Microtech Area is for discussing Microtech systems

Aux input correct use

Old 01-19-17, 11:21 AM
  #1  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
Aux input correct use

Just a thought.. But do the enrichment and timing corrections under aux input only come into play when the car is at idle or will they add across the map? Just a thought as I would imagine you only want these to occur at idle especially if you are using any timing correction? If only idle then I presume it rely's on tps to detect this which as I know the TPS are not super reliable? Basically I am working on a small circuit I can connect to the input which will detect any voltage drops due to electrical loads being switched on and then allow you to use the input Aux to correct idle to suit. If as I believe we only want this to work at idle then I am toying with having microswitch on the throttle to detect throttle off position in place of the unreliable TPS?
Alternatively if people think the correction should be map wide if the voltage has dropped off I might need to rethink that.. Chances are though when you apply throttle the alternator will push the voltage back up and have no need for corrections?
I plan to have a time delay in the aux input switching off after the voltage stabilises to try and keep things a bit smooth too. Maybe it won't need that and it just needs to be on/off?
Once your fans kick in the voltage seems to stabilise after a few seconds so it seems no point in keeping an additional correction for timing or rpm if the engine is running in a steady state?
Would appreciate a bit of input. If it works I might get a few made if people are interested.

Cheers
Lee
Leeroy_25 is offline  
Old 01-21-17, 10:15 AM
  #2  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
Far as I know they apply across the map.

Keep in mind that if you use something connected to the aux input to increase timing, say your fan signal, that timing increase will apply always even under boost. Bad.

You're starting to think about working around the Microtech's limitations. Every other ECU on the planet can compensate for electrical loads.

There is "FanAdd" feature on the Microtech though that can add a little fuel when the fans are switched on. In my experience it only somewhat helps because the engine doesn't just want fuel, it wants a little more air. In fact I wish the FanAdd would accept negative numbers because in my case (bridgeported engines are a little funky) it would run better under that light load with a little les fuel.
Aaron Cake is offline  
Old 01-21-17, 03:24 PM
  #3  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
Thanks for info. I thought it would be across the board, but thought I would check incase my throttle switch was not needed. Out of idle I think applied loads would be far less of an issue anyway? And it was timing I was most concerned about. Going to order the bits for my work around later. Will let you know when it's hooked up!
Leeroy_25 is offline  
Old 01-28-17, 10:13 AM
  #4  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
Just be aware of the feature if you add timing, which would help stabilise the idle under the load of the fan. That gets applied across the entire load curve so if the fan is on, you could find yourself adding a few degrees of timing under boost.

I've stayed away from those settings for that reason. Found on my own car adding fuel absolutely didn't help. The engine responded to more timing and a bit less fuel. But then I saw on the dyno (because I had the terrible datalogger open) that those changes were applied while I was making runs under boost! Sort of a shock to see the ECU running timing at 18 degrees while you are scratching your head thinking "Why isn't it 15?!".
Aaron Cake is offline  
Old 01-29-17, 02:35 PM
  #5  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
Thanks Arron,
I figured the timing setting could be a bit dangerous.. That is why I want to run a microswitch to detect throttle closed so it can only make the corrections during idle. i would use the TPS sensor for that but being how unreliable it is I think opting for a simple stand alone microswitch is no big deal.. i cannot see that you would ever need these corrections at any time other than idle? Surely once the engine is doing more than a 1000rpm or so the alternator will be putting out way more juice than you need and hence you shouldn't see nay voltage fluctuations as loads come on.. or certainly if you did they would be for a split second..
I do hear your comments about the ECU. However I have a couple of reasons for pushing on with what I have..
First, I don't give in easy! And now I have an option to make a simple improvement with a little plug in box for a few quid I am intrigued to see if it will work. Also I really want the car on the road for spring/summer this year. I won't have time to rewire, and set-up a new ecu to do this I don't think. I need a tune on the car before I pull the engine to rebuild over winter. Which is booked in for 3 weeks time. I am already behind schedule as that should have been getting done next week!
Tuner is going into matrix mode and said the reason he wasn't going to was to get a quick base tune to serve the purpose of setting up from when it has a full tune with the new engine. We are just going to go straight into it now though which he agree retrospectively is probably a better plan.
The car is only going to be a weekend toy so if I have a bit of compromise I am not too worried. I want it to be drive-able of course though and not cause any issues as a result. I am sure I can manage that with the microtech!? I hope!!
I will probably only keep the car a max of 2 years then I will be itching to build something else. So if after 1st year I think the ECU is pants and has too many issues I will look at swapping it out next winter assuming i have no other issues to resolve by then!

