Electrical problems

Tiny
PAUL ALLRED
  • MEMBER
  • 1998 CHEVROLET 1500
  • 5.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 250,000 MILES
I just swapped everything from 1998 k1500 onto 1996 k1500 frame. 1998 had frame damage. 1998 was running fine before the swap and now it has gone from a start and immediate stall out (quicker if you press gas). I since have checked the harness and made sure plugs match. Made sure ground is going from battery to front of motor beside timing chain and to fender. The next one go's from the second bolt on the head on passenger side down beside starter to frame. The third from right below the heater coil hoses to same bolt on frame as the second ground. Now the problem has become a want to start then chatter from solenoid like low power plus doors lock unlock, erratic gauges. What are your thoughts on this? I suspect that the 2 grounds #2 & #3 are not supposed to be grounded together.
Monday, January 6th, 2020 AT 5:11 PM

11 Replies

Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello,

This actually sounds like a bad body ground. I would recommend checking Ground 202, which is located behind the left side of the instrument panel. Ensure that the ground is clean, tight, corrosion free, and making good metal to metal contact. In the diagrams down below I have included the wiring diagrams for the instrument cluster, power locks, and a ground distribution wiring diagram for a 1996 Chevrolet K1500 truck with a 350 C.I.D. Power plant. Please get back to us with what you find out.

Thanks,
Alex
2CarPros
Images (Click to make bigger)
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
+2
Monday, January 6th, 2020 AT 7:08 PM
Tiny
PAUL ALLRED
  • MEMBER
  • 12 POSTS
I never disconnected anything inside the truck. Only the outside. I pulled fuses and when I pulled IGN A which is a large 40a fuse everything stopped. I replaced and pulled smaller fuses. Eng E, ECM 1, ENG 1 were the 3 that stopped everything. I replaced all other fuses except the 3 and no flashing or noises. I put just 1 of them in and something acts out. It may be the interior lights, fuel pump relay clicking or doors clicking. I disconnected 2 ground straps from the frame (one below the heated core hoses on pass firewall, other on rear pass head). The one on the thermostat and one I'm not familiar with that is on a harness that's been looped (from the rear firewall) I left the other at the fuel tank and the 2 at bottom front of motor that contain the battery and another ground. I don't have the rear bumped and lights on yet not the front. I have wire brushes and sanded all the bolts and connecting point along with the connectors. Those are the outside grounds I have. Truck was running fine before the swap.
One other thing. I don't understand I believe G119. In one spot it says near thermostat housing on same page it says on front of block. I know both spots. Is the engine whole engine referred to as G119?
Was this
answer
helpful?
Yes
No
+1
Wednesday, January 8th, 2020 AT 5:14 PM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello,

I understand that you didn't do anything to the inside wiring, but isn't there the possibility that this ground was bad when you installed this engine into the chassis? This is a common ground to all of the systems that are malfunctioning. You did not do this, but it was an unknown pre-existing condition. Please get back to us with what you find out.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
+1
Wednesday, January 8th, 2020 AT 7:39 PM
Tiny
PAUL ALLRED
  • MEMBER
  • 12 POSTS
Do you have a diagram that shows illustrationto where these grounds are located? I found a ground on the side of the e-brake pedal but I dont think this is the G202 you are referring to.
Was this
answer
helpful?
Yes
No
+1
Friday, January 10th, 2020 AT 12:28 AM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

I can't find a diagram of the ground for you in our reference material. The description from the ground distribution wiring diagrams says that it is located behind the left hand side of the instrument panel. This is about the best I can do for you.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
+1
Friday, January 10th, 2020 AT 4:36 AM
Tiny
PAUL ALLRED
  • MEMBER
  • 12 POSTS
Okay. I'm in luck. I just found the tech service manual for my truck. Omg the pages. I have found one problem. I will include a pic. It is of G103 and G150. I cannot find any reference to what G150 is.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
+1
Saturday, January 11th, 2020 AT 5:59 AM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

Okay I have found a diagram showing the location of ground 202 and one showing the location of ground 150 for you. I have included them in the diagrams down below for you. I hope this helps and report back with how everything turns out please.

Thanks,
Alex
2CarPros
Images (Click to make bigger)
Thumb
Thumb
Was this
answer
helpful?
Yes
No
+1
Saturday, January 11th, 2020 AT 7:36 PM
Tiny
PAUL ALLRED
  • MEMBER
  • 12 POSTS
I found g202. Inspected the connection and the wires. Everything looks good. G150 on the other had. No luck. There is no reference to where it is coming from in the Chevrolet workshop book I have. Still have the major electrical problem. Could it be that I don't have enough grounds and that when I turn the key or supply power its making the system act out?
Was this
answer
helpful?
Yes
No
+1
Monday, January 13th, 2020 AT 10:24 AM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

In the second diagram I sent last time it shows where Ground 150 is located. Sorry for taking so long to answer, I am just getting over the flu.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
+1
Tuesday, January 14th, 2020 AT 5:24 PM
Tiny
PAUL ALLRED
  • MEMBER
  • 12 POSTS
I got figured out my short problem. It was a white wire that I grounded to the rear frame. Problem solved. Now the new problem is. It will start and run but shuts off almost immediately. Like I turned the switch off. The security light does come on but goes right back off after about 5 or so seconds. I put a jumper from 30 to 87 on fuel relay and pump does run and will start the truck but still shuts off. I tapped a jumper on the oil press sending unit connector and I do here it click on. My thinking is that something isn't telling the injectors to pull the fuel. Oh, fuel pressure is 65 psi and strong. Even when cranking it only drops maybe 2-3 psi. So I have a start but not staying running condition.
Was this
answer
helpful?
Yes
No
+1
Wednesday, January 15th, 2020 AT 5:10 PM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

I would be happy to help you with this problem but for archival thread purposes we ask that you please ask this as a separate question. This is so if another customer has a similar problem they can be able to look the new thread/question up from the archives.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
+1
Thursday, January 16th, 2020 AT 4:13 AM

Please login or register to post a reply.

Related Timing Chain Content

Timing Set and Front Cover
VIDEO
Timing Set and Front Cover
In­struc­tional re­pair video