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Discussion Starter #1
I have a 1999 F350 7.3L powerstroke 285K miles. I havent had it long (couple months) but want to learn how to DIY as most people do on PSN. It has been hard to start ever since I had it (winter time). Had it plugged in for about an hour and went to crank it and it turned over normal for about 5 seconds and then suddenly slowed down cranking like a battery dropped out or something. I cleaned the terminals and charged batteries. After this the batteries had much better connection and cranked fast but I noticed no wait to start light. I have checked all the fuses and all are good.I put a new GPR on but no change. Any ideas?
 

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Double check fuse #30 under the dash. That controls the fuel bowl heater and the PCM. The fuel bowl heater shorts out blowing the fuse. You can unplug the heater, change the fuse and you should be good to go. The primary indicator is the lack of a wait to start light. Thats usually the first clue.
 

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Yeah I have pulled that fuse about 3 times and looked at it. It looks good, I put a meter on it yesterday and checked it; ohms out as good. I think I will just replace it anyway and maybe check the voltage at the fuse box on that fuse since everyone points to it as a culprit.
 

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Try connecting to the PCM via the OBDII port with a scan tool. If it is unable to connect, you may have a problem with the PCM. The first clue for this is no WTS light with fuse #30 still in good working order.

BTW, do you have a chip installed on the PCM?
 

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Discussion Starter #5
Thanks for the input. No I am not aware of any chip on the PCM but I have only had the truck for a couple months. I don't have a scan tool either. Sounds like I need to invest in some electronic tools to troubleshoot the 7.3L. I did check the voltage on fuse 30 and with the ignition on, the voltage is 12.5 volts on each side so all is good with power to the fuse. I will have to find someone with a scan tool; don't want to have to tow to a repair shop but not sure what options I have at this point.
 

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Where do you live?
 

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Just an FYI too, plugging the block heater up for an hour won't do much good. You need atleast 2-3 hours in my opinion.

Also, if you have an android phone, you can get the torque app for $5 to be used alongside a $15 Bluetooth scanner. It won't read stored codes, but will read check engine lights along with multiple PIDs for the truck.
 

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Discussion Starter #9
OK it has been a while since I have been on the forum about my '99 F350. I found a mechanic acquaintance at work who is a good diesel mechanic. He came to the house and put my truck on a scan tool and it would not read anything, system not responding. We checked the fuses and typical wiring harnesses for loose connections and found none, put a spare battery he had in his truck in it with no luck. I pushed on the wiring harness end of the PCM and he pushed on the PCM case from the inside. Then I heard him tap it a couple times pretty hard. He called it the "slap test" (this is a new one for me). After the slap test, the 7.3L came back to life, everything worked like it supposed to and she cranked right up!
Now my question is how long do I have before I will have to buy a new PCM? Any words of advice?
 
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