How do my spark plugs look?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Eighty5ov

Full Access Member
Joined
Dec 30, 2021
Posts
93
Reaction score
27
Location
Canada
First Name
Ov
Truck Year
1985
Truck Model
c15
Engine Size
5.7
Just got my 85 in the garage for some tests. It’s been running rough no power dying out sputtering. This a possible cause ?
You must be registered for see images attach
 

squaredeal91

Full Access Member
Joined
Mar 10, 2023
Posts
2,600
Reaction score
4,738
Location
Cave junction Oregon
First Name
Greg bush
Truck Year
1991 SB
Truck Model
K30
Engine Size
5.9 Cummins 12 valve
I see oil and carbon from poor running, If it's not smoking blue when driving then I'd look at ignition or carb.
 

PrairieDrifter

Full Access Member
Joined
Dec 28, 2014
Posts
3,880
Reaction score
5,717
Location
North Dakota
First Name
Mason
Truck Year
84,79,77,76,70,48
Truck Model
Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
Engine Size
350, 350, 350, 350, 350, 350
Rich and a little bit of oil, a couple gaps look small too.
 

PrairieDrifter

Full Access Member
Joined
Dec 28, 2014
Posts
3,880
Reaction score
5,717
Location
North Dakota
First Name
Mason
Truck Year
84,79,77,76,70,48
Truck Model
Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
Engine Size
350, 350, 350, 350, 350, 350

PrairieDrifter

Full Access Member
Joined
Dec 28, 2014
Posts
3,880
Reaction score
5,717
Location
North Dakota
First Name
Mason
Truck Year
84,79,77,76,70,48
Truck Model
Suburban k10, bonanza k10, k30, k20, c10, gmc 1/2ton
Engine Size
350, 350, 350, 350, 350, 350
They also could be really really old lol
 

Blackbeard44

Full Access Member
Joined
Jun 14, 2020
Posts
280
Reaction score
258
Location
Washington State
First Name
andy
Truck Year
1985
Truck Model
K20
Engine Size
6.0 LS
heres a good chart for future reference
 

Attachments

  • Spark-Plug-Reading-1024x933.jpg
    Spark-Plug-Reading-1024x933.jpg
    246.3 KB · Views: 40

Latest posts

Forum statistics

Threads
44,439
Posts
958,024
Members
36,810
Latest member
ProMod
Top