early 99 7.3 dies intermittently...
 

I have a problem....lol... I bought a early 99 F250 7.3 6 speed a little over a month ago at auction (had a blown throwout bearing) anyway installed a new LUK clutch and flywheel and it runs like a champ, truck has 389,000 on it, it had a TS 6 position chip installed and I have not a clue as to what any of the settings are. my problem is sometimes driving the truck would cut out and all the lights would come on the dash and die (have to cycle the key off then back on to restart) and then again sometimes it would cut out for a split second and keep on keepin' on. I figure CPS is taking a crap so I go to Ford and get a new CPS install it and the next day it does the same thing! Then I noticed sometimes when I would go to start the truck the "wait to start" light would not illuminate and it would not start but if I would cycle the key off and on and it would come back on. I figured maybe the ignition switch was the problem so I ordered a new Motorcraft switch ($34.00) installed it and the day after it did it once again..:argh: anyway I did a little looking on other sites and some guys said it might be the TS chip causing the problem as when the "wait to start" light does not come on the PCM is not getting power. It did have the cigarette/OBD fuse blown since I got the truck and I replaced it but it did not have any effect on the problem. I have driven it for a week since I replaced the fuse and it has died a couple times (some days it won't do it) but I have no codes stored in the PCM. Also when I switch the TS switch sometimes the truck will die if I switch it while it's running... Anyone had a similar experience?

are you switching the chip while applying throttle?

No, I am at idle when I switch the chip, sometimes it will be ok but sometimes right after I take back off it will die/cutout or just switching the chip at idle will make it cutout and throw all the lights on the dash on and off for a second, That's the only thing I can figure that is killing the truck randomly and turning the WTS light off every once in awhile is the chip, I had read on another forum a guy was having problems similar to mine and it wound up being his chip, I will probably just pull the PCM and remove the chip and look at the connections maybe drive it for a week with it off and see if it happens again, cause I really don't want it to fry the PCM...

yeah i hate electrical issue's there so hard to track down....try this, try that, try this....oh hey it worked :argh::dang:

did you find the problem and fix it ? I have the same chip and had the same problem ended up being fuse 30 under the dash wasn't getting a good contact so I bent the two pronges and re in stalled and no problem sense. fuse wasn't blown pronges had blue color from arcing but was still good. my WTS light wouldn't come on and it would crank but not fire . hope this helps.

Unplug the TS and see how it runs. Its easy the thing just plugs into the back of the PCM just to the left of the break pedal.

Then report back.

Sorry I never reported back but after I pulled the TS chip out the truck ran perfect has never died once one me!

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I would like to run it but it looked like to me whoever installed it rubbed too much of the tinning off of the circuit board...

My TS chip died on me once. I sent it back to them and they fixed it for free.I didnt have a bill of sale or anyting, I was impressed. Only had to pay shipping.

Good to know 01Platinum7.3 but I don't think it's the chip, I think it's the connection, looks like whatever dumbass did the TS install they rubbed the tinning off of couple circuit traces and I believe that is the problem, I bought a silver "Circuit writer" pen that allows circuit traces to be redone without actual soldering, when it gets warmer I am going to pull the PCM again and try to fix the circuit traces this way then re-install the TS chip and see what happens.

Yeah there are clear warnings on the instructions not to rub too much of that off...