Truck won't start
#1
Truck won't start
So my sister recently had her transmission replaced in her 1996 Ram 1500, everything is hooked up as it was prior to the new transmission theres just one problem.. It WILL NOT start. It turns over but will not start and run. There appears to be no spark BUT nearly every common item to replace has already been replaced. This included (But not limited to) the starter, the coil, distributor, crank sensor, fuses, and it even has a new battery. We thought it might be the PCM so we ordered a new one, and once it was hooked up it still wouldn't start. HOWEVER with the new PCM, the fuel pump only ran for 2-3 seconds. The old PCM would run the fuel pump continuously when the key was in the run/on position. Other than that there were no noticeable differences. Does anyone have any idea of what could be causing the engine to not start now that there's a new transmission?!
Any help is good help
EDIT/UPDATE: After help from you guys here, we got it running and found that the transmission was stuck in first gear (Repair mistake lol). So we got the transmission fixed (As far as we know) but when we went to go drive it again, it ran for a couple of seconds (over 30), and then it died, and we havent been able to start it since. We assumed it was a fuel problem, so my dad replaced the fuel pump; still wouldn't start. So then he went out and got ANOTHER new PCM, and it is doing exactly what it did before, keeping the fuel pump running constantly when the key is in the on position. Not sure what could be at fault this time... Any suggestions/ideas?
Any help is good help
EDIT/UPDATE: After help from you guys here, we got it running and found that the transmission was stuck in first gear (Repair mistake lol). So we got the transmission fixed (As far as we know) but when we went to go drive it again, it ran for a couple of seconds (over 30), and then it died, and we havent been able to start it since. We assumed it was a fuel problem, so my dad replaced the fuel pump; still wouldn't start. So then he went out and got ANOTHER new PCM, and it is doing exactly what it did before, keeping the fuel pump running constantly when the key is in the on position. Not sure what could be at fault this time... Any suggestions/ideas?
Last edited by Maximillio; 03-20-2016 at 04:34 PM.
#4
I tried that earlier and no dice.
No, My dad has been a manager at O'reillys for YEARS, and he's very particular about the parts and companies he buys from.
No, My dad has been a manager at O'reillys for YEARS, and he's very particular about the parts and companies he buys from.
#7
Check for pinched wires between the engine and trans.
Fuel pump should run for about 3 seconds when you first turn the key on, then stop. PCM won't energize it again until you cycle the ignition off, or, it sees the engine turning. (crank sensor) If the fuel pump doesn't kick back on when you crank the engine, then the PCM isn't seeing crank sensor signal.
Fuel pump should run for about 3 seconds when you first turn the key on, then stop. PCM won't energize it again until you cycle the ignition off, or, it sees the engine turning. (crank sensor) If the fuel pump doesn't kick back on when you crank the engine, then the PCM isn't seeing crank sensor signal.
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#8
Check for pinched wires between the engine and trans.
Fuel pump should run for about 3 seconds when you first turn the key on, then stop. PCM won't energize it again until you cycle the ignition off, or, it sees the engine turning. (crank sensor) If the fuel pump doesn't kick back on when you crank the engine, then the PCM isn't seeing crank sensor signal.
Fuel pump should run for about 3 seconds when you first turn the key on, then stop. PCM won't energize it again until you cycle the ignition off, or, it sees the engine turning. (crank sensor) If the fuel pump doesn't kick back on when you crank the engine, then the PCM isn't seeing crank sensor signal.
#9
PCM controls the fuel pump relay. It will energize it for a 'prime', when you first turn the ignition on, but, if the PCM doesn't see the engine turning, it will turn it off. (safety feature) It also cuts power to various other system. (chiefly, the coil, and injectors.) If the fuel pump continues to run, there is indeed a fault somewhere... either the relay itself, or the PCM.
I know you replace the PCM, but, just because it is 'new', does NOT imply that it WORKS.
Grab a friend, and a multimeter, or test light. Park said friend in drivers seat, have him/her crank the engine, while you explore for power. Test the coil feed, and a couple injectors. See if you have power there while the engine is cranking. (I am going to guess "no".)
I know you replace the PCM, but, just because it is 'new', does NOT imply that it WORKS.
Grab a friend, and a multimeter, or test light. Park said friend in drivers seat, have him/her crank the engine, while you explore for power. Test the coil feed, and a couple injectors. See if you have power there while the engine is cranking. (I am going to guess "no".)
#10
PCM controls the fuel pump relay. It will energize it for a 'prime', when you first turn the ignition on, but, if the PCM doesn't see the engine turning, it will turn it off. (safety feature) It also cuts power to various other system. (chiefly, the coil, and injectors.) If the fuel pump continues to run, there is indeed a fault somewhere... either the relay itself, or the PCM.
I know you replace the PCM, but, just because it is 'new', does NOT imply that it WORKS.
Grab a friend, and a multimeter, or test light. Park said friend in drivers seat, have him/her crank the engine, while you explore for power. Test the coil feed, and a couple injectors. See if you have power there while the engine is cranking. (I am going to guess "no".)
I know you replace the PCM, but, just because it is 'new', does NOT imply that it WORKS.
Grab a friend, and a multimeter, or test light. Park said friend in drivers seat, have him/her crank the engine, while you explore for power. Test the coil feed, and a couple injectors. See if you have power there while the engine is cranking. (I am going to guess "no".)
As for the multimeter test, my dads done a number of them, showing no power to the coil when its cranked.. And he did notice that when doing some tests when the key was turned into the on position, it would read 12Vs in some areas like it is supposed to, but only for a very short time, after that it would jump back down to 0.