MPGs run, Aspire SE

[rmoltis]

The factory idle specification is between 650-750rpms at idle for manual
fully warmed up which is set at 195-200* coolant temp.

[TominMO]

Went on another run today. FP @ 36, cam @ 0, timing 13 BTDC, vac 22. Threw a code 17 about 12 miles into the test, then started running rich. Aborted test, returned home, set FP to 42 and cleared code. I was surprised it threw the code, since I have a heated O2 sensor. If it throws it again at FP 42, I will try using the data wire from the wideband instead of the heated narrowband.

Will try again possibly tmw, more likely Monday.

It's still stalling out when coming down to idle, unless I take it out of gear when it's down to about 1000 RPM already. I tightened the throttle cable (I normally keep some slack in it) so it can't go below 800 RPM. We'll see if that helps. I can't use the idle speed adjustment screw, because it already does idle at a steady 800 RPM.

[TominMO]

seeing a closed loop idle A/F ratio in the 12s is no good. that needs to be addressed, but the main thing to focus on NOW is the cruise A/F (most of your time is spent moving, not idling). so at least you have a solid vacuum signal to start with. and also keep in mind that the A/F gauge is a tuning AID, not a "must have x-A/F" type of thing.
make sure the heater element of the MAF is clean and not corroded/missing material: that can lead to a false signal.

I'll check the MAF element. Tmw morning I will check cruising AFR, and adjust the FP as needed; probably down to 36, because I want to see what can be done with stock pressure, so that someone could just buy the cam. Kinda feel like I'm starting over; maybe all my tests were with poor vacuum!

[FestYboy]

seeing a closed loop idle A/F ratio in the 12s is no good. that needs to be addressed, but the main thing to focus on NOW is the cruise A/F (most of your time is spent moving, not idling). so at least you have a solid vacuum signal to start with. and also keep in mind that the A/F gauge is a tuning AID, not a "must have x-A/F" type of thing.
make sure the heater element of the MAF is clean and not corroded/missing material: that can lead to a false signal.

[getnpsi]

I had some chitchat with zanzer in pms before madness. My next brainstorm was to use driver actated extra egr operated only by relay via the 5th gear switch. This way normal driving is stock and less burnable mixture needed on highway at low loading

[TominMO]

This is where I wish I had a better knowledge of JTAG to interface ICs...... You've found the limits mechanically, now we need to fully remap tables @ the binary level!

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

Even on the Megasquirt website, they are not too promising about getting better mileage. Really might need a smaller-displacement motor, different gearing, and/or less weight to start making a difference.

Edit: Might play with fuel pressure a bit more tho. We'll see how this next run goes.

[jason_]

This is where I wish I had a better knowledge of JTAG to interface ICs...... You've found the limits mechanically, now we need to fully remap tables @ the binary level!

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

[TominMO]

Today I stuck the OEM cam pulley back on, thereby eliminating the dreaded woka-woka sound. As I half-suspected, the broken set screw was the issue. Simple to replace. Thank John it wasn't the water pump. Runs nice and quiet now.

Had to re-time the motor since the cam pulley brought cam timing back to 0. Using the jumpers, vac gauge and timing light, I ended up with 13 degrees BTDC and 22" of vacuum. The wideband gauge was reading an AFR of ~12 when warmed up. I will go on a last run, possibly tmw, but am not expecting miracles anymore. I think it's just too hard to defeat the ECU by simple mechanical parts changes. If I don't get results that convince me to keep the MPG cam in (like 55 MPG), I will swap the OEM cam back in, and at least I will have a little better breathing to make use of the header.

[TominMO]

No drive today. Gotta do other stuff, plus too cold (for me--43 and very windy) to work on car for a couple of hours. My issue might not be the water pump, it might be the aftermarket cam gear. One of the five screws it uses to hold the adjustment broke off a week ago (it seemed cross-threaded, hard to turn, tho I had never removed it). Seemed to hold fine with four, but the woka-woka sound might be from that one screw not being there, i.e., it's slightly skewed. Gonna change back to the OEM cam gear, since 0 degrees is the center of the sweet spot, replace the broken screw and use it on something else in the future. Hopefully that is the noise issue and I don't also have to replace the WP. But not today, too cold. Tmw afternoon, then a drive over the weekend.

[TominMO]

for your purposes, absolutely Tom.

OK thanks. That may well be the end of my MPG tuning (I might go to 0 cam timing just to be in the middle of the sweet spot). I'll go on a run tmw unless my local expert thinks the WP might not make it.

[FestYboy]

for your purposes, absolutely Tom.

[TominMO]

So Arty, you're saying the way I did it is OK?

BTW I think it's my water pump that's making the noise. Bearing failure = woka woka noise? I replaced the timing belt when I got the car two years ago, but decided to not do the pump, and it lasted this long.

[FestYboy]

^ ummm why not? when you jumper the ECU, your eliminate it's control and are able to set base ignition BEFORE the ecu is able to run it's timing tables. when you restart the engine , the ECU assumes the physical timing is set to spec (it doesn't know if it's advanced or retarded) and runs it's tables as if everything is normal.

Tom, now you can see that if you had used a less accurate tool (the boost/vac gauge), it would have driven you mad trying to get acceptable vacuum. accurate information is key.
BTW, how are your plugs looking?

[getnpsi]

No you cant adjust idle trying to get best vacuum with no ecu once its on, idle and advance comes up which should pull more but thats based on valve events

[TominMO]

No you want to have ecu contolling idle timing but it will be close like that

?? Are you saying I should adjust ignition without the jumper, or with?

@ Arty: I hooked up my combo boost/vac gauge to see how accurate it was. When the HF gauge read 21", the combo gauge read 16.