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Old 08-21-2016, 07:29 AM   #18 (permalink)
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Join Date: Jan 2008
Location: SE USA - East Tennessee
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Josie - '87 Toyota Pickup
90 day: 30.49 mpg (US)

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EGR = Exhaust Gas Recirculation.

The engine control systems will pump a bit of exhaust gas back into the intake to give the engine something to inhale besides air. If things are running hot, or you are under low load, it means it can take in something that will fill the cylinder without adding too much air and leaning out the fuel-air mix.

I'm not sure where it is on your car but if it's a Honda then it's probably up front and pretty easy to see. There are LOTS of guys on here - myself included - who have taken on this simple maintenance step. Due to the nature of the gases it handles, the EGR is prone to picking up a lot of soot and schmutz and its passages getting clogged. When it's clogged, that means the EGR can't perform its usual function and then the engine HAS to breathe straight air, and the ECM has to pump in extra fuel to prevent the engine running too lean.

As to it being disconnected, there's electronic connects - just a single cable on mine, if I recall correctly - a bit of pipe and, of course, the gallery of passages routing gases from the valve to the intake runners. You'll take the valve itself apart of course, but don't forget the passages. If the valve itself is blocked at all, it's almost a sure thing the galleries - nice, long, cool galleries where gases can lose heat and velocity and gunk can condense against the walls - are going to be blocked too.

There's all manner of guys on YouTube walking you through the process. I had never done one before I did mine last year, and it took about an hour. No big deal.

DON'T FORGET TO REATTACH YOUR GROUND WIRES. Holy crap there are so many ground on a Honda and it will freak out if you don't get them all back on, nice and snug.

Budget-wise, if you're considering an alt delete and moving to a higher capacity battery, don't. Not yet.

Get a tank or two on your current configuration to establish a baseline. You're moving awfully fast already with your front belly pan on, but I wouldn't worry about that - I don't think anybody here will argue whether a belly pan is going to have an effect: it will, and probably a pretty good one.

Then f you're seriously thinking about changing the parasitic loads on the engine, do the power steering first. Remove the lines from the PS pump to the rack and loop the rack's hoses from the rack's input to the output. Then loop the pump's output back to the pump's input.

This will give the pump nothing to do. There will still be a bit of drag but nothing like what you're used to. The steering will feel heavy so don't let it surprise you. The only thing you've changed here is some plumbing and it's all reversible and you haven't spent a dime. Test carefully to ensure that everything works and you have reliable control.

Here's the fun bit: when you have an aerodynamically slippery car, making changes to the engine become pretty noticeable since they don't affect the car's aerodynamics at all and the noisy fuel economy of an aerodynamically messy car has been reduced. If you can get a pretty good baseline established with all the engine auxiliaries attached, then you should be able to spot pretty clearly what effect eliminating the PS has.

Lead or follow. Either is fine.

Last edited by elhigh; 08-21-2016 at 07:40 AM..
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