Wet plugs on passenger side

[DougN2deep]

I've got a '93 K1500 I bought in '20. I was after the camper that was on it and the guy said he'd give me a good deal on the truck. He said it had a new rebuilt top end and had been well taken care of. She's got 187k and I've only put about 400 miles on her.

I bought some bigger off road tires for her to grab wood in the mtns and some bigger front brakes/rotors (still need to install).

Took her out a few times in the last month and the acceleration has been boggy with some misfires/back fires.

Pulled the plugs and all the passenger side plugs are wet w/oil. Did a compression test and all the cylinders are pretty even between 170-180 and one at 150. Replaced the plugs and no change. Pulled the air filter and the TBI spray looks erratic and not like an umbrella. Tried hooking up an OBD1 and no codes.

Ordered a fuel filter,fuel pressure gauge,and distributor cap 'n plug wire for piece of mind.

Guy at Napa said likely none of the above as the passenger side plugs are wet. He'd said to check out the injectors.

Any input you guys can offer would be great. I'm getting a but in over my head, but have tools.

 

[Scooterwrench]

Those plugs are not oiled down but I see a couple that are fuel fouled. They all show rich. It could be the wires,cap and rotor not passing the secondary voltage to the plugs. If it is still running rich after replacing those parts then you may have an injector sticking open. I'm guessing someone told you that turning the air breather lid upside down will give it more power. All it does is collect more debris.

 

[DougN2deep]

Those plugs are not oiled down but I see a couple that are fuel fouled. They all show rich. It could be the wires,cap and rotor not passing the secondary voltage to the plugs. If it is still running rich after replacing those parts then you may have an injector sticking open. I'm guessing someone told you that turning the air breather lid upside down will give it more power. All it does is collect more debris.

Thanks for the response

I'm gonna swap the wires/cap when the snow passes, likely next week.

The air breather came like that, and yet it does catch debris lol.

You see any other mods done? My first k1500. I like the truck a good bit, this was the truck to have in high school.

 

[movietvet]

If the fuel is going in by drops, instead of a nice cone spray, that is not good. Is that on both injectors or just one?

 

[GoToGuy]

I would add to your list, cleanup the mess on the battery terminals so there won't be a problem that happens away from home , at night , with no cell service and starting to rain.
Is that a loose hot power wire ? Changed oil and filter with quality filter? Transmission filter and fluid? Transfer case? Both front and rear axle fluid?
With unknown history its a a way to cover your bases. Start a new service interval history.

 

[Orpedcrow]

Spark plug wires look like they might be original? Bet the ignition tune up will be well worth doing

Share pictures of the cap and rotor when you get them off.

Those big red power wires are poorly run and have no fuse that I can see.

 

[DougN2deep]

If the fuel is going in by drops, instead of a nice cone spray, that is not good. Is that on both injectors or just one?

Both injectors look like they're not running steady. Lot of gas but not even.

 

[PlayingWithTBI]

Guy at Napa said likely none of the above as the passenger side plugs are wet. He'd said to check out the injectors.

If it was one injector, you'd have 2 center plugs on one side and 2 outside plugs on the other. That's how the intake manifold is made.

 

[RichLo]

Check the fuel pressure, you could have a weak regulator spring. You can buy a schrader valve adaptor that goes between the throttle body and fuel inlet line.

As for the wet plugs on just 1 side, thats a mystery but like everyone else said, start with a fresh service history and replace all of the common 'tune-up' stuff first.

 

[DougN2deep]

Check the fuel pressure, you could have a weak regulator spring. You can buy a schrader valve adaptor that goes between the throttle body and fuel inlet line.

As for the wet plugs on just 1 side, thats a mystery but like everyone else said, start with a fresh service history and replace all of the common 'tune-up' stuff first.

Been watching how to swap out the fuel injection pressure regulator and injectors and it looks fairly easy. If I'm in there already should I replace them along with the gaskets? Looks to be about $160 in parts.

Starting the fresh service history today if the snow stays away.