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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: Brian G on April 23, 2007, 03:48:10 pm
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im planning on putting a 1.9 tdi in self designed chassis for some racing. But I want to be able to do my own mapping of the engine. So I'm looking for a stand alone management system to run the 1.9 tdi. I heard it might be possible with MS and some add-on's. Anyone done anything like this before?
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yeah um megasquirt definetly will not work on a tdi
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just use the management system that originally came for the TDI and talk to redrotors. he is or was working on his own management system...
malone also does performance tuning on the ECU.
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At this point you are better off going all mechanical, although someone on the TDI-club had mentioned that they were running a 1.9TDI on a common-rail conversion and using stand-alone software. This was not in a car though, I think it is still being developed and running on a bench.
I think it was Kerma? I do not feel like going over there and searching right now. :P
Brendan
84 Scirocco 8v <-- TDI in progress
01 Jeep TJ 4.0
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I'll have a search for it. Im afraid I'll need to do it with the stock ECU and use the wire loom. Any thoughts on which loom/ecu has the least functions? which one would be the best to use?
I would love to run it with MS but thats a no-go at the moment. If only MS could do both the timing and the duration..... And having two MS work together is a no-go as well.
Would vagcom allow me to overwrite certain functions of the ecu/loom, for instance central locking, dashunit etc?
cheers for all your thoughts on this
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i don't think that the VE TDI will allow you to manipulate injection duration... unless you get a piezo injector...
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Yeah, you can disable a bunch of stuff in the ECU via the VAG-Com cable.
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this got me thinking yesterday, so I'm going to throw out some thoughts and questions,
I'm unsure of how stand-alone the OE ECM is, and what it requires from the engine to run, but maybe one could just use the factory ECM, but not the whole harness from the car? (assuming it's going into a mk1 or mk2, my application would be mk1 if I attempted an electronic control vs TDI-m)
The solenoid controlled VW pumps (I believe that's what the TDIs use, AHU/1Y, anyway) have a single solenoid to control injection events on all 4 cylinders. So only a single injector driver would be needed. Most of it is still mechanical like the IDI pumps, just that there's a solenoid to control the flow from the high pressure to the plunger to the injectors.
If one could hook a datalogger up to the solenoid, as well as find out crank angle, you may be able to find out what the injection event looks like based on crank angle and cam angle and stuff.
there's alot more questions in my head, but right now, I'm not so sure running a megasquirt is impossible if you can get injection event duration under control and running at the right part of the crank position, which can be roughly figured out with datalogging a running, OE TDI.
but it's not needed if the things the ECM needs are minimal and can be run without using the entire cars harness, and just a few external sensors, etc are needed.
I'm unsure of how integrated VW has made the ECM into the rest of the car, if it needs stupid things like if the ABS is working or not, or whatever, it won't work.
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this got me thinking yesterday, so I'm going to throw out some thoughts and questions,
I'm unsure of how stand-alone the OE ECM is, and what it requires from the engine to run, but maybe one could just use the factory ECM, but not the whole harness from the car? (assuming it's going into a mk1 or mk2, my application would be mk1 if I attempted an electronic control vs TDI-m)
That is what would commony be done.
The solenoid controlled VW pumps (I believe that's what the TDIs use, AHU/1Y, anyway)
electromechanical :wink:
oh, and it's 1Z :)
have a single solenoid to control injection events on all 4 cylinders. So only a single injector driver would be needed. Most of it is still mechanical like the IDI pumps, just that there's a solenoid to control the flow from the high pressure to the plunger to the injectors.
The quantity adjuster works much like the throttle linkage on a regular VE pump and just moves the control collar back and forth directly.
If one could hook a datalogger up to the solenoid, as well as find out crank angle, you may be able to find out what the injection event looks like based on crank angle and cam angle and stuff.
It looks like output voltage which increases to increase fuel. There is another solenoid which controls the dynamic advance.
there's alot more questions in my head, but right now, I'm not so sure running a megasquirt is impossible if you can get injection event duration under control and running at the right part of the crank position, which can be roughly figured out with datalogging a running, OE TDI.
I don't think you want a pulsed output so much as a linear one.
but it's not needed if the things the ECM needs are minimal and can be run without using the entire cars harness, and just a few external sensors, etc are needed.
