Need MaxxECU base tune
General best practice is to get your base idle fuel and timing right with it in a fixed position (set your idle screw) when the car warmed up. Then tune it open loop/setup your warmup map/compensations and then move onto closed if you need to.
Posting on the other MaxxECU thread, but thought I’d update this one that I started.
After getting sync errors when revving, I went ahead and installed the 36-1 wheel and VR sensor I purchased. Setup was very straightforward and dare I say easy. I then built my first harness wire using shielded wire, heat shrink, and heat wrap. I learned that I could connect it to the stock Speed sensor plug on the stock harness. Keep in mind I’m still using the adapter harness I purchased with the MaxxECU. Again pretty straightforward.
I purchased a timing light gun and set my timing.
The car is now idling very well. I can rev and I’m not getting any sync errors. Mission accomplished. I admit that I might be making this up in my head but the engine seems to be idling so much better compared to the stock ECU and A-tune chip. It’s almost purring, and that’s with my first attempt. I’m sure I can fiddle with it more to get the timing perfect. But very happy so far.
One note I will mention. I’ve read many comments about the stock sensors not being shielded which is why it’s claimed they don’t work well with a standalone. But I’ve learned that they are in fact shielded. Which is why they have 3 pins in the connectors. Note that I’m using the stock harness connector and the stock male connector which I cut from a stock sensor and spliced to my wire.
The only question I have is does the stock shielded wire go to an appropriate shielding wire ground. I don’t think it does and I have no idea if that matters or not. But the MaxxECU has a dedicated ground AND a dedicated shield wire ground. Meaning they terminate at different pins. Instructions make it clear to only use shield ground for the shield wire.
I’ve also read that most standalones have trouble reading the stock starter ring because to many teeth. So maybe it’s not an issue with shielding. My guess is that sensor gap matters a lot more. Maybe I could have gotten it to work with the stock sensors if I adjusted the gap. So maybe this explains why some folks have no problem using stock trigger setup. I will admit I never paid to much attention to the sensor gap.
All that being said, I would suggest just biting the bullet and going with a 36-1 setup. The trigger wheel setup I purchased was about $300 and a very elegant solution. Included the VR sensor and shipping. The wheel already welded to pulley. Probably the easiest thing I’ve installed on my car. A no brainer in my mind.
Time is limited but hopefully I can get the car driving in the next couple of weeks. Still reading up on the self tuning features. I’m having fun learning.
After getting sync errors when revving, I went ahead and installed the 36-1 wheel and VR sensor I purchased. Setup was very straightforward and dare I say easy. I then built my first harness wire using shielded wire, heat shrink, and heat wrap. I learned that I could connect it to the stock Speed sensor plug on the stock harness. Keep in mind I’m still using the adapter harness I purchased with the MaxxECU. Again pretty straightforward.
I purchased a timing light gun and set my timing.
The car is now idling very well. I can rev and I’m not getting any sync errors. Mission accomplished. I admit that I might be making this up in my head but the engine seems to be idling so much better compared to the stock ECU and A-tune chip. It’s almost purring, and that’s with my first attempt. I’m sure I can fiddle with it more to get the timing perfect. But very happy so far.
One note I will mention. I’ve read many comments about the stock sensors not being shielded which is why it’s claimed they don’t work well with a standalone. But I’ve learned that they are in fact shielded. Which is why they have 3 pins in the connectors. Note that I’m using the stock harness connector and the stock male connector which I cut from a stock sensor and spliced to my wire.
The only question I have is does the stock shielded wire go to an appropriate shielding wire ground. I don’t think it does and I have no idea if that matters or not. But the MaxxECU has a dedicated ground AND a dedicated shield wire ground. Meaning they terminate at different pins. Instructions make it clear to only use shield ground for the shield wire.
I’ve also read that most standalones have trouble reading the stock starter ring because to many teeth. So maybe it’s not an issue with shielding. My guess is that sensor gap matters a lot more. Maybe I could have gotten it to work with the stock sensors if I adjusted the gap. So maybe this explains why some folks have no problem using stock trigger setup. I will admit I never paid to much attention to the sensor gap.
All that being said, I would suggest just biting the bullet and going with a 36-1 setup. The trigger wheel setup I purchased was about $300 and a very elegant solution. Included the VR sensor and shipping. The wheel already welded to pulley. Probably the easiest thing I’ve installed on my car. A no brainer in my mind.
Time is limited but hopefully I can get the car driving in the next couple of weeks. Still reading up on the self tuning features. I’m having fun learning.
Used some reflective tape to draw my timing marks. Made it really easy to use my timing gun to triple check the timing. Glad I got a variable light gun, it allowed me to lock the timing on the ECU and then verify the timing by adjusting the gun to the same setting.
