First Start - no crank condition...
- Thread starter Nilbog
- Start date
Running!!!! Thanks ya'll!! 
I ground off powder on all ground points. Connected headlight harness ground to transmission. Ran another ground wire so that ALL ground connection points were connected by cable, not relying on chassis continuity. Fired right off....
I ground off powder on all ground points. Connected headlight harness ground to transmission. Ran another ground wire so that ALL ground connection points were connected by cable, not relying on chassis continuity. Fired right off....
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ctuinstra
Goblin Guru
Basically grounds?
Happens often. Electricity doesn't pass through paint and powder coat (especially powder coating). I ground off all the powder coating on the underside of the engine mounts of the frame so metal is touching metal. Also did the same thing with the pedal box and the grounds around it. Very good grounds make for a trouble-free electrical system! Oddly, the donor Cobalts were plagued with poor grounds! Tiffany's car had bad ground and the door locks would work on/off by themselves. I couldn't figure it out until I replaced the engine and found the ground on the transmission to be terrible. After cleaning up all of the ground and swapping out the engine, she never had an issue with the door locks again.
Happens often. Electricity doesn't pass through paint and powder coat (especially powder coating). I ground off all the powder coating on the underside of the engine mounts of the frame so metal is touching metal. Also did the same thing with the pedal box and the grounds around it. Very good grounds make for a trouble-free electrical system! Oddly, the donor Cobalts were plagued with poor grounds! Tiffany's car had bad ground and the door locks would work on/off by themselves. I couldn't figure it out until I replaced the engine and found the ground on the transmission to be terrible. After cleaning up all of the ground and swapping out the engine, she never had an issue with the door locks again.
Karter2026
Goblin Guru
80% of 12v problems are ground problems. I had the same no crank issue after I painted and reassembled the car and engine assy. It cranked and everything worked during mock up. So it did not take me long to check grounds and fix the issue. I ended up grinding the paint off and welding a ground stud on the angle above the fuel tank. I did not like it bolted up to one of the spare holes in the transmission mount. There is already enough wires in that area.
Briann1177
Goblin Guru
Hard to diagnose, but easy to fix. Grounds can be weird. Sometimes I'll poke around for fun and I'll get 12V using a ground that I have no idea how it is even grounded to begin with.
Glad you fixed it.
Glad you fixed it.
IDRVSLO
Goblin Guru
Congrats brother!
Christopher Sanchez
Well-Known Member
My ground also seems to travel through the harness to the ground lug (unless I cut it). Did you end up cutting and grounding this wire to the frame? My goblin currently has a no crank condition. I Have not cleaned up the powder coat from the trans/motor mounts yet, that will be next on my list but am curious about what you ended up doing. (my dash lights,fuel pump, throttle pedal and clutch sensor all seem to be functioning)
ctuinstra
Goblin Guru
Before you clean the powder coat from the mounts, do you have the large ground cable that was originally bolted to the engine/transmission? Use that to ground to the frame. If not, try a jumper cable from the negative of the battery post to block of the engine.
If you are getting the throttle to move when you first turn the key, the data wires are fine. I can't help to wonder if you just don't have a good ground to the block and therefore the starter has 12v but no ground.
Christopher Sanchez
Well-Known Member
Yes I do have the large ground on the trans side I believe I grounded it to the frame already. It seems as though I have extra sets of ground lugs. I have the pedal box grounds, then one that grounds to the floor support bolt. I have an additional set of lugs further back in the tunnel box. Is the normal for the TCs? I have an extension grounding that to the Engine/frame bolt. Now this is just temporary but was hoping to hear it run before finalizing everything. Another piece of info, I can use a jumper wire from the pos + terminal to the starter and it will crank. Thanks for the ideas. I am currently on a long stretch at work but will try to find a sec to check the grounds in the AM.
Christopher Sanchez
Well-Known Member
Yes, mine looks a little different if I remember correctly, but yes a connector with a purple wire
Reviving this thread. I have the same problem, and I've been working on it for 2 days now. Key to the run position, gauges wake up, throttle moves, fuel pump runs. Turn to the start position, a relay on the BCM clicks and nothing happens.
I have tried:
I'm stumped. The car started and ran fine when I got it. Any ideas?
I have tried:
- Grounds.
- I cleaned the paint/powder coat off of the engine and frame where they touch and at each ground connection.
- Continuity checks at each ground point are good, between the frame and each other.
- I tried connecting a cable to the negative terminal of the battery and to each ground point individually. No changes.
- The ground in underhood X3 (headlight plug) is attached to the block.
- Continuity
- I checked continuity between each of the connections in the attached photo.
- High speed GMLAN from BCM to ECM is good.
- All green wires that were left in the harness are soldered together.
- Jumping
- The engine turns over when jumping pins 87 and 30 on the CRNK relay.
- Switches
- I checked continuity between the clutch switch and the fuel pump as well as it's other connections. It also has a 5v signal.
- No combination of clutch/brake positions has any effect. You can hear a relay click when stepping on the brake.
I'm stumped. The car started and ran fine when I got it. Any ideas?
Attachments
Christopher Sanchez
Well-Known Member
When I thinned my harness somehow I cut the clutch position sensor at the pcm plug. Apparently others have came close to doing the same so idk if the videos have a misleading step when doing a Turbo kit..
ctuinstra
Goblin Guru
You said is has 9.6v (which is a very odd voltage). Did you measure that using frame ground or 85 on the relay? Can you tell if that relay even clicks?
From everything else you said, everything seems to be fine, especially with the date lines. We need to focus on why that relay is that way.