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How does somebody that only drives my Screw, do a PATS test?
PATS is Passive Anti-Theft System. If you search the forums you will find a lot of info on it. Basically it has been triggered if the Theft light is blinking. Sometimes you will get a false positive if you have some other device on your keychain that has a chip in it (your key has a chip in it to tell the truck it is a match). For example, there are some key fobs for office buildings, or key fobs for gas stations that I have read can cause interference.
Thanks for all the input here. 03 Screw 5.4 4x4 170k. My issue was it would crank and start when cold (i.e. overnite) but when warm after 5 minutes of driving it would crank but no start.
Got $12 relay to change FP Relay. No workie
put old FP Relay back, replaced PCM Relay. Workie
I did notice the THEFT blinking light problem when crank but no start. Checked the PATS code by turning the key on for a minute or so and the result, by reading the THEFT blinks, was 1 followed by 6.
I have a 1998 F150 and I have the same problem where it's fine on cold starts but after driving a few minutes it'll crank, sort of fire, then stop. Changed the fuel filter since that'd be easy but no luck. Ford dealership said it was the fuel pump relay but said the bad relay caused damage to the fuel pump. Does that make sense? I didn't know a bad relay could damage the fuel filter. I'd rather just change the relay my self instead of paying them $900 to change the relay and the pump.
Well, why don't you just spend the $20 for a relay and try it? It's real easy to get to and takes about a minute to change. Parts stores have them, it's a standard item.
I have a 2003 F150 5.4L. About once every couple weeks, and I don't know why, my truck won't start. It turns over and is trying, but it won't fire up. If I go back a few hours later, sometimes it starts. Also, if I jump start it, it usually starts (sometimes it doesn't though)
I pulled off the fuse cover and noticed that relay #2 (the one for the PCM) was really hot. I could touch it, but it is very hot. It is also yellow and all the other relays are black. That makes me think it has been replaced before. Does that usually get hot when starting the truck?
Do those symptoms match what would happen if that relay was bad?
Thanks for your help!
Just had this issue with my 2002 F250 4WD 5.4 V8. All my fuses and relays were good. Went to pull cam sensor, and water temp sensor... checked coils for voltage, found none with the key on. should show 12V at coil. Final analysis, in MY case, it turned out to be a three volt voltage drop at the positive battery terminal. I aborted the stock terminal, which was comprised of this terminal block with three red cables coming from it. one from alternator, one to starter, one to ....wherever. I replaced that with a honkin' aftermarket battery terminal, cleaning both pos and neg terminals on the battery. Truck fired right up. I'll post pics if I can figure out how....
Just had this issue with my 2002 F250 4WD 5.4 V8. All my fuses and relays were good. Went to pull cam sensor, and water temp sensor... checked coils for voltage, found none with the key on. should show 12V at coil. Final analysis, in MY case, it turned out to be a three volt voltage drop at the positive battery terminal. I aborted the stock terminal, which was comprised of this terminal block with three red cables coming from it. one from alternator, one to starter, one to ....wherever. I replaced that with a honkin' aftermarket battery terminal, cleaning both pos and neg terminals on the battery. Truck fired right up. I'll post pics if I can figure out how....
Sorry I have disappeared for a few days. I've been working stupid, long hours, so I've just been riding my motorcycle to work until I get some time to work on this. I spent a few hours yesterday going through more of your ideas.
First I put a new fuel filter in. Probably not the problem, but it was time anyways.
Then I went through your list, SSCULLY
- PATS is working. I have tested it using several different methods I found on the forum. The theft light does not flash.
- I checked the battery cables and cleaned the terminals to be sure.
- For the fuses, I did the pull and stare method. I thought I would try the relay first, then go through with a meter.
- I have not yet jumpered the fuel pump relay. I was going to do that next, but the battery died, so I connected it to my wife's car to put a little charge in the battery and the truck fired right up.
So the good news is, it started. The bad news is, I'm not sure I did anything. Sometimes it just fixes itself and then dies again in a couple weeks. Time will tell.
So I think I'm on hold until it doesn't start again. It's hard to tell what to fix while it's working.
You guys have been awesome. Thanks so much for your help. I may be back if it stops working again (hopefully not).
Every couple weeks my truck will turn over but not start then remove key replace and it starts. I noticed the other night when it did this that Theft was flashing pretty fast.
PATS is Passive Anti-Theft System. If you search the forums you will find a lot of info on it. Basically it has been triggered if the Theft light is blinking. Sometimes you will get a false positive if you have some other device on your keychain that has a chip in it (your key has a chip in it to tell the truck it is a match). For example, there are some key fobs for office buildings, or key fobs for gas stations that I have read can cause interference.
Every couple weeks my truck will turn over but not start then remove key replace and it starts. I noticed the other night when it did this that Theft was flashing pretty fast.
Can you complete your profile or post your the information on your truck ?
11-27-2012, 02:54 AM
