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Crazy Electrical Issues w/ No Start - NOVEL

3K views 6 replies 2 participants last post by  jpleatherman 
#1 · (Edited)
This might be a novel, but hopefully by the end many of these issues will also relate to others and lead to some successful problem solving. Thanks in advance if you read and offer advice.

It all started in Early Tennessee November 2016 when I bought this 2004 4.2 EXT 4x4 from a family friend mechanic who had just finished an engine swap on it. Roughly 230,000 on the vehicle with a rebuilt Tranny about 40k miles ago and the "new" engine has about 120k on it. Flash Forward.....

1.) After a week of driving, my ABS and Brake lights occasionally come on and ding at me as I back into my parking spot. Gets worse and worse where it's an almost constant ding driving along. So, instead of messing with new sensors I'm just gonna replace the wheel hubs since I'm going to put new Brakes and Rotors on anyways. During this first couple weeks, the RPM Gauge had also decided, while driving, to drop to 0 and slowly climb to 5k or so and just sit there over 30 mins of driving. (Engine feel/sound was okay, knew it wasn't a true RPM reading). Unplugged the battery for 30 mins and it reset itself *known issue of bad gauges on these things*

2.) One of the 1st cool nights and as I'm driving, I start getting some hesitation/stalling coming home. Gas gauge reads just a hair under 1/4 tank so I think maybe it's just lower than what it says or it's sucking crap up off the bottom of the tank. Make it to the Gas Station and fill up. Rough start but it makes it hope, seemingly better. Sets off the Check Engine Light with a Lean Reading on one of the cylinders, I can't remember. Next morning, stalls out of the driveway but makes it to work and the CEL had gone off. Stalls 6-7 times on lunch break coming home so at home I pull the MAP sensor under the impression that may be reading bad. Works another day or so, seemingly better.

3.) Weekend arrives so I'm onto the Brakes/Rotors/Hubs. Finish that and decided to clean the Throttle Body real quick. Cleaned the correct way and put it back on. [Battery unplugged the whole time] Turn the key......NOTHING.:eek: I check the TB and spray some gas in there, it cranks over for about 1 second then nothing.

4.) Convinced the Fuel Pump went bad, given the past few days issues, I get a new pump and cheerfully drain out the 22 gallons of fuel I had JUST put in the couple days before. 5hrs later, new pump in, all plugs connected and I go to start......NOTHING.:mad:

5.) Google-Trailvoy-GM Nation-....I decided to throw some money at it and give her all new parts. [ MAP Sensor - Ignition Switch - CAM Sensor - Swapped fuse boxes from a Pull-a-Part and checked all fuses front and back ].....NOTHING. I start checking grounds to the best of my ability but in the end I have it towed to my local mechanic.

6.) Get a call a couple days later and he said it was the ground to the fuel pump, which I had checked or so I thought. Anyways, I drive off and all is fixed finally. Next morning (been 20 degrees over night) I go to start and it's dead again!!! I can't hear the fuel pump starting. Towed again and he sits on it for a few more days and that weekend with a little TN blizzard (2 inches) I get it back just in time for 4x4 safety. The next morning ( again, 20 degrees or so over night) I go to start and no fuel pump sound, cranks but no start. I head off and get a NEW Battery just because it needed it and who knows...Still nothing. Towed again.

7.) This thing sits at the shop for about a month, starts every day for the mechanic, even on cooler days 35-40 lows during this warm winter. At the end of the month I decide I'll just risk it since it's started for him the whole time. He's run a new ground wire to the Fuel Pump as well as a new Battery Ground harness and checked the grounds up in the engine compartment. So far, it's started every morning for me since then, even that next morning it was 18 overnight and I got up early, 6am, and it started right up for me. I'd wondered about the PCM maybe having moisture and freezing/expanding a connection up on the engine block?? Who knows...During this 2-3 times in the shop, I notice my Fuel Light had come on and it just sat at empty the whole time. Now with it back, I drive it for a week and keep an eye on my Trip Miles till the next fillup.

