Correct D15Z1 leanburn info

[VxonFumes]

Greasemonkee...

I tried looking for a link you may have left when you converted your car, but couldn't find one. Would be interested to see all you did.

Mine's just bone stock, so far.

thanks

[greasemonkee]

Fixed, sorry. Recently deleted all of my NSA spy (google) accounts and it wiped out the youtube links.

It's at the bottom of the first post.

[VxonFumes]

You had to delete all your NSA spy accounts! Lol!

I saw your vids finally...lot of gauges floating around the cockpit. If I were driving your car I'd have a hard time resisting the urge to flip a few switches and start the countdown to blast off. In other words...very cool.

Noticed your vacuum gauge showed 21 inches of mercury at idle. That's very good...and makes me wonder about mine. My car idles with about 18 inches of Mercury. I *think* my engine is still very sound and tight, and I can't find any vacuum leaks anywhere. I just have a cheap Chinese gauge though...can't comment too much on it's accuracy, but I think it's pretty good. Would 18 inches of vacuum bother you? Hopefully I can find a way to get a compression test done on it.

Also, when almost WOT going up that hill at 13.5 Air Fuel Ratio, did you ever encounter anything close to detonation?

Also, since you seem to know what you're doing...what are your thoughts on this. The idle air control valve has gone to pot on Ed, and has a mind of it's own...sometimes dropping down to 500 rpm, other times it won't go down when you let off the throttle, it actually continues to rise. (no, not stuck throttle cable.) It's a cheap aftermarket part that worked perfect at first, but is already crapped out after one year. Basically, as I see it, the iacv functions almost as a kind of choke, even though that might not be it's primary function. And when it's acting up, the faulty iacv could actually be enrichening the mixture unduly, right? So I'm thinking, once I get the new OEM Honda valve in place in a couple weeks, that theoretically could improve mileage. Thoughts?

I would like to do your mod where you widened the parameters for lean-burn initiation, but that procedure is a bit above my skill level maybe. I am trying to figure out if you're a mechanic or engineer by trade. Or both? I'm a little worried about long-term longevity with such mods, but lean-burn extension seems like a relatively risk free mod, so long as it's done right. It's not like you're adding 20 pounds of boost. How much extra torque would you guestimate the mod gave you? Any downsides in driveability? And you think it gave you an extra 2 mpg?

What I would like to do is rig up a small led light that glows green when lean burn is active...but scared to splice wires into the ECU harness.

Nice work on the car. Ever break your magical 60 mpg barrier yet? I just today, got my best tank ever, at 56.74 mpg, and I think there is still quite a bit of room for improvement, if only my finances would improve first...

[VxonFumes]

few more things greasemonkee...

I just now found your photos of your civic and van...and had to comment. This is uncanny...not only do we have the same car, but we also have a navy blue 98 odyssey! I once got, on our best tank, 930 kms on 60 liters of fuel, or, 36 mpg. That was with low rolling resistance Ecopia tires, top tier Amsoil fluids in everything, and air-tabs on the rear of the vehicle, and not other mods.

Few more questions...sorry to keep nailing you with emails like this. But what is that canister in the front fender area of the odyssey? Also, what did you do to the PCV canister on the VX with the extra thick tubing? Also, I saw metal threaded plugs...did you clean out the intake manifold on your car and plug it with those?

what kinds of headlights are on the odyssey? And what on earth did you do to the exhaust on the...odyssey? (two divergent pipes.) Lots of curiosity going around here!

[greasemonkee]

Initially I had a problem with the EGR valve. The valve itself was moving properly, but the old, hardened grease in the sensor was holding that part of it in the open position. The ecu saw this as the valve being open, thus adding a LOAD of timing, finally resulting in detonation that couldn't be remedied even with 93 fuel. After cleaning and regreasing the sensor the problem went away. The fuel controller artificially changes the map signal which changes timing - adding timing in this case. Without having a timing light and watching it under a load (impossible without a dyno) the best I could do was make an educated guess. Ultimately removing a few degrees from the distributor was enough to offset the ecu timing change.

So to answer the question directly, there was no detonation at 13.5 AFR, however it may become more sensitive with too much lead timing at those AFR's. Nevertheless, sure beats 11.8 AFR.