Then finally took the car out for a drive. I kept it out of boost, just some light cruising. Car felt great. Could be my imagination but it even felt like more torque down low with no boost. I did have an occasional pop during deceleration and a stall in first gear, so I know I have a lot tuning to do.
My next goal is to configure the electronic boost controller. Still a lot to learn and configure but I can see the light at the end of the tunnel.
Then finally took the car out for a drive. I kept it out of boost, just some light cruising. Car felt great. Could be my imagination but it even felt like more torque down low with no boost. I did have an occasional pop during deceleration and a stall in first gear, so I know I have a lot tuning to do.
My next goal is to configure the electronic boost controller. Still a lot to learn and configure but I can see the light at the end of the tunnel.
Continuing to make progress. Car already “feels” better than stock, which is pretty cool. Obviously this being my first standalone and learning it from complete scratch, I must say the MaxxECU has been awesome. Very intuitive to learn, though you do have to make the effort to study, but once you do it all starts to make sense. I’ve even set boost limits, which I’ve already hit so I know they are working.
I mean, I went from not knowing how to set my TDC timing let alone really understanding what advancing timing really meant. To now playing with my injector dead time.
The car felt like it was running well, but felt like my warm idle AFR was still to rich at about 12. Kept playing with VE and timing but nothing really worked. Then came across injector dead time. After some reading I realized I was using a Nissan Quest alternator, which gives higher voltage than stock at about 13.5v per the ECU reading. This in turn opens the injectors faster. (I think).
My setting is 1.6ms with Deka 80s, which seems to high and “might” be why my AFR is a little rich. Will be playing with changing it this evening. But thought I’d ask what folks have for this setting?
I mean, I went from not knowing how to set my TDC timing let alone really understanding what advancing timing really meant. To now playing with my injector dead time.
The car felt like it was running well, but felt like my warm idle AFR was still to rich at about 12. Kept playing with VE and timing but nothing really worked. Then came across injector dead time. After some reading I realized I was using a Nissan Quest alternator, which gives higher voltage than stock at about 13.5v per the ECU reading. This in turn opens the injectors faster. (I think).
My setting is 1.6ms with Deka 80s, which seems to high and “might” be why my AFR is a little rich. Will be playing with changing it this evening. But thought I’d ask what folks have for this setting?
Most injector manufacturers provide a dead time table for a certain fuel pressure with values to compensate for voltage. You'll need to find this data and properly configure you injectors before you go to much further with tuning.
Fancier injectors have a characterization table to compensate for non-linear flow, especially at the lower end. This can really help with idle with big injectors.
Fancier injectors have a characterization table to compensate for non-linear flow, especially at the lower end. This can really help with idle with big injectors.
I’ve found several posts mentioning that folks can’t seem to find this information for Siemens Deka 80lb injectors. I’ll keep researching.
I have found a few ways to calculate it. Still trying to wrap my head around it though. But from what I’ve surmised so far, you can just adjust the settings and see what happens to AFR.
I have found a few ways to calculate it. Still trying to wrap my head around it though. But from what I’ve surmised so far, you can just adjust the settings and see what happens to AFR.
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blueline
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Ok - this is an AI answer, so take it with several huge grains of salt. Having said that, maybe it will offer some worthwhile info and/or leads.
https://www.perplexity.ai/search/where- ... kQJPdBc1lw
https://www.perplexity.ai/search/where- ... kQJPdBc1lw
Tim
Current:
'26 911 Carrera S - PTS Verde British Racing Green
'24 Cayenne S - Algarve Blue Metallic
'21 718 Cayman GTS - Black
'22 911 Turbo S - Carmine Red
'21 718 Cayman GT4 - White
'11 GMC 1500 Quad Cab 4x4 - Black
Musik-Stadt Region
Current:
'26 911 Carrera S - PTS Verde British Racing Green
'24 Cayenne S - Algarve Blue Metallic
'21 718 Cayman GTS - Black
'22 911 Turbo S - Carmine Red
'21 718 Cayman GT4 - White
'11 GMC 1500 Quad Cab 4x4 - Black
Musik-Stadt Region
I saw a post somewhere that said Ford Motorsport rebadge the deka injectors and have a datasheet but I didn't follow it up.944m3 wrote: Sun Jul 06, 2025 7:44 pm I’ve found several posts mentioning that folks can’t seem to find this information for Siemens Deka 80lb injectors. I’ll keep researching.
I have found a few ways to calculate it. Still trying to wrap my head around it though. But from what I’ve surmised so far, you can just adjust the settings and see what happens to AFR.
This is the exact reason why I paid more for Injector Dynamics, even a lot of the other modified Bosch injectors don't have great data