Big'un

The ECU is under the hood behind the battery on the firewall

bvboone

were you able to figure out what was wrong with your f150. I have an 03 4x4 lariat with the 5.4 that does the same thing. However, it may let me start it right away or it my take 30 min to an hour befor it will restart. When driving down the road it will downshift in the transmission and all my gauges begin to become quite erratic. It may do this several times and may clear up or shut it self down. I would be interested in what you have learned.

pickupsrule

Do a fuel pressure test.
Sounds like the fuel pump is messed up to me.

RobertC

I have a 01 exp eb and the first time it did wat your truck is doing was after a automatic car wash, lasted two weeks was told needed tune up, wrong, next time was heavy rain, seems water comes up under the fender liner and hits the right bank last plug/coil and messes with the connection i fiddle with it and plug and unplug wires and it works, stranger things have happened, good luck

KenGross

One thing to look for, when you are having problems, does your alarm LED light come or blink like it does when you arm your truck? If so, it could be part of your problem.

westtnfx4

You have either a clogged/bad injector or the coil you replaced it bad. I have bought a new one and it failed right away. Have you swapped the coilsaround to make sure?

yngbld3

What about the MAF ? I had a similar problem & it was the( Mass Air flow ) Maf , which in turn melted my cats & o2 sensors ...which also cracked my radiator fins on my 02 zr2 (chebie lol ) Hope this helps

westtnfx4

^^^yeah that to.

KenGross

You can reset the ECU and the check engine light by borrowing (free) a scan tool from Advance Auto, O'Rieleys Auto, Checker, Autozone, etc. They will tell you how to plug it in to your truck, scan, then reset the ECU. This will wipe out your trouble codes so bring a pen and paper to write down the codes before resetting. This will not fix your problem. You normally do this step after you have repaired the problem. If you are going to replace your ECU, I just did that on my truck for a different reason. It is about a 10 min job. 1st disconnect your negative battery terminal. Then remove the plastic retaining clip holding your ECU. This is located on the passenger side in the cab, against the firewall, close to where your feet would be when riding, just higher. The ECU is an alluminum box about 1/2 the size of a toaster. Then go into the engine compartment and on the opposite side of the ECU, there is a big wiring harness with a bolt in the middle of it. Completly loosen this bolt (10mm?) Your ECU will now come out in the passenger compartment. A great place to get a cheap replacement is www.car-part.com It will list salvage yards. I got mine for $30.00 and shipping was just $10.00 There is a tag on your ECU with the exact replacement needed. Mine was f75f-12a650-arc. You need to get an exact replacement. Good luck!

FX4_Envy

I agree. I'd just about bet he'll be throwing his money away buying an ECU.