OPS/fuel pump FUSE keeps popping

[leo5150]

I just replaced my OPS, fuel pump, relay and added a Leroy Diesel Fuel pump relay To my 96 Suburban and my 20A fuse keeps blowing any low speeds under load 90% of the time. I went 3miles up a winding mountain at a speed of 25 to 35 mph and blew that fuse 23 times! Good thing I had a bunch of fuses going up to 30A!!! Also this morning I blew the fuse putting it in reverse and idling backwards, wen I replaced it I used the peddle a bit AKA 1500-2000 RPM and she went fine. Think there is another issue...... thinking it could be Transmition or what ever that fuse goes to..... just a SWAG...... this is driving me nuts!!!!!!! Anyone have any help that could be thrown my way along with some luck:D

Oh when the fuse pops oil pressure is in the 30 to 50 PSI range and i was driving from FL to WV and the only time they popped is when I was pulling of the highway to get fuel and when I was going up the mountain going around curves at around 15-35 MPH

[DmaxMaverick]

Load-related electrical issues are most commonly caused, at least in part, by failed/failing engine and/or tranny mounts. Look for a damaged or strained harness between the powertrain and frame/chassis, any location that's moving (more than it should) when it shouldn't, and/or loose or poor connections.

Increasing the fuse capacity will only relocate the point of failure. Fuses are cheap and easy to remedy. Components and harnesses, not so much. It's often helpful to downsize the fuse, making it easier to duplicate the problem under specific conditions. Have lots of fuses of the correct capacity handy.

[leo5150]

Can anyone tell me where that fuse goes to and comes from in the vehicle

[JohnC]

I just replaced my OPS, fuel pump, relay and added a Leroy Diesel Fuel pump relay...

Was the fuse blowing before you did all this? If not, you know where to look...

[leo5150]

The fuse was blown and I did not realize it when I sent it to the shop as explained in my earlier post. The mechanic changed the OPS (for a pretty penny to) that is located under the intake behind the fuel filter housing unlike my 86 K5 6.2l. He had told me about the fuse and that it was blown, then he said that if it keeps blowing I should get the Leroy Diesel relay and that should fix it. So I did..... along with the fuel pump (ACDelco) because I could. Well the damm fuse still pops....... I also just changed the fuel filter because the old one looked brown..... so you are saying that the fuse loops back to the OPS and fuel pump??? I checked the fuel pump by unplugging the relay while running and the engine kept working so the fuel pump is good....... what other tests can you suggest

[leo5150]

Well the fuse just popped again and every fuse I put in is popping it’s the keys out. Now I need to figure out where to check to see where the problem is.

[JohnC]

Fuses blow because the circuits they protect are drawing too much current. So, either that fuse is feeding a faulty component or you have a wire that intermittently shorts to ground.

Installing a larger fuse only makes it more likely you'll have an electrical fire.

First place I'd look is the wiring running back to the fuel pump. Second, any wiring associated with that circuit that jumps from the engine to the body or frame.

[N9Phil]

See if this will help.


https://www.thedieselpageforums.com/tdpforum/attachment.php?attachmentid=4236&stc=1&d=1553513432

[leo5150]

Sorry it is taken me so long to post the reply to this, but it turns out the wiring harness was rubbing against the steering wheel shaft…… I really needed my glasses for this and sometimes it’s best to look for the easiest fix possible…… :(:p

[DmaxMaverick]

Thanks for the update.

Easy is good. We like easy.