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Suburban Problem

I have a 2001 Suburban, 2500 with 8.2 litre engine. While driving the engine will quit, power steering will go out, all electrical goes out. It is not heat related or load. I pull over and it will start again immediatly and run fine. For the last few years it has occurred rarely. It has occurred 3 times this week. I have had it to 3 dealers, I have called GM, i have had it to an excellent private mechanic,and no one can solve it. It is a dangerous problem. Any ideas would be appreciated. Thanks

Are you sure that all electrical power goes out? This is a major clue. RSVP

We are always in a panic so are not completely certain, but believe the auxiliary power stays on. One excellent mechanic speculates it may be the camshaft sensor. Before I just start replacing parts,any ideas would be greatly appreciated. Thanks.

It sounds like you’ve got a dead short somewhere that’s cutting the power. Evidently it’s not yet solid enough to blow a fuse, but it will likely soon be. Stuff like that is hard to find. Had that happen on a 7.3 F250 once. Fuel bowl heater shorted out and it shut down one night on the way home, left it on the side of the road, came back in the morning and it fired right up. A week later it shut down on the interstate at 80 mph and wouldn’t start back. Found a blown main fuse that controlled the circuit that fired the injectors. We kept putting bigger and bigger fuses in it till the short smoked and we found out where the smoke was coming from. Heck of a mess, the dang heater element was melted in the filter bowl and required chizzling out.

Skipper

If you are losing all electrical power, there is a momentarily problem in what is called (electrical) power distribution. When the engine is running, electrical power is coming from two sources: the battery and the alternator. Complete loss of power would be a loss from both power sources. The loss could be from a momentary short (in a section unprotected by a fuse), or an open even in wires protected by fuses.
A repair shop which specializes in automotive electrical repairs has troubleshooting techniques which many mechanics may not know.

The battery can get shorts, or opens, in it. To eliminate this possibility, replace the battery. Poor connections, from rust or corrosion, are suspects any place where a wire connects----be it a wire going to ground, or a wire carrying power to components. Every such connection in the power distribution circuits, starting with the battery, needs to be tested, disconnected, cleaned (files, sandpaper), reconnected, and retested. It would be best to REPLACE the cables which attach to the battery.

Just a wild guess, something to check…check your fusible link. I’ve seen one melted where the connection was intermittant.

I’m a previous owner of a 2003 Suburban that suffered the identical problem. Several mechanics were unable to diagnose the issue and our once reliable SUV sat in the garage collecting dust. In the end, a detailed internet search provided the much needed solution. The problem is a single ground wire that runs between the back of the engine and the horizontal wire loom on the top of the firewall (engine side). The wire frayed at the engine causing a break in the circuit. With the engine running I wiggled the wire and it easily disconnected from the engine. Once disconnected the engine came to an immediate stop. I connected the wire to the ground strap located on the driver’s side of the firewall and never experienced the problem again.

9 years later . . .

The OP might not even have the vehicle anymore

True, but it’s very helpful to have a solution so when someone does a search they find it.

We do NOT know what fixed the OP’s problem from 9 years ago

Because they never bothered to return, to tell us what the solution was