What you're talking about is probably possible but the stock ecu really does an amazing job. Your standalone system would probably lose the smooth running idle control, as well as the automatic cold start advance, maf input, etc. Basically without just copying what the stock ecu does you end up with the electronic means to drive the pump....this begs the question of why not just go mechanical? I'm all for keeping it electronic but when you've removed that much function from it I hardly see the point in keeping it.
I'm unsure of how integrated VW has made the ECM into the rest of the car, if it needs stupid things like if the ABS is working or not, or whatever, it won't work.
The intrusion to other systems really can be minimal. The swap only has to be as complicated as you make it.
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thanks for the explanation, I also hadn't ever looking into how easy it'd be to swap in the electronics, and it's easy as hell, so screw standalone, not needed at all.
and I get 1Z and 2Y mixed up cause I was lookin at 2Y trannies. :oops: (not for the TDI, for my 4-door gasser)
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For the most part you can get whatever you need out of the stock management with programming. If you need programming work let me know since I'm close.
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wouldn't it be possible to program an ecu to make the electronic pump just run a program without sensors? it would theoretically be like running a mechanical pump... just the ecu connected directly to the pump... wayyy less wires!
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wouldn't it be possible to program an ecu to make the electronic pump just run a program without sensors? it would theoretically be like running a mechanical pump... just the ecu connected directly to the pump... wayyy less wires!
"Open loop" is what you're describing. It can be done but certain sensors are still going to be required. To control the position of the quantity adjuster, the servo loop must be closed by the quantity adjuster position sensor. To to control engine speed and simulate the operation of a mechanical governor, the crank position sensor will need to be used. To control timing there must be timing feedback from the #3 injector needle lift sensor. Fuel temperature, air temperature and engine temperature sensors aren't absolutely necessary to run the engine but they do provide the ability to adjust timing and injected quantity based on temperature in order to provide good cold starting/running capability. Mass air flow and intake air temperature provide boost enrichment capability, replacing the LDA on the mechanical pump. You might also want to keep those as well.
In reality, if you're going to use the stock loom, all that stuff is wired in there anyway, the only components that will need to be mounted are the mass air flow sensor, the boost pressure sensor (on later models) and the intake air temp sensor. Not much more work to have the complete system, probably easier than re-writing the ecm code to omit them.
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so a stand alone free programmable management such as with petrol engines is not possible at this time. The current SEM's cant control in the injectiontiming and injectionduration at the same time, combined in one signal. I was hoping some add-on's on MS would do the trick, but MS isn't that far yet. All the ECU providers here in Europe all give the same answer: no, its not posisble.
Wut im thinking now is to get a 110 bhp setup. I can get a early Audi A4 with this 110 setup, from which i can get the complete wiringloom, engine, ECU, dash, and all the rest that is connected to the ECU. Than I can have the comp reset and have a lot of those signals overwritten. And with some fashing I can get the map in I want. With the right signals overwritten, i can take out that bit of the loom, cos its a waste of weight and I don't quite have the space in this new car im gonna build. All the wiring of the lights, indicators and horn will be run seperate anyway.
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i would like to ask how injection duration can be adjusted on the TDI's?
are we talking about injectors that are opened electrically? I just can't see how injection duration can be manipulated with injectors that open at a certain pressure...
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TDIs that use the VE pump still have mechanical injectors. The only thing the solenoid does is control how much fuel gets into each line by a solenoid controlling the flow from the pressure side of the pump to the pump head/rotor, which is what bumps it up to the super high pressure to the injectors.
there's a single solenoid controlling the flow to all 4 injectors.
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The quantity adjuster is a servo which moves the control collar. The control collar is what covers the spill ports on the plunger. With the spill ports covered the fuel pressure cannot bleed off back into the pump housing and isntead the pressure heading to the injectors will rise further. The increased pressure and fuel volume will extend the injector duration until pressure in the line drops back below the opening pressure of the injector.
The quantity adjuster can make small adjustments to regulate fuel on a cylinder by cylinder basis. This is how the ecu adjusts for injector variances and smooths the idle.
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The cummins 24v bosch VP44 pump can control timming and it has mech. injectors. There is a very fast acting solenoid that opens and closes when each cylinder is to be fired. I don't know the exact details but they do it.
Seems like it would be easier to make a common rail system with 4 individualy controlled injectors.
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yeah you can't control duration (with vp37), only advance.
duration is fixed to the combination pumpcam/plunger/injector(pressure and size)