Hopefully that all sounds pretty sane?! There is usually a method to my madness!
Leeroy_25 is offline  
Old 02-04-17, 10:29 AM
  #6  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
But remember that until the ECU is fully tuned, attempting to correct idle fluctuations with external hardware should be approached with caution.

A lot of idle stabilization can be achieved by making the idle are of the fuel table look like a valley. Tune the fuel bin that the engine idles in a tiny bit on the lean side, or just right for the engine to idle at that time (no electrical load). Then the surrounding bins get tuned slightly richer. This has the effect of catching the idle if it starts to wander. The low resolution of the Microtech makes this less of an option without compromising the surrounding area of the fuel map, but it can still work.

Unfortunately the 2nd part of this is to perform the same thing on the timing table. But since the Microtech doesn't have a timing table, the best you can do is use a combination of the T_MAP and T_RPM table around the idle area to form that valley.

On a non complicated install without huge electrical loads, often this is all that is needed to obtain a reasonably stable idle.
Aaron Cake is offline  
Old 02-04-17, 05:27 PM
  #7  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
Thanks Aaron,
I will keep that in mind.. Sounds logical and now I have seen matrix mode an easy approach to play with. I kind of tried this in carb mode but the idle pretty much stuck to the one cell in the idle chart. or until it was too late anyway. with my better idle after setting up today I hope I can avoid running an aux input. and maybe even idle control valve.. Although it would be a nice bonus if I could get it to work. If not I might change the output to a fan trigger.
Leeroy_25 is offline  
Old 02-05-17, 09:47 AM
  #8  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
Been using the Microtech fan trigger, but it kind of sucks. It has a limited use range. You can tell it when to turn the fan on, but the off point is always set something like 4 or 5 degrees under that temp. In my case it means having the on point set to 92 degrees otherwise the off point is too low and the fan runs continuously as the off point ends up below thermostat temp. 92 degrees is rather annoying because it causes the temp gauge to wag up and down. Other ECUs allow an off point to be set.
Aaron Cake is offline  
Old 02-07-17, 02:20 PM
  #9  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
Where do you find the car tends to run temp wise or would it run hotter if you had a higher trigger on the fan? I think maybe a lower temp fan switch is the easy answer then if the ECU trigger is not all that? As I recall a turbo II one is about 90 or 92degC and fits the same as the FD style one. Just cannot find one for love nor money over here!
Leeroy_25 is offline  
Old 02-11-17, 10:36 AM
  #10  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
I'd have to look at my ECU to see how I have the fan configured. From memory, I have to have my fan set to 92 degrees (I think the Microtech only allows moving the trigger point in 2 degree increments). Which is not damaging temperature at all, but it is about halfway on the S4 temperature gauge. So I'm always seeing the gauge wag up and down in traffic. If I set it lower, the hard coded off point on the Microtech is below thermostat temp (86 degrees I think on the FC?) so the fan basically never shuts off, or rarely does, once the car has warmed up.

I'd much rather have the fan configured to turn on at 90 degrees, and off at 87 degrees. On my Cosmo I've gone to a two stage fan. One will trigger on at 88 and off at 87 or 86, then another will trigger at 90 and off at 87/86 (or run if the A/C is on). But the ECU allows that configuration.

If you want better fan control, most of the fan manufacturers sell a controller.

Or it could be your first electronics project with an Arduino! ATTINY85 could easily do it with minimal support circuitry and 20 lines of code.
Aaron Cake is offline  
Old 02-12-17, 08:46 AM
  #11  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
I think I will play around with fan switches before I use the ECU as a fan trigger. I have an aftermarket Thermostat too. One of the Tridon racing ones. Cannot remember the temp on it off hand.
Leeroy_25 is offline  
Old 02-12-17, 09:53 AM
  #12  
Engine, Not Motor
iTrader: (1)
 
Aaron Cake's Avatar
 
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,671
Likes: 0
Received 23 Likes on 22 Posts
Make sure that your thermostat temp is above the Microtech warmup map cutoff. On other ECUs you can adjust the warmup map temp points, on the Microtech you cannot. If your thermostat is below that temp you will always be in the warmup correction map.
Aaron Cake is offline  
Old 02-12-17, 03:28 PM
  #13  
Rotary Enthusiast
Thread Starter
 
Join Date: Aug 2008
Location: Portsmouth UK
Posts: 1,101
Received 13 Likes on 13 Posts
I don't seem to have any issues with it warming up so I don't think that will be an issue. if anything it runs a bit warm for my liking but then I have had it standing in the garage or on a dyno! So we will see when it hits the road. i think it will run in the 90-95degC range as a hunch. It is a Tridon Hi Flow stat anyhow and the temp is 82DegsC I just looked it up.
Thanks for info though.
Leeroy_25 is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: