MPG dropped dramtically
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MPG dropped dramtically
Hey guys,
Any of you lose mpgs after seafoaming?!?! I seafoamed over the weekend with great results. Truck runs, sounds, and feels better but noticed she's drinking a lot faster! I was getting 16mpg and proabably way below that now. I have actually never payed attention to what mileage i get in total off front and rear tanks. But lets put it this way.... i went through half a tank in 2 days doing my daily drive to work and back home....and then the corner store 5 blocks from my house. Half a tank can last me up to 3-4 days depending how heavy my foot decides to be that day. I also have a faulty TPS, which was prior to seafoam. Mind you, after seafoam my warm idle is high now. Is this decrease from the seafoaming or tps!?
Any of you lose mpgs after seafoaming?!?! I seafoamed over the weekend with great results. Truck runs, sounds, and feels better but noticed she's drinking a lot faster! I was getting 16mpg and proabably way below that now. I have actually never payed attention to what mileage i get in total off front and rear tanks. But lets put it this way.... i went through half a tank in 2 days doing my daily drive to work and back home....and then the corner store 5 blocks from my house. Half a tank can last me up to 3-4 days depending how heavy my foot decides to be that day. I also have a faulty TPS, which was prior to seafoam. Mind you, after seafoam my warm idle is high now. Is this decrease from the seafoaming or tps!?
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Joined: Apr 2008
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Replace your TPS, then worry about what the seafoam may or may not have done. The PCM uses the TPS to determine how much fuel to deliver in the cylinders, when TPS ain't right the PCM may go into keep-alive mode and just pour fuel in to make sure no matter what you won't stall... Which is probably what's going on right now.
Logistics Pro
Joined: Mar 2005
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From: Mexico, Missouri
What everyone said.
Then you could have the dreaded fuel pump FDM going bad, as in my case, when I was driving on the rear tank and then went to somewhere later that day and next it was pumping into the front tank.
Then you could have the dreaded fuel pump FDM going bad, as in my case, when I was driving on the rear tank and then went to somewhere later that day and next it was pumping into the front tank.
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Well...I've taken my heavy foot into account but can't move anywhere too fast with traffic so I'm positive my driving pattern hasn't changed. I'm leaning towards the TPS, as my idle is high now (1200rpm) and fuel is just getting dumped in at idle. I picked up a new TPS and will be replacing it soon. I use the same gas as always, Mohawk 91 octane. Will let you guys know what happends. Thanks guys.
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From: Charlestown, RI
Well...I've taken my heavy foot into account but can't move anywhere too fast with traffic so I'm positive my driving pattern hasn't changed. I'm leaning towards the TPS, as my idle is high now (1200rpm) and fuel is just getting dumped in at idle. I picked up a new TPS and will be replacing it soon. I use the same gas as always, Mohawk 91 octane. Will let you guys know what happends. Thanks guys.
Also, the high idle after Seafoaming, I'd check to make sure you don't have a vacuum leak. This would account for the high idle, and lower fuel mileage.
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No vaccum leaks from what I can see, I traced all the lines possible. However, i got a code thrown at me about my canister purge (coffee can) that wouldnt effect it do you think?
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From: Charlestown, RI
A purge code would most likely be for the charcoal canister purge valve, different than the coffee can. I get that code from time to time as well, but haven't had a chance to dig into it yet.
Maybe try spraying some carb cleaner around the line you removed to put the Seafoam in, and just double check for leaks?
Maybe try spraying some carb cleaner around the line you removed to put the Seafoam in, and just double check for leaks?
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A purge code would most likely be for the charcoal canister purge valve, different than the coffee can. I get that code from time to time as well, but haven't had a chance to dig into it yet.
Maybe try spraying some carb cleaner around the line you removed to put the Seafoam in, and just double check for leaks?
Maybe try spraying some carb cleaner around the line you removed to put the Seafoam in, and just double check for leaks?
I used the brake booster line for the seafoam. I double checked all my lines and cleaned the vaccum tree as well out of interest.
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Location depends which engine you have. On my 302, it's in the front, below the throttle body. Mine isn't attached to a bracket or held by anything (not sure if it's supposed to be). You'll see two vacuum lines, and an electrical connector on it. One end goes to the manifold, and the other one goes to the charcoal canister.
Speaking of the coffee can though, check that as well. Mine looked great on the topside, and the bottomside was rotted through, causing a vacuum leak.
Speaking of the coffee can though, check that as well. Mine looked great on the topside, and the bottomside was rotted through, causing a vacuum leak.