corey282

After I posted this I went down the street and spoke with a mechanic. He said he had an impala where he had to replace 3 fuse boxes.. The reason being the connector was corroded. It makes sense becuase it a simple cover with no weatherstripping to keep the moisture out. I do have my doubts, but the next step is to find the plug connector at a junk yard and use dialectic grease on all the connection and then wish for the best. I will also replace the fuse box again and not take any chances. I'll report back after several months goes by. I'm guessing at the 3,000 mark was the first time I got a crank, no start, but I want to go at least 5k miles before I feel confident about it.

tech2

that pin looks burned. loose pin fit causes the current to jump and spark burning the connector. definitely replace the connector and make sure the pin fit of the new connector has drag to it when slid off the pin. corrosion causes resistance that lowers current flow.

corey282

The way the box is contructed is like putting a processor in a motherboard. All the pins go in at the same time so it's impossible to judge that. The only thing I can do

it get that connector at a junk yard and visually inspect it.

The 3 connectors are linned up in the box then it's pressed it, and each block is bolted in from the top of the fusebox

tech2

break off a pin from the wrecked panel.

dielectric grease stops corrosion...you have a burned terminal.

shame if you did this a 3rd time.

corey282

Original = zero times
replacement = 1 time

And I'm not a mechanic. In fact, there are not many mechanics that know what this is, and how to fix it. It's an intermittent problem and if you read my OP you will see I had it towed 5 times to my mechanic, and each time he told me there was nothing he could do without a nostart. Being desperate to fix this I had to ask around, pulling my hair out not knowing the problem. You can look around the internet and see there is not any info on this, except for the video I posted, and even he does not know about the bad connectors. The only reason I'm doing this to this amount of detail is to help someone else from throwing potentially thousands of dollars in labor to drop gas tanks to repeatedly replace fuel pumps that are not bad, fuse boxes and multiple tows. Even the dealer is not aware of this, by not selling a replacement connector block or even replacement pin (female) connectors.

tech2

and you did a great job; you found the bad part...but what was the cause of the failed part. if you don't fix that; destiny will be a 3rd ubec. When the same part fails multiple times...i question it.

jjrbus

I have answer for you, you do have my sympathy! Intermittent electrical can drive a person over the edge!

MitchM

so what I learned from all the above posts is 1/ during manufacture, a particular pin can be improperly positioned, and QC may not catch this. 2/ an improper position of a pin may cause a loose connection , which may eventually result in arc ing of that pin and improper current being supplied to some critical part like the fuel pump. 3/ a loose fit for the FP relay pin , or corrosion on the pin from the fusebox cover not being water proof, will cause arc ing of current on that loose or corroded pin , resulting in 4/ a no start of the fuel pump due to insufficient current coming off the f p relay's bad pin , and possibly there will be 5/ burn 'witness marks' around the FP relay because the arc ing generates heat .

so replacing the FP relay may fix the problem , but only temporarily. recommendations are 1/ make sure the cover on fusebox is water tight , 2/ check for corroded pins or burn marks around certain fuses or relays, 3/ you may need to put in a a whole new fuse box, or may be just replace the fuse box relay or connector . or : you can wire in an external relay. sounds like we need to be carrying an extra f/ p relay and connector .

many thanks to all who contributed to this very important diagnostic thread. And a special thanks to OP, whose observations and history were so helpful. (I'd email you a case of your favorite beer if I could. )

grgarry123

Hello,

I'm not mechanical at all but I have a similar issue with my 2011 GMC Savana cranking but not starting we have replaced the fuel pump and fuel relay. Today they had the van torn apart looking at the electrical system but really telling me they weren't sure where the problem was. Can someone explain to me what the final fix ended up being for this problem. I would like to make my shop aware of this information.

Thanks

mountainmanjoe

@grgarry123 there are many things that can cause a no start condition. Not everybody is going to have to have the same problem.
A bad fuel pump or circuit can be quickly ruled out with a pressure gauge, but any decent shop already knows this. Let them diagnose it properly or get a second opinion.