Megasquirt arghgh
08-13-06, 08:15 PM
#53
MegaSquirt Mod
renns, I didn't set them to that, but will speak with James about getting them changed for future releases. I have never actually looked at the default settings because I always immediately load my msq after reflashing.
08-13-06, 09:59 PM
#54
Rotary Enthusiast
I took a look at Terrh's setup today, as he was in the area, braving a long drive with his relatively un-tuned setup. Here's what we found:
The AEM wideband has two different setup options in the settings.ini file. He had no documentation with him to determine which he had purchased, so we switched to the other AEM setting, and MS afr readings now match very closely to that on his digital display.
The car had a bad misfire problem above about 3500-4000 rpm, and was not drivable above that engine speed. Shortening the un-shielded portion of the VR harness down to a couple inches, and routing it as best as possible away from plug and alternator wires still resulted in the same problem. We dropped the staging point down to 2500 rpm, and the misfire problem stayed around 4k, so the secondary injectors and settings appeared to be working fine. As a test, we reversed the VR sensor leads at the CAS, and magically the problem was solved, resulting in clean accel all the way up through the rpm range. We had to re-adjust the CAS, as timing moved a fair bit with the reversed leads. Strangely, the final wiring connections are reversed to what's in the FAQ, with the CAS white wire serving as the MS tach in signal (+ve), and CAS red wire acting as CAS -ve.
We made a few tuning runs, got the un-boosted area of the map worked out to mid 13's afr, and he left for home. He's still got some work to do, but the car is running decent at this point. I'm sure it'll be a beast once it's fully tuned and spooling that big turbo to its full potential.
The AEM wideband has two different setup options in the settings.ini file. He had no documentation with him to determine which he had purchased, so we switched to the other AEM setting, and MS afr readings now match very closely to that on his digital display.
The car had a bad misfire problem above about 3500-4000 rpm, and was not drivable above that engine speed. Shortening the un-shielded portion of the VR harness down to a couple inches, and routing it as best as possible away from plug and alternator wires still resulted in the same problem. We dropped the staging point down to 2500 rpm, and the misfire problem stayed around 4k, so the secondary injectors and settings appeared to be working fine. As a test, we reversed the VR sensor leads at the CAS, and magically the problem was solved, resulting in clean accel all the way up through the rpm range. We had to re-adjust the CAS, as timing moved a fair bit with the reversed leads. Strangely, the final wiring connections are reversed to what's in the FAQ, with the CAS white wire serving as the MS tach in signal (+ve), and CAS red wire acting as CAS -ve.
We made a few tuning runs, got the un-boosted area of the map worked out to mid 13's afr, and he left for home. He's still got some work to do, but the car is running decent at this point. I'm sure it'll be a beast once it's fully tuned and spooling that big turbo to its full potential.
08-14-06, 12:09 AM
#55
MegaSquirt Mod
Ahh, I know what the problem is... if using the CAS wires backwards solves his problem, he has VROUT wired to TSEL instead of VROUTINV.
The ms1 chip triggers off the falling edge of the square wave from the conditioner, so it needs to be inverted to work correctly.
I'm absolutely sure that the FAQ is correct.... as I'm using a setup wired that way with TSEL wired to VROUTINV.
The ms1 chip triggers off the falling edge of the square wave from the conditioner, so it needs to be inverted to work correctly.
I'm absolutely sure that the FAQ is correct.... as I'm using a setup wired that way with TSEL wired to VROUTINV.
Last edited by muythaibxr; 08-14-06 at 12:11 AM.
08-14-06, 12:26 AM
#56
well, umm, yeah.
I guess roger summed it up there!
On the way home on the 401 the car seemed to have an intermittant misfire for no apprent reason - the AFR's seemed fine, revs were steady etc - I have no more signal noise - so I'm not sure why it was doing it. I switched to the GSL-SE timing map instead of 13bdarren's timing map (which resulted in crusiing at 15 degrees advance instead of 30) - and it still had the hesitation.
also (with both timing maps) - my turbo glows SUPER MEGA RED hot after cruising gently on the 401 (~85-90mph).
Any ideas on this one?
I guess roger summed it up there!
On the way home on the 401 the car seemed to have an intermittant misfire for no apprent reason - the AFR's seemed fine, revs were steady etc - I have no more signal noise - so I'm not sure why it was doing it. I switched to the GSL-SE timing map instead of 13bdarren's timing map (which resulted in crusiing at 15 degrees advance instead of 30) - and it still had the hesitation.
also (with both timing maps) - my turbo glows SUPER MEGA RED hot after cruising gently on the 401 (~85-90mph).
Any ideas on this one?
08-14-06, 12:32 AM
#57
MegaSquirt Mod
too much advance or too lean... maybe not enough split...
Less split causes more heat.
Also, check the inside of your MS, I'm almost willing to bet that you've got TSEL wired to VROUT instead of VROUTINV.
Less split causes more heat.
Also, check the inside of your MS, I'm almost willing to bet that you've got TSEL wired to VROUT instead of VROUTINV.
Last edited by muythaibxr; 08-14-06 at 12:35 AM.
08-14-06, 06:02 AM
#58
Rotary Enthusiast
Glad you made it back OK. Were you still seeing stable afr's at cruise? Did you datalog that drive back? Tapping the spacebar during logging will add a marker you can use to refer back to, which is helpful when looking for that random misfire.
A hot exhaust/glowing turbo is usually due to either heavy load, or retarded timing. Running retarded causes the fuel mixture to continue its combustion process in the turbo and exhaust rather than in the engine. What rpm/map were you running at? Seems odd that you see only 15 degrees in cruise. I'd expect you should have been around 3500 rpm/65 kPa or so at cruise on the highway, which results in about 25 degrees advance. Advance doesn't drop to 15 degrees until 140 kPa at that engine speed.
I bet Ken's right about that TSEL setting, although the documentation is not clear. The V3.0 build instructions simply say "Jumper TSEL to VROUT (Or VROUTINV if you want the VR input to be inverted)". From some other posts here, it sounds like this may be a common problem. Another useful detail to be added to the FAQ!
A hot exhaust/glowing turbo is usually due to either heavy load, or retarded timing. Running retarded causes the fuel mixture to continue its combustion process in the turbo and exhaust rather than in the engine. What rpm/map were you running at? Seems odd that you see only 15 degrees in cruise. I'd expect you should have been around 3500 rpm/65 kPa or so at cruise on the highway, which results in about 25 degrees advance. Advance doesn't drop to 15 degrees until 140 kPa at that engine speed.
I bet Ken's right about that TSEL setting, although the documentation is not clear. The V3.0 build instructions simply say "Jumper TSEL to VROUT (Or VROUTINV if you want the VR input to be inverted)". From some other posts here, it sounds like this may be a common problem. Another useful detail to be added to the FAQ!
08-14-06, 09:16 AM
#60
I was crusiing between 2750 and 3500 most of the way home... it resulted in 35-38 degrees timing in the one map and 16-20 in the other.. all that I noticed was that I had to use more gas pedal and got worse fuel milage once I went to the "16" map.
the MAP was 75-85kpa in the 16 map, I don't remember what it was in the other.
the map was as high as 110KPA to maintain speed when it was misfiring, which it did with both maps, though far more often with the more advanced one it seemed.
Both made the turbo glow.
the MAP was 75-85kpa in the 16 map, I don't remember what it was in the other.
the map was as high as 110KPA to maintain speed when it was misfiring, which it did with both maps, though far more often with the more advanced one it seemed.
Both made the turbo glow.