STILL not starting when hot!!
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Senior User
Joined: Sep 2006
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I had some time just now to go out and work in my truck. I checked the FPR they way you guys said to and that seems ok. But after i warmed it up and took if for a drive i tried to start it back up agian. Didn't start. Tried again, still nothing. So i unplugged the MAF. Started up! Left it on again to keep it warm and plugged in the MAF. Shut it down, left it for about a minute, tried to start it--nothing. Unplugged the MAF again and BOOM---It started. So i let it run for a minute and tried to start it. it started with the MAF unplugged. Does this sound like the MAF is done or just a coincidence?
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Joined: Aug 2003
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From: St. Peter
Unplugging the maf will put the comptuer into failure mode. Its not a guarentee that it is your maf sensor. But it is possible that it is causing a problem.
Check to make sure that nothing is blocking the maf housing.
I had a tauraus that had a no start problem. Would start, run for 1/2 second, then kill. I spent like 3 days on that car trying to figure it out, distributor testing, TFI module testing. All good. Then I unplugged the MAF and bingo! it worked. Put a new MAF on, and no result. Still died. Well, I took the whole housing off, and a bug had actually cralwed into the port where the hot wires sit, and died. Therefore blocking off the airflow to the MAF, or either increasing the air velocity so the maf thought the engine was at like 5k rpm and choked itself out. Either way, cleaned out the dead bug, and all is well. So be sure to removed the whole aluminum housing the MAF sits in, and look at it. Or it might be your MAF sensor. You dont have a K&N air filter do you? or any other sort of oil wetted oil filter?
Check to make sure that nothing is blocking the maf housing.
I had a tauraus that had a no start problem. Would start, run for 1/2 second, then kill. I spent like 3 days on that car trying to figure it out, distributor testing, TFI module testing. All good. Then I unplugged the MAF and bingo! it worked. Put a new MAF on, and no result. Still died. Well, I took the whole housing off, and a bug had actually cralwed into the port where the hot wires sit, and died. Therefore blocking off the airflow to the MAF, or either increasing the air velocity so the maf thought the engine was at like 5k rpm and choked itself out. Either way, cleaned out the dead bug, and all is well. So be sure to removed the whole aluminum housing the MAF sits in, and look at it. Or it might be your MAF sensor. You dont have a K&N air filter do you? or any other sort of oil wetted oil filter?
Cargo Master
Joined: Feb 2002
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From: Tucson USA
as I think about it there was a guy on here a week or so ago again simular problems, turns out he had a bad fuel pump even though it would start and run, but would die after a short while so you may have to head in that direction. I beleive he wrote his pump was good when checked cold also, but lost it after it was run for a while.
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well i stopped by my local parts store (bumper to bumper-they know just about anything and call every repair shop around to help) he recommended the coolant temp sensor. He said that it might be telling the computer that it is cold at every start, sending the wrong fuel/air mixture. The other part was the air temp sensor int he inlet of the intake. So, i replaced the coolant temp sensor and took it out. I let it sit for about 4-5 minutes and tried to start it, it turned and didn't start, tried again and boom!! It started right as i turned the key. So i drove it the rest of the day and it started on the second turn every time with no problem. Now I just have to narrow the rest of it down, i am going to check the fuel pressure next when i get a tester. Thanks, ill keep everyone posted--John
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From: St. Peter
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Moderator
Joined: Jan 2004
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From: SW Va
With you having to try multiple times to start it hot, makes me want to suggest, try swapping the A/C power relay, for the Fuel Pump power relay & see if you get positive results. These relays are known to be heat sensitive.
Keep us posted on your troubleshooting results.
Keep us posted on your troubleshooting results.
Moderator
Joined: Jan 2004
Posts: 13,851
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From: SW Va
Ok, well on my 99, #5 relay, is the fuel pump power relay. So standing by the drivers side fender & looking at the power distribtion box, #5 relay is the 4th one counting the row closest to the fender & moving left, from the firewall.