[Car_Upgrade] Yet Another Mi16 1.9 Build

[Porter87 18]

looking good Andy! hope you get the issue sorted 

[Andy 105 1 Cars]

Engine not running and it stays connected. The rub is that up until Tuesday , engine running or not made no difference to its connection state . As for the noise on the WTS and throttle, the software allows one to display those voltage graphically in real time , so the occasional spike becomes clearly visible . Initially it was so bad the that fan would cut in and out rapidly once the water temp go close to 86 degrees. Now that has stabilised .

[jackherer 543]

It's not normally the first conclusion I'd jump to but I reckon Peter might be on to something when he says the ECU could be faulty. A dry joint perhaps that's opened up after moving the car about?

 

When you said earlier in the thread that your spark plugs were standard Mi16 NGKs are they resistor plugs? I don't know about other ECUs but Emeralds are very sensitive to non-resistor spark plugs and the standard Mi16 plug I believe is BCP7ET or BCP7ES which are non-resistor and which caused me all sorts of problems. I swapped for some with an 'R' in the part number and it fixed everything.

[welshpug 1,661]

bkr6ek was an Mi plug wasnt it?   or is that 2.0 and git6?

[jackherer 543]

I can only see bkr6ek listed for XU10J4, XU10J4R and XU10J2TE.

[Andy 105 1 Cars]

Bosch plugs now I have looked at them. They have an ‘r’ in the code . Thanks for that tip.The real bugger is that this is a new fault whereas the sensor voltage noises are historic . Hence Peters conclusion has a logic to,it, as reluctant as I am to jump to that conclusion. Tomorrow I plan to hook up the laptop inside the car and take the car out for a gentle drive , partly to see if the ‘long term trim’ function will begin to update the fuelling table in restricted regions of the fuelling map and partly  to see if I can replicate the disconnect fault .

All a bit frustrating . I could have chosen any number of other ECU manufacturers .With this one, I feel like a field development engineer.And all because I thought it would be a challenge not to stick with something I know (Emerald ) but to try something different .Hey ho.  

[petert 588]

All you’ve described points towards an issue with the ecu to me. I’d be on phone and asking for help.

 

Another thought however. Your ecu is grounding the ignition coils, yes? Perhaps that is where the source of the noise is coming from. I’ve never used an ecu that does that. Thus there’s always been an ignitor, cdi etc in between.

Edited October 10, 2019 by petert

[Andy 105 1 Cars]

Morning Peter,

 I keep coming back to that one. The ecu is grounding the coils. However, if I were running a coilpack and wasted spark, the ecu would, in effect , still be grounding the coils, but only two, whereas  mine is grounding 4 . One peculiarity of these S16 coils is that they are three pin coils, with the centre pin connected to ground. This must be one end of the secondary coil. I have grounded these, along with every other ground, to a single star earth point on the shell via my fuse box/ distribution board. It occurs to me that I have a large secondary loop . Perhaps I should ground the coils secondary directly to the block ( well, gearbox) so that the  HT loop is just plug-block-coil  to avoid the HT ground spike passing along the gearbox to shell earth strap .

 And if all that fails, back to Motorsport electronics with a ‘ please fix this ‘ request . 

[Tom Fenton 1,542]

Frustrating Andy, you should not be having these issues as I know you will have wired it up carefully.

[petert 588]

Cut the earths on the coils and see what happens!

 

If you were using ignition modules, there would be less chance of loop back to the ECU.

 

Tell me an OEM that grounds the coils directly to the ECU.

Edited October 11, 2019 by petert

[welshpug 1,661]

1 hour ago, petert said:

 

 

Tell me an OEM that grounds the coils directly to the ECU.

gti6?!

 

ignition power to one side via the double relay, other 4 trigger wires straight the ecu

[petert 588]

I thought they were like an LS coil and had an internal ignitor.

[Andy 105 1 Cars]

10 hours ago, petert said:

Cut the earths on the coils and see what happens!

 

If you were using ignition modules, there would be less chance of loop back to the ECU.

 

Tell me an OEM that grounds the coils directly to the ECU.

Cutting the earths puts the spark out. Thought  it would as the secondary coil no longer has continuity . As far as I can tell, most aftermarket ECUs have high current output stages so that they can directly ground so called ‘dumb coils’ . 

On a related topic Peter, I have tried and failed to find out the inductance of my coils , so cannot calculate the dwell time . At the moment I am using 2.6ms across all rpm and voltage ranges. Clearly I ought to increase that for low voltages . Does the Haltec haves dwell map or do the ignition amplifiers control and manage the dwell in your setup 

[petert 588]

None of the aftermarket ECU's I've had experience with can ground a normal coil directly.  Ignition modules (or igniters) can be classified as "dumb" or "intelligent/smart". Most ignition modules are dumb and include Bosch 124, 200, 211 etc, where you must set the dwell time in the ECU. Smart ignition modules include Bosch 008, 137, 139, which can automatically determine the dwell time for the coil being used.  Coils which have internal igniters, as fitted to most cars today, must still have the dwell set in the ECU. However, the trigger current is very low. eg TTL.

