truck wont start if its cold outside
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Joined: Jul 2010
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From: PA
I have a 95 5.9 l v8 2500 and i aslo need to turn the key to the on poition and let it sit for like 5 min then go out and it fires right up as well.
It sounds like we're having similar issues. My truck (95 2500 V10) will also not start when it's cold outside, but if I turn the ignition to the ON position and leave it there, something seems to warm up and I can eventually start the truck. The colder it is, the longer it takes.
In my case, when it's really cold I also have no spark and no fuel. Neither the ASD relay nor the fuel pump relay get activated by the PCM. I confirmed this by testing voltage across ports 85 and 86 for each relay plug in the PDC. When the truck is working properly, I get 12 volts, but when it's not working, there's no voltage, indicating that the PCM is not closing the ground like it's supposed to.
When it's cold outside and the truck won't start, I go turn the ignition to ON and wait. Eventually I hear the ASD and fuel pump relays start clicking rapidly. This goes on for a couple minutes and then they stop clicking and stay on for a couple seconds. At which point I hear the fuel pump run for a couple seconds and I know that I can crank the truck and it'll start right up. After all of this, it tends to run a little rough and I have to keep on the gas for around 30 seconds, then it it will idle fine and I can drive the truck for the rest of the day without a single problem.
At this point, I think I need to check the Crankshaft Position Sensor and wiring. According to my repair manual, the PCM reads the CKP sensor values before activating the ASD and fuel pump relays.
Let me know if the heat lamp on your PCM makes any difference.
-haZZard
In my case, when it's really cold I also have no spark and no fuel. Neither the ASD relay nor the fuel pump relay get activated by the PCM. I confirmed this by testing voltage across ports 85 and 86 for each relay plug in the PDC. When the truck is working properly, I get 12 volts, but when it's not working, there's no voltage, indicating that the PCM is not closing the ground like it's supposed to.
When it's cold outside and the truck won't start, I go turn the ignition to ON and wait. Eventually I hear the ASD and fuel pump relays start clicking rapidly. This goes on for a couple minutes and then they stop clicking and stay on for a couple seconds. At which point I hear the fuel pump run for a couple seconds and I know that I can crank the truck and it'll start right up. After all of this, it tends to run a little rough and I have to keep on the gas for around 30 seconds, then it it will idle fine and I can drive the truck for the rest of the day without a single problem.
At this point, I think I need to check the Crankshaft Position Sensor and wiring. According to my repair manual, the PCM reads the CKP sensor values before activating the ASD and fuel pump relays.
Let me know if the heat lamp on your PCM makes any difference.
-haZZard
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How would this prevent the PCM from turning on the fuel pump and ASD only when it's cold outside? Once the truck starts up it runs strong without any problems.
-haZZard
-haZZard
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From: NH
Sorry, I was replying to alanpvw post, where he says if he turns the key on and off ten time's it will start.
And maybe you should start your own thread instead of jacking his and complicating matters.
And maybe you should start your own thread instead of jacking his and complicating matters.
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I didn't mean to be rude. Nor was my intent to hijack this thread, but based on what the OP has said so far, I believe we have the exact same problem.
I have started my own thread by the way (https://dodgeforum.com/forum/2nd-gen...-problems.html), but I believe that if more of us with the same issue can share our troubleshooting results in the same thread, we're more likely to find a solution. And this seems to be the most active thread on the topic at the time.
-haZZard
I have started my own thread by the way (https://dodgeforum.com/forum/2nd-gen...-problems.html), but I believe that if more of us with the same issue can share our troubleshooting results in the same thread, we're more likely to find a solution. And this seems to be the most active thread on the topic at the time.
-haZZard
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From: NH
No problem bud, it was my bad for not quoting his post. However, I now think both of you should check the pressure anyway, it may run fine once started, and the pressure may be in spec, but it's what it does after the motor is turned off. The regulator is also the fuel filter, so you never know what kind of strange things can happen when it gets cold.
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cant we all just get along here.. lol...the truck is running good right now. temps have only been down to 50 degrees in the am.
i will keep posting problems/results/and so on . soon as the cold comes back it will be hell again im sure
i will keep posting problems/results/and so on . soon as the cold comes back it will be hell again im sure
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yes hazzard. i beleive we are having the exact same problem here. thank you for your input. ill post about keeping the pcm warm as soom as the weather drops for a low of 35 degrees or lower. it seems that 33 degrees and below causes failure. im almost tempted to buy a pcm and try it, but after throwing away money on a fuel pump, crankshaft sensor, camshaft sensor and relays im a bit hesitant.
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problem solved...i think.. sorry for the late reply but the weather seemed to be in the 50`s for a week.. well now it is in the 20`s.. i took the pcm inside the house now two nights in a row and kept it near 75 degrees. both mornings installed it in the truck when it was 24 or so degrees. boom. truck started right up. ran great. weird. so finally got to the bottom of the problem. the pcm.. thank you guys for reading and posting. (hey you) gave me the idea of removing it and putting it in the freezer.. lol. just instead of putting it in a freezer i removed it from the truck when outside air temps were like a freezer and i kept it inside room tempts. anyway. problem solved. thanks again for all the help