Not starting when engine has heated up

2004 PONTIAC BONNEVILLE
153,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC
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MEMBER2018
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When I get up to start the day the car starts and runs fine, however as the day goes on and the car heats up and if I turn it off it will not start again. I have to let it sit and it will not start again until the next morning. Since this started I have replaced the camshaft, crankshaft, MAP, airflow, sensors, the top oxygen sensor that is at the top of the motor. I have replaced the spark plugs and wires, fuel pump and fuel filter, fuel regulator. I have replaced the thermostat three times. Yesterday morning the car started and was running fine and then it backfired. I restarted and drove it the rest of the day. This morning it started and it backfired and will not restart.
Jul 19, 2018 at 10:12 PM
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PATENTED_REPAIR_PRO
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I suspect possibly a relay causing this. Start with replacing the fuel pump relay and see if the problem goes away. It is located in the rear fuse block. This is located under the left rear seat.
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Jul 20, 2018 at 9:09 AM
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MEMBER2018
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I replaced the fuel relay and that did not make a difference. I replaced the battery while the engine was still cold and when I tried to start it the motor jerked real bad so I turned the key to the off position and then back on and it started. However, once it got warmed up it would not start. So this morning I took the air hose and blew out all the area where the fuses are and around the top of the fuel pump and put the jumper cables on it and it started but still will not restart after it warms up. I noticed there is a black box located right behind the back passenger's side tire that has two hoses running from it and it is making a rumbling noise when the car is in park, will stop when I turn off the AC but will start again a few minutes later. When the gas tank is completely full it will not make that noise but when the tank gets down to or below a half a tank of gas it will start rumbling again. so I disconnected the hoses and tried to clean it off but when I reached up there and grabbed the hose it is like hot rubbery and was all over my hand. Anyway original problem still an issue.
Jul 27, 2018 at 9:23 AM
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PATENTED_REPAIR_PRO
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That is the ECAP canister.
Grab a can of starting fluid and then next time it will not start when warm, spray two to three small shots of starting fluid into the throttle opening then quickly make it to the key and try, then let me know if the engine will start for at least a few seconds or not still.
Be careful not to spray any of the exhaust manifold.
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Jul 27, 2018 at 12:12 PM
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MEMBER2018
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No, it still will not start when hot with the starter fluid. I have removed the ECAP canister and cleaned it out. All that did was make the noise stop.
Jul 31, 2018 at 10:31 AM
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MEMBER2018
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Is there any chance that the ignition module would cause this?
Jul 31, 2018 at 9:04 PM
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PATENTED_REPAIR_PRO
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That should have said EVAP.
It could be an ignition control module since it appears you have no spark since it will not even start with the starting fluid.
Aug 1, 2018 at 9:41 AM
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MEMBER2018
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Is there a way to test the ignition module?
Aug 1, 2018 at 9:58 AM
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PATENTED_REPAIR_PRO
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Autoparts stores used to have ignition module testers way back, call them up and ask if they still have them testers and if so remove it and take it I to be tested.
Aug 1, 2018 at 4:31 PM
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MEMBER2018
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Okay, do you have any other thoughts on what else could be causing this issue in the meantime?
Aug 5, 2018 at 4:16 AM
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PATENTED_REPAIR_PRO
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Not at this time. Is there any check engine light that flashes or stays on when this happens and if so unless I already asked, any trouble codes?
Aug 5, 2018 at 8:48 AM