8.) 1st new tank of gas after the full drain/pump swap and partial fillup. Low and behold, the gas gauge seems like it's working!!! Granted it's just slowly climbing....1/4 tank....1/2 tank...( park for work ) Lunch and it's up to 3/4 and then full. Another week driving, another tank of gas but this filllup it only goes to 3/4 on the gauge, even though I know it's full. Oh well, keep an eye on the trip til I decide to get a new cluster, right?

9.) McD's for breakfast and.......Driver Window/Door buttons don't work! What in the world!! Mirror joystick adjust Driver side but not passenger. *read the forums* Swap the Drivers and Passenger. Driver works on passenger but passenger not on the driver. Module good??? I get the door panel off and start checking wires. I get 12v from the frame plug (4 wires) I also get ground. Plugged in I get 12v to the thin orange wire at the control panel (Which is super clean inside, no sign of moisture or electrical frying). I haven't finished looking into this all the way yet though I figure it's some ground. Key Fab locks/unlocks all 3 other doors right now.

10.) The next day, my daughter rolls down the back driver side window, few clicks at a time. But it won't roll up!! I pull into a parking lot to try and get it and not luck. (truck is on and in park) I go to shift, and the shifter button won't go in! Shut the truck off and restart and it goes into gear. :mad: I get home and swap the back to modules and this time, the driver side does NOT work on the passenger but the passenger worked on the driver so I got the window back up. Coincidentally in all this, a rear module had gone bad?

11.) I will randomly get door dings and chimes after shutting off the truck. Sometimes nothing. (Auto Daytime Lights are on) I did notice today though, if I press my Fog Light button, it turns on and off my radio lights now! Even half of those work, as I can slam my fist on it and get the lights to swap working sides.

ALLLLLL that being said, if you've read this far I thank you. I think I've included...wait there was a nice stench for the past couple days as if a mouse has crawled up and died inside somewhere, probably chewed wires now that I think of it but this is 3 months later...Now that's all the details.

Any idea where to start a more accurate sleuthing point this weekend? Check the Gauge Cluster for corrosion? I've checked every fuse front and back. Do I need to try and find every ground, body ground, engine ground? I've read about data com splices but not sure what I'd do there other than check connections. 125 megafuse? DDM = broken wire ? yet I'm pulling voltage?

If this hits home for anyone that's come across a solution to any of these issues, I'd greatly appreciate advice or information. The truck itself seems to be running great now, it's just super electrically buggy!!

THE END
 
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#4 ·
I completely agree....

UPDATE: I got back to work this morning and just knew it'd fire right up after NOT starting last night, because of course this is how things with this truck have been going. Fired right up. For fun, I decided to check the back data cluster and the PCM to wiggle and just whatever....

Well, remember that stink I mentioned at the tail end of the novel? Mouse has gotten in there and nipped 2 wires on the cluster connection and chomped on the wires running down to the rear fuse box. For the time being I did a quick twist and tape to get it home and do a professional reconnecting job tomorrow.

It started right up with windows and locks and mirrors and gauges all working now!!!!
I'm not sure on the whole timeline thing, and I'm still sure the Fuel Pump issue was the external ground but I think ol Mickey Mouse has been causing me headaches for 3 months.
I'll update
 
#6 · (Edited)
I have yet to find said mouse, he's probably under the fuse box housing FRIED....I've got a full day at the shop today and just quickly put the wires together and taped to make it hope.
Started the truck and all the windows and locks work now and gauges seem to be correct. Hopefully this was the whole issue.

Tomorrow I'll do a pro job connecting and rewiring what he ate through. He will be found though!
 

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#7 ·
Well, weeks later seems everything is solved. The last time it died at my shop, I wiggled the relay around for S&G's and it started! Come to find out, the junkyard fusebox I had put in there had corrosion in pretty much every fuse slot as I pulled them all out and looked. Powder inside each connection.

I swapped back to my original fuse box and checked the wire connections underneath and closed the connector as best I could with an exacto knife so it'd make a better connection with the relay blade/connector.

It's started every time since. I believe I had a bad fuel pump ground to begin with, then piled upon the issue by trying that other fuse box and that created a new connection issue with the fuel pump relay.

Check them grounds folks!
 
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