The iac valve is nothing more than a bypass valve to let air around the throttle plate that operates on duty cycle (pulses sent from the ecu). This shouldn't effect economy unless you're really idling high; it has no way of changing the fueling directly. There are a lot of these around - the same on most all D series engines I think. If you want , I may have one on the shelf.




The fuel controllr did give me an increase of about 2 mpg, not from leanburn expansion alone, but leaning the wasteful WOT maps and target lambda. This is a neat system btw, always remains in closed loop when at operating temp.

A light would need a little circuitry I believe, but possible.



Not sure what you speak of on the diverging pipes on the odyssey - haven't touched it - the civic, yes, it's got a DX exhaust manifold. The metal plugs and hose is probably the train horn. Eventually I had enough of people running me off the road because they could see the car. There is only one vacuum tank in place to prolong the power braking during coast.


Metal plugs - ahh, you must be talking about the magnetic oil drain plugs? I make those.


With skinny 185 tires, the car was kissing 60, but difficult. The mountainous terrain require a lot of hard braking - 1000' to 4000' back down to 1000' up and down up and down. On flat road 60 would have been easy. These days I opt for the handling rather than that extra mpg and run the 195-50-15's. The extra speed carried through the curves without having to brake compensates a little.


Haven't really modified the odyssey other than the aero. Just bought a CNG Ram Van to haul my cargo, the odyssey will be sold. At $1.69 a gallon, I'll go for extra cargo space.

And no sir, I'm technically not an engineer or mechanic. I run a route through western NC. I suppose what your title is and what you're good at are two different things.

[VxonFumes]

Thanks once again for the reply.

I figured since the idle air control valve bypasses air, the computer reads that in the exhaust stream and add more fuel. I thought it would act the same way as a vacuum leak that way. Whatever the case, it sure is annoying! I'll see if the new one helps. Give me details on your idle air control valve please...esp. what car did it come from? Also, mileage and price? I just purchased one from Majestic Honda though, it's been shipped but I have to pick it up and it's still unopened. The CX and VX have a different IACV than most Honda's, partly because those two models don't have fast idle valves, just a iacv. Most other similar Honda engines have both a iacv and a fast idle valve just under the throttle body, so on the VX the one valve performs double duty somehow.

the plugs had holes in the middle...so was guessing not used as magnetic drain bolts. How much does a descent fuel controller cost? I'm not too up to speed on them. Do you have to splice it into the wiring harness, or is there a more plug and play way to do it...this is OBD1 or zero, not sure which. I am a little nervous about altering fuel ratios though...there is a reason they richen ratios under load, although sometimes Honda does over-engineer things. It could compromise longevity if nothing else...unless you have extremely robust oil in there. Didn't you have an exhaust gas temp gauge? Did it alter the EG temps at all by leaning out the mixture while still under load (going up that mountain)? It should have.

I wasn't sure what I was talking about with divergent pipes either! I don't now which vehicle it was on...but there was a long pipe on the underside that wasn't the exhaust, but looked like another exhaust pipe that ended in what looked like a conical air filter??? I am still baffled by it.

Lastly, didn't mean to pry into your occupation or anything...you just seemed pretty handy so I took a guess. Don't know what I'm good at...got a master's degree that got me nowhere due to the "market," and am now in sales. On top of Amsoil, they also make really good natural fertilizers, but out here getting farmers to consider a more sustainable way to crop than just laying chemicals down is like going through a brick wall. So I guess what I do and what I am good at are sometimes different.

I'll take info on your idle air control valve if you don't mind. Is there a way to personal message me? Thanks again for your time.

[NachtRitter]

Originally Posted by VxonFumes

I wasn't sure what I was talking about with divergent pipes either! I don't now which vehicle it was on...but there was a long pipe on the underside that wasn't the exhaust, but looked like another exhaust pipe that ended in what looked like a conical air filter??? I am still baffled by it.

A picture is worth... a lot! I think you're talking about this one?

[Xist]

Originally Posted by NachtRitter

A picture is worth... a lot! I think you're talking about this one?

So... what is it?

[VxonFumes]

Thank you NachtRitter, that's the one. Perhaps Greasemonkee could offer prize money to the one who guesses correctly?

[slownugly]

crankcase evacuation?