it seemed to clear as if something was blocking the line. I looked at my old fuel pump yesterday and it seemed to be fine but I changed it thinking it was the problem, but the new has the same issue. The gauge also I almost forgot when I was driving when I had that issue the gauge showed 1/2 a tank then the gauge just dropped.
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Tuesday, August 13th, 2019 AT 5:50 AM
Tiny
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First, Did you change the fuel filter when you did the pump?

At this point some odd things are going on and I can't tell yet if it is one issue or two. When crazy things happen like a fuel gauge bouncing around and the motor trying to shut off, two things that have nothing to do with the other I start thinking the PCM (Power-train Control Module) IE the computer has failed.

Lets make sure it is two issues and not one, though the gas gauge bouncing around could be a bad gauge or the PCM. Does the gauge ever read more gas than you know is in the tank? IE you know you have a half tank but the gauge goes up to 3/4?

At this point I would change the fuel filter if you have not. When you do blow through the inlet side. If it is plugged you will feel resistance varying from a little to you cant blow through it at all. This means it was plugged. If you feel none then it was fine, but we need to know that one way or the other.

I kind of bounced around a bit here so be careful to answer all my questions and we will go from here.

Thanks, Rich
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+1
Tuesday, August 13th, 2019 AT 6:46 PM
Tiny
#1SAINTSFAN
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Thanks and I will change the filter because it has never been changed. Also I will clean the electric plug for the computer to make sure there isn't any corrosion.
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Wednesday, August 14th, 2019 AT 3:42 AM
Tiny
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Great, let me know how it turns out.

Rich
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Wednesday, August 14th, 2019 AT 4:29 PM
Tiny
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Yes.
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Monday, August 19th, 2019 AT 7:47 AM
Tiny
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Does "Yes" mean you fixed it?

Rich.
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Monday, August 19th, 2019 AT 6:03 PM
Tiny
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Nope I didn't. Yesterday I changed the fuel filter but no difference still my gauge is not working. What next?
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Wednesday, August 21st, 2019 AT 2:06 AM
Tiny
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When you changed your fuel pump, did you just buy and replace the pump or did you buy the whole unit with the pump and sending unit?

Rich.
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Wednesday, August 21st, 2019 AT 7:39 PM
Tiny
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I changed the whole unit.
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Thursday, August 22nd, 2019 AT 2:45 AM
Tiny
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Okay, the gauge issue is acting like a bad ground. I don't know if you tested it when you installed, but can you get an ohm meter with sharp probes, locate where the ground wire is screwed to the car, pierce the wire about an inch back from the connector and put the other probe on the connector. You should read 0.004. This will test the connection from wire to connector. Then put 1 probe on the connector and the other to the body away from the screw. This should read 0.004. This will test the connector to the body. Any higher on either test and you have a ground issue.

Let me know what you find.

Rich.
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Thursday, August 22nd, 2019 AT 5:10 PM

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