Most common occurrence is the wiring has rubbed up against something and now instead of sending the firing voltage to your injector, it shorts out to the chassis. It could also be that your wiring has come loose, but that is a less likely scenario since it is only occurring on one injector. Keep looking because the chafed wiring is sometimes difficult to find. Follow your FICM connections all the way to #7 injector.:thumb:
Bear in mind there are different kinds/degrees of shorts.
The most familiar is the massive short that blows the fuze. You can have a small short,say just a few or 1 strand of wire touching ground or another wire. This situation will not cause the fuze to blow but will allow part of the voltage to be drawn away from the normal circuit path.
Now every sensor has a wire that carries a reference voltage, the computer knows which reference voltage is for each sensor. For example the reference voltage is 5v but part is being bled off to ground and only 3v is getting there, the computer reads this and throws a code relateing to voltage being low or out of range or some such.
I think i have an open circuit not a short. REading a FICM guide and it says a short would produce a message that says "injector circuit HIGH" while and open circuit would say "injector circuit LOW"
Progress sucks!!!! Thought i found and fixed a loose connection where the wires meet the ficm. STarted truck and check engine light was off. So we used the truck to tow a trailer out to the desert this weekend....engine light came back on....truck overheats...hear that whistle that im hoping is the degas cap im reading about.
About to search but anyone have advice to expose the injectors and check for loose wires? Being told they are under the valve cover. I wrecked my dirt bike and effed my back up. Gonna try to wrench on the diesel today so any advice to make it easy will sure be appreciated thanks guys!!!
Took valve cover and oil rail off. Did not find any loose wires on the #7 injector. Now truck wont start. When cranking over it shows no oil pressure..then after 3 seconds its shows pressure.
Do i need to bleed or prime the oil rail? Any ideas why that sucker wont start for me?
i keep having to crank engine for 20 seconds till it builds oil pressure and starts. done it 3 times now...do i need to drive for awhile to keep that from happening?
The cap and oring appear fine. Hope i installed the oil rail properly. Was super careful lining it up.
Hope oil is making it to injectors. Its almost like the rail is plugged at the intake
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Ford Powerstroke Diesel Forum
5.4M posts
265.8K members
Since 2005
A forum community dedicated to Ford F-series owners and enthusiasts with a Power Stroke diesel engine. Come join the discussion about performance, bulletproofing, modifications, classifieds, troubleshooting, maintenance, and more!