Here's a brain melter for all you chevy guys. I have a 1990 Chevy Suburban 5.7L 4wd that constantly blows the ECM B fuse. First thing I replaced was the fuel pump relay as it only happened when the ECM is connected and the fuel pump relay was connected. Cranks but still no go. Found a burnt wire and replaced the wire that connected to the manifold. Started once let it run in park then turned it off. Started it again a few minutes later and when I shifted into reverse the fuse blew and the engine died completely. Traced all the wires from the ECM to their various places, disconnected the fuel pump power and the fuse still blows. Now it won't start at all just cranks, any ideas?
2007-07-30 15:43:02 · 5 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
since you had a burnt wire on it to start with id start looking for the cause of that first,as long as any wire touches metal anywhere on it,its going to blow fuses,find the cause of the burnt wire,and you,ll find the short in it,good luck on it.
2007-07-30 15:54:50 · answer #1 · answered by dodge man 7 · 1⤊ 0⤋
You obviously have a dead short in the wiring somewhere. I'd start with the battery and then the alternator and then the solenoid and then the multiple wires around the engine area. It's fairly common that the bundle that typically lays on the passenger side of the engine will be suspect. The old wire loom crumbles away and the wires rub against the top of the cylinder head or exhaust manifold and or intake manifold and everything will be 1/2 normal. Intermittant problems pop up or the engine dies for ne reason or you blow a fuse or burn a fused link.
It could even be under or in the dash. A good shop that handles electrical problems only can have an answer for you in an hour.
Good Luck!
2007-07-30 23:05:17 · answer #2 · answered by CactiJoe 7 · 0⤊ 0⤋
When you shifted into reverse you closed a switch to a light circuit. Trace out the wireing. Has it got a trailer hitch?
Look for a short in that wireing. Especially if the wireing goes under a door.
As to the no start now, you may have blown a fuse link in the wireing harness. A really bad short could burn out a switch connected to it.
Perhaps you should get an expert to help you.
2007-07-30 23:00:19 · answer #3 · answered by Wisdom 6 · 0⤊ 0⤋
May sound odd but sometimes it helps to find out what caused the wire that was burnt to burn. Go from there.
2007-07-30 22:49:40 · answer #4 · answered by Takarie K 4 · 0⤊ 0⤋
Could be bad wire to the ECM or the ECM its self. You need further diagnose your problem
2007-07-30 22:48:11 · answer #5 · answered by jim 5 · 0⤊ 0⤋