I did my Dad's 98 Blazer with 200,000 miles yesterday.
My main concern was the MAF sensor because my method of injecting Seafoam is with a spray bottle. I left the MAF connected; motor wouldn't run so I unplugged it and voilla, ran fine, albeit with the check engine light. So, on to the Seafoam. Since the throttle body opening is not horizontal, I rigged some extension hose onto the spray bottle intake tube so the bottle could stay vertical and I'd get a full supply of the good stuff. Then, sprayed away a full can as hard and fast as I could, and shut down and let it soak for 20 minutes. It smoked pretty good during the application but the motor never missed a lick. Meanwhile, I undid the battery to clear any possible MAF code.
Went for a drive, hardly ANY smoke.
Motor was hot and everything.
But the improvement was simply amazing. I've talked about this truck; it is a pinger like you wouldn't believe! DEATH RATTLE of a ping, even on a 50 degree day, although it sounds and acts much worse in the dead of summer. Now, hardly any ping at all and you can feel the timing not being retarded. Mileage on the trip computer was a tick over 19 from just a few around town errand runs. Idle is smooth as glass from being fairly rough and shaky. WOW!! I just hope it stays this way. Seafoam is gonna be a yearly maintenance item for me now.
My main concern was the MAF sensor because my method of injecting Seafoam is with a spray bottle. I left the MAF connected; motor wouldn't run so I unplugged it and voilla, ran fine, albeit with the check engine light. So, on to the Seafoam. Since the throttle body opening is not horizontal, I rigged some extension hose onto the spray bottle intake tube so the bottle could stay vertical and I'd get a full supply of the good stuff. Then, sprayed away a full can as hard and fast as I could, and shut down and let it soak for 20 minutes. It smoked pretty good during the application but the motor never missed a lick. Meanwhile, I undid the battery to clear any possible MAF code.
Went for a drive, hardly ANY smoke.
But the improvement was simply amazing. I've talked about this truck; it is a pinger like you wouldn't believe! DEATH RATTLE of a ping, even on a 50 degree day, although it sounds and acts much worse in the dead of summer. Now, hardly any ping at all and you can feel the timing not being retarded. Mileage on the trip computer was a tick over 19 from just a few around town errand runs. Idle is smooth as glass from being fairly rough and shaky. WOW!! I just hope it stays this way. Seafoam is gonna be a yearly maintenance item for me now.
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