 

Yes, I'll find some dwell maps for you to consider. However, you should really put a CRO on a coil and determine the optimum dwell time. I would have though 2.6ms would be on the upper limit for COP.

 

Dwell tables for LS1/LS2 coils are well documented and usually take into account boost pressure and voltage. Typically you'd be at 3.5ms at cruise and up to 4.5ms at full boost, so the coil has time to cool.

 

I use a CDI, the input of which is 70/30 constant duty.

[petert 588]

Here you go. The default map from Autronic and a Haltech Nissan R32 map.

[Andy 105 1 Cars]

Thanks for the tables Peter. I spent some time last evening searching and found the Haltech and Autronic sites. Very helpful. You are right about trying to find the correct dwell time using a cro, hence my comment about wanting to know the inductance of the VE520169 coils I have , because that would allow me to calculate the correct dwell for various primary currents . However, that search proved to be fruitless so measurement would be the next step, especially as coils from different manufacturers or even related the same manufacturer( eg Bosch) stipulate quite different dwell times for their COP coils . Shame I am not using Honda K20 coils. Lots of info on those ! 

In the meantime. I have tracked these odd voltage fluctuations on the WTS and TPS signals back to the ecu itself . The supply voltage is rock solid at 4.95v, and for the TPS at tickover, my multimeter never flickered from 0.314v and yet on screen the same voltage was oscillating around 0.32-0.33v and then every few seconds dropping to 0.24v and back up to 0.32v .The guys at ME want me to log some data and some histograms which I will do , but it is looking very much like a software issue , which they think may be linked to the COP and the dwell time. Hmm. Not convinced but I will experiment 

[welshpug 1,661]

17 hours ago, petert said:

I thought they were like an LS coil and had an internal ignitor.

Ls coil is 4 wire single plug lead?  gti6 is only 2, my wasted spark 8v coil is 3 wire, power and 2 triggers to earth, running on dta s40, no amplifier/module.

Edited October 12, 2019 by welshpug

[petert 588]

12 hours ago, welshpug said:

Ls coil is 4 wire single plug lead?  gti6 is only 2, my wasted spark 8v coil is 3 wire, power and 2 triggers to earth, running on dta s40, no amplifier/module.

It seems to be a UK thing. Neither Motec, Autronic, Haltech or Wolf can fire a coil directly. All four need an ignition module or CDI.

 

You're asking the ECU to ground all the current from the coils and encouraging electrical interference to travel back along the grounding wires. Do you twist your wires to help eliminate interference?

Edited October 13, 2019 by petert

[Andy 105 1 Cars]

Yep. U.k thing. One of the reasons why the u.k ecu firms suggest twisted pairs for the TPS, WTS and ATS at the very least , if not screened cable, and screened of course for the cam and crank sensors . I did not use twisted pairs ( triplets) for my COP wires. I think I should have done, but I did route them quite carefully. Nevertheless, the switch to ground wire has to go to the ecu and yes, the ecu is switching up to 7 amps per coil, depending on the dwell time .One of the things I want to do is to reduce that current as much as I can for the reasons you suggest in your last post . 

I think that another factor here is that most of our U.K ECUs drive wasted  spark coil packs . They can drive COP but the manufactures seem to prefer their customers to use a coilpack. At least that is my experience with Emerald , DTA and Omex . 

[petert 588]

A wasted spark setup will be half the current. If it were mine, I still buy either a quad channel igniter or a four channel CDI, an get the spark away from the ECU.

 

[welshpug 1,661]

not an uk thing, Magnetti marelli did it on the gti6,  106 gti (another mm ecu)   no amlifiers on the v6 engine either, a Bosch ecu.

 

  I thought ignition amps were old school as I haven't seen any on a modern car in a long time.

[petert 588]

42 minutes ago, welshpug said:

I thought ignition amps were old school as I haven't seen any on a modern car in a long time.

Correct, because most COP's and coils have built in igniters and the ECU is only triggering/sinking a low current.

[SRDT 182]

Even the old Motronic ML4.1 could directly drive the coil, other manufacturers used it like that.

[Andy 105 1 Cars]

5 hours ago, petert said:

A wasted spark setup will be half the current. If it were mine, I still buy either a quad channel igniter or a four channel CDI, an get the spark away from the ECU.

 

Hi. I looked  hard at the quad channel igniter. The snag is that the coils then need to be mounted remotely with short HT leads. More modern coils with built in igniters, requiring only a 5v pulse from the ecu is probably the neatest solution. I would then simply have to make some kind of mounting bracket to 'locate the coils in the cam box cover. I am going to try to get my existing coils to work with this ecu . If I cannot , I will have to think again and start from scratch on the ignition system .

[Andy 105 1 Cars]

I am being stupid. A four channel igniter running my existing coils and converting the ecu to fire the igniter ( 5v trigger ) would do the job. The conversion is a check box in the software , so this might be the best option. I will try wit( the existing setup tomorrow , but if no joy, the above may be my best option.