2003 with 210K on the odometer, bone stock.

Just got a "service engine soon" light. Checked my GP ohms off the green and black plug after disconnecting from GPCM.

For green plug:

1.5 ohms
1.4
1.3
1.4

For Black plug:

2.1 ohms
2.1
2.2
3.2

1. Is it ok to test off plastic green and black plugs from GPCM?

2. Is it strange one entire bank is consistently higher than other bank?

3. What is considered too high for ohm reading?

4. If I change GPs, will it fix SES light or should I check GPCM too?


thanks

 

If you've got a UVCH working it's way loose, that could explain the higher readings on one side. If it's a glow plug code that was tripped, you can likely get it read by one of the free scans from the auto parts stores. I'd start with that and see what codes it comes up with.

If it's a UVCH issue, the free scan won't pick up that code, but if it gets worse you'll figure it out because the truck will start running rough.