SC300 Spark Plug Info (long)
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Just a brief note for those who know how to use the search function. This basic info could have saved me over an hour searching.
1. Cylinders are 1 - 6, front to back, front being closest to Radiator.
2. Remove the valley tray that runs the length of the engine, on top of the plugs, before removing the plugs. I almost dumped WATER into my engine.
3. Men with a size 14 ring finger, DON'T need to be working on these cars![Egads!](https://www.clublexus.com/forums/images/smilies/pat.gif)
Let me explain......Daughters car began running ruff, hesitating, down on power after I had it inspected. The car passed with flying colors, inspection guy said the numbers were really low for a 17 year old car
. In Texas, they put the vehicle on rollers like a dyno to get the exhaust readings at 15 and 30 mph. Being a rear wheel drive, it was at an angle sloping to the front of the car, took about 15 minutes from start to finish, car running the entire time. Drove off and went to fill up. Gas Station is always busy, so they turn their fuel over quickly. I drive home (about 10 minutes) daughter drives off to pick up boyfriend. She gets home and says it was running ruff and jerking when she tried to accelerate. We go to a formal function in Houston, and when she gets there she tells me that it is running really bad. I drive it home later that night, notice some slight hiccups, but nothing as bad as she described.
Wednesday I drive it to have the door handle fixed (Thnks GS300), and it is running HORRIBLE. Will barely accelerate up to speed. I immediately think bad gas. Tank is at a half, so I fill up at Chevron with a can of seafoam. Stop and get a fuel filter from NAPA and head to a local garage. Oil change monkey gets assigned the fuel filter change, and after about 2 gallons run out, he gets it done. Still no change, idle ruff etc. I am working nights so I have to park it until friday.
I have plugs from earlier when I didn't change them (water Pump job) so I digg in. Get ready to change #6 plug first, put in the socket and something tells me to take it back out. It is covered in a mixture of oil and coolant
. So I take off the valley tray (it covers the spark plugs) and #5 and #6 have about 3.5 inched of this goo floating around in the space. #3 and #4 dont look much better, and #1 and #2 have staright oil in their valley area. After cleaning everything, I start to look for the water source, and quickly discover it is the heater hose at the back of the engine. After darn near tearing my knuckles off, I finally get the hose off, and there is a very easy to see split. Car had been slowly loosing coolant for a while, but I just installed a new overflow tank and was hopeing that had cured the problem.
To end this saga, I figured that at the inspection station, with the car sitting and running with the nose down and rear up, it had filled up the galley of plugs 5 and 6, and one or both were misfireing causing the car to run bad. Aside from loosing coolant, the car has been running great. Mileage was maybe a little low (15.5 last check, 100% city driving). New plugs, wires (they crumbled when I pulled them off), cap and rotor and the car is ideling like a kitten again. It amazed my how these cars can go from running fairly well one day to total crap the next. It never thru ANY codes!!!!!
Be vigilant with the Maintenance my friends.....
Jim
1. Cylinders are 1 - 6, front to back, front being closest to Radiator.
2. Remove the valley tray that runs the length of the engine, on top of the plugs, before removing the plugs. I almost dumped WATER into my engine.
3. Men with a size 14 ring finger, DON'T need to be working on these cars
![Egads!](https://www.clublexus.com/forums/images/smilies/pat.gif)
Let me explain......Daughters car began running ruff, hesitating, down on power after I had it inspected. The car passed with flying colors, inspection guy said the numbers were really low for a 17 year old car
![Big Grin](https://www.clublexus.com/forums/images/smilies/biggrin.gif)
Wednesday I drive it to have the door handle fixed (Thnks GS300), and it is running HORRIBLE. Will barely accelerate up to speed. I immediately think bad gas. Tank is at a half, so I fill up at Chevron with a can of seafoam. Stop and get a fuel filter from NAPA and head to a local garage. Oil change monkey gets assigned the fuel filter change, and after about 2 gallons run out, he gets it done. Still no change, idle ruff etc. I am working nights so I have to park it until friday.
I have plugs from earlier when I didn't change them (water Pump job) so I digg in. Get ready to change #6 plug first, put in the socket and something tells me to take it back out. It is covered in a mixture of oil and coolant
![EEK!](https://www.clublexus.com/forums/images/smilies/eek1.gif)
To end this saga, I figured that at the inspection station, with the car sitting and running with the nose down and rear up, it had filled up the galley of plugs 5 and 6, and one or both were misfireing causing the car to run bad. Aside from loosing coolant, the car has been running great. Mileage was maybe a little low (15.5 last check, 100% city driving). New plugs, wires (they crumbled when I pulled them off), cap and rotor and the car is ideling like a kitten again. It amazed my how these cars can go from running fairly well one day to total crap the next. It never thru ANY codes!!!!!
Be vigilant with the Maintenance my friends.....
Jim
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