Just some thought for you to investigate since you like tinkering on the truck...(this should keep you busy for a while...)-
When you’re chasing incremental gains, you have to have to be vigilant in finding and eliminating parasitic drains on the power that the engine makes (or isn’t making). Things like tire pressure (rolling resistance is the enemy) can have a surprisingly significant effect on efficiency. Another thing you might want to look at is grounding - if the sensors are limited by a smaller range of readings, you might not be getting the most out of the groove. Same applies to the power side of the electrics - is the alternator strong? Is the Serpentine belt stretched/slipping? Is the belt tensioner doing its job? Is the battery able to hold and deliver proper power?
Thanks for the feedback .I have been noticing the battery light comes on in the morning for about the first mile.i need to see if it's the alternator or the battery.that may be holding up a lot.just haven't thought about that.i do have 44 in the back tires and 46 in the front .they say 44 on the side.the belt and pulleys seem good also the ground and positive are clean and tight.i used aluminum foil wrapping the exhaust it only about a foot from the manifold to the catalytic converter so I don't know if it's a big help or not.ive not got to the plugs yet to open them up.thanks again!
That sounds more like a battery problem than an alternator/charging system problem - but you may have a small drain somewhere in your power system, that discharges the battery while it's parked overnight. both are things to chase down.
once you do and repair the issue, you might want to think about this:
remember that the battery acts not only as storage, but also as a capacitor to smooth power delivery from the alternator to the rest of the vehicle when it's running. that 4th wire (especially if it's a small gauge) strengthens the ground in the vehicle, and all systems will benefit - including the ignition. you may not think that half a volt might not make that much of a difference, but it may make a HUGE difference when you get around to opening up those spark plugs...and we ARE talking about chasing parasitic drains on engine power for increasing gains by a couple of MPG, right?
Good luck!! I'm betting on a new best of 21 MPG once you get this sorted - if the battery discharges enough overnight every night, you might be doing a re-learn every morning
The following user(s) said Thank You: Tracy Gallaway, CLAUDIO CORDOVA
Miles- in the morning, put a voltmeter on the battery. A fully charged battery at rest will show 12.65 volts. 12 volts is discharged. Look at the cables for open areas in insulation, for copper showing- esp. for corrosion visible in the cable. Besides having clean terminal-post connections ON the battery, also look for dirty corrosion crud on top. That dirty accumulation is conductive. IF you see that crud on top, put the + Voltmeter lead on Batt. + post, then probe around the batt. top w/ the voltmeter -- neg. lead. You'll likely see voltage on the meter. When that dirt crud reaches both batt. posts- it forms a conductive path. This leads to the battery slowly discharging itself!
If the battery cables show wear, corrosion, open insulation, consider replacing as needed. I've replaced worn Negative cables before ( and added an extra body or chassis ground wire at the same time)-- and seen Immediate improvements in battery and charging system condition.
It's easy to overlook the simple stuff w/ the battery and cables, but those little thinks really matter. Cold weather is coming, Git 'Er Done, Podner!
Founder and Constant Aide to Gadgetman
Gadgetman Reno, NV
You were right i had a bad battery .anyway im still running the rvs in motorcraft 5-20 blended synthetic then wanting to try 100%synthetic royal purple like mike hollor says he likes best.do y'all think it will be ok with 204000 miles on it.its a 2007 f150 supercrew with the 4.6. Still getting 17 mpg and love it.i did find a parasitic draw from the power point in the back and the maplight kelpt shooting my fuse.i still have a while before the oil change.just planning ahead.ive tried the mpgr with 12 non coated aspirin and one ounce of 190 everclear and half ounce of hydrogen peroxide in a thirty gallon tank.couldnt tell anything cause I may have not used the right amount.but I'll keep at it.
You dissolve the aspirin in the peroxide (food grade, not the stuff from the drugstore) and then add the everclear, pour into the tank and then fill up.
As far as switching to synthetic oil, it makes for easier starts especially in colder weather. You may find some leaks, but they need attending to anyway. I’ve found synth oil to not make much of a difference in mileage, but for cold starts and faster warmups to close loop, it’s great. Watch your levels/consumption/leaks for a while, but generally the benefit is extended change intervals and easier cold starts/faster to closed loop in the approaching colder weather. (I was just shopping today for a heater I can attach to my oil pan in addition to my block heater to help with winter starts and reduced time to closed loop)
The following user(s) said Thank You: Michael Lee, CLAUDIO CORDOVA, Miles
I had a bad alternator to apparently while I had it off I took off the tb and noticed the factory gasket was blocking the groove a little so I removed all the little fins on it an tooled it back smooth held it up to the tb and grooved it as to cut the plastic on the gasket we will see if it makes a difference after a few tanks.ill try to post pictures.
This message has attachments images. Please log in or register to see it.
The following user(s) said Thank You: Ron Hatton, Tracy Gallaway, Michael Lee, CLAUDIO CORDOVA
Thanks Miles! I wonder just what Ford had in mind w/ those vanes? Looks like trying to "comb" the flow. Question is- trying to straighten flow, or induce turbulence? Or both? Look how those vanes end abruptly, a flat downstream edge. Seems to me those flat edges will cause a low-pressure zone immediately downstream, behind 'em.
Look up Airtab.com , more info re. low pressure area behind those flat edges...
Founder and Constant Aide to Gadgetman
Gadgetman Reno, NV
I know that's weird right it seem to be getting around 18 city now just buy looking at the obd2 have not refilled tank yet I'm curious also.any Ford's 2007 should watch for that.i think it has done better.buy the way a 45 dollar alternator from the junk yard seems better than $200 from the parts store. Thanks for talking to me Ron and all of y'alls feed back.
The following user(s) said Thank You: CLAUDIO CORDOVA