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No problems was just asumming that the injectors where at the end of there duty cycle and I should jump to 550cc. So then I had issues with the car running correctly with the 550's so put the stockers back in to test it and make sure it wasn't something with the engine and decided to really see where the stock injectors where pulse wise. Just put the 550's back in and got a brand new tune and now my computer that I use will not turn on !! This suck's !
Old post but same issue after checking a year later. Running 550 injectors and 28-30 IDC and that puts me at 140% - 150% duty cycle again when doing the math.
Clearly the injector can only go 100% but the math shows I am way over that after 3,500-4,000 rpm. There hs to be something off with the ECU and gauge interpretation no ???
I have no idea what the horsepower is but find it hard to believe I am over 550 to the wheels. 17lbs boost and full exhaust. https://fuelinjectorclinic.com/flow-calculator
Old post but same issue after checking a year later. Running 550 injectors and 28-30 IDC and that puts me at 140% - 150% duty cycle again when doing the math.
Clearly the injector can only go 100% but the math shows I am way over that after 3,500-4,000 rpm. There hs to be something off with the ECU and gauge interpretation no ???
I have no idea what the horsepower is but find it hard to believe I am over 550 to the wheels. 17lbs boost and full exhaust. https://fuelinjectorclinic.com/flow-calculator
I have an Innovate SSI-4 that logs injector duty cycle so direct log not OBD2. In the top of second I am at 95% duty cycle and drop 10 lbs of fuel pressure. I run about 14 lbs of boost depending on ambient. This is with stock exhaust and manifolds, stock injectors, stock HE, 82mm TB, and 77mm FSP.
AFR stays fairly consistent and goes slightly richer at the end of the pull. I will not be doing anymore full pulls until I get injectors as I do not want to lose one!
Here is my post from Facebook with graph:
Data post. Got all channels working and finally downloaded one of my runs from the end of December.
This was in 60 degree ambient with a little heat soak starting the run.Colors are from top to bottom:
Black - Time
Pink - Meth Pump PSI
Black - Injector Duty Cycle
Green - Bypass Valve Position (100% is closed)
Blue - AFR
Orange - RPM
Red - MB IAT Sensor Temp
Olive - MB MAP Sensor (Boost)
Purple - MB TPS Sensor (100% is open)
Brown - Fuel Pressure (Aftermarket Sensor)
Green - OBD2 Timing Advance .
Some things I noticed:With an 82mm TB and 77mm FSP I am now out of injector. IDC is 93.7% in top of second gear, I would expect it to get worse in higher gear. Car still holds commanded AFR (as well as the ecu can anyway). At 60 ambient the meth system is working great keeping temp rise to 2 degrees F over starting temp. This is with a factory HE and an engine bay tank, 33% coolant to distilled water mix.
You can see the bypass valve is not just open and close but follows the throttle somewhat.
Boost was good at 13.35 psi max at sea level conditions in second, would be higher in upper gears. Meth pump working strong! But activation takes a little time. From activation (6psi) it takes a split second to activate and I am already at 10 psi. Really need to get a controller.
Tune working great as timing is at -20.5 degrees. I lose 9 psi of fuel pressure during the run but it recovers quickly.
Mods to car:2004 E55 AMG 109k miles. Meth system, #3 post TB nozzle and #10 post IC nozzle with a boost switch. 82mm TM. 77mm FSP. Engine bay tank. Bosch 010 pump. RaceIQ tune. Innovate LM2 data logger with SSI-4 expansion module giving 10 channels of analog data plus OBD2 data (only log timing on OBD2). Everything else is stock.
So here I am now with new 60lb injectors, 11.2 afr and 27 idc.
This is making no sense to me.
Seanol how is your IDC calculated. My car will be a 2.08 at idle and go to 27 at boost and this calculates to over 100% yet again !! I have to be missinterpeting this reading wrong because I can not see 60lb injectors going static in my engine !!!
Innovate reads it off of the injector directly. The formula I have seen is RPM x Injector Pulse Width / 1200.
That would make your reading at idle (Assuming 700 rpm) 2.08 x 700 / 1200 or 1.21%. 27ms seems awfully high. At 6500 you would be at 145% which is not right.
What RPM are you getting 27ms on time? You are reading the negative, right? I am guessing so as otherwise you would get no reading.
If you halve the rpm (3250) you get 73% which is more reasonable. Could the RPM signal have an issue?
How many PID's are you logging? OBD2 sampling rate is bad on this ECU and the more PID's you log the worse it gets. Have you tried just sampling IDC? May or may not help. I did a quick search but found little on the mercedes IDC pid so not sure how accurate it may be or how it is calculated.
I went analog sampling as OBD2 info was so delayed. Only OBD2 pid I sample is timing.
Just the pid. I am going to crank up fuel pressure and reduce idc a little in the tune and see where it leaves me with the AFR
Seanol do you need a set of 550cc's? I have them if you do.
01-15-2018, 09:19 PM
