Any MegaSquirt Gurus Here?

[jeffmsp]

I am no EMS wizard but I have used AFCs and several other devices in the past with great success. I am however a complete megasquirt NEWB, though I THINK I have a pretty good idea of how everything seems to opereate.


Right now I am trying to calibrate a MS unit I purchased from Lex for my BP swapped MSP.

I am looking to have my car professionally tuned by Lex at @ Stratified Auto in the next few weeks.

In the meantime I was hoping to get the car running as good as I can before I have him step in as it is expensive to have people tune the car so any problems I can eliminate myself means that he can spend more time tuning the car under boost/high load conditions.


Right now the problem I am having is with cold starting the car.

The stock map that came loaded on the MS unit is for 230cc injectors and the stock MS MAP sensor.

This tune was good enough to get the car started once I rescaled the fuel for 460cc but always bogged hard when I gave it throttle so I decided I should probably rescale the map for the 4bar MAP sensor to see if that works any better.

I ran a few numbers through excel and this is the scale I came up with for the 4bar. It is approximate but seems pretty decent. I get 99kpa readout from the MS software when I am not running the engine.

Now I am still having alot of issues getting the car started at times. It seems to have a mind of its own where on one occasion it will start first try, the next day I will be cranking til the battery is almost dead just to get it to catch. (never continuously in 5-8 second bursts of starter).

I am not sure if I am having problems because the scaling is incorrect or if it is because I have some other setting completely wrong.

With either the stock MAP sensor or the 4bar sensor MS Map I am getting violent backfires at times so I am not really interested in sticking my WB02 in the exhaust until I get it sorted a bit better. I also do not have a TPS wired in as Lex advised me that it is not necessary at this time.

I am currently pulling 16 VAC @ idle once the car is running which isnt terrible for ITBS but clearly they need to be syncronized a bit better.

Here are the settings I have in MegaSquirt.

I have tried changing the cold start values many times and what works one day seems completely irrelevant the next(20 degree increments? why such a big gap in increments in the software I dunno? a difference of 10 degrees in coolant temp seems to be enough to not have the car start sometimes if I was running it earlier), but below are some pics of the settings I usually start with and if its colder out.

Now for some reason, say I start the car, let it run for 10 mins, come back and turn it off and let it sit. Come back outside and go to start with coolant temp at say 55 degrees, no start. The settings that worked perfect at 40 degrees coolant temp are now completely useless for starting the car. So then I go and screw around with cold start values in the 40 degree cell and 60 degree cell, maybe if I am lucky the changes will be good enough to get it to start, otherwise I just leave them and let the car cool back down to 38-40 degrees coolant temp, go outside and it starts eventually.

I figured it might be because I am doing cold start based solely off coolant temp, so I tried using MAT temp only, and MAT/Coolant temp average. Still no dice.

 

[jeffmsp]

I also tried changing the injector staging from alternating to continuous but that too didnt make any changes to the way the car is acting.

When I am starting the car and it is struggling I am still reading 10-14 VAC as it tries to pull the RPMs up to running speed in the worst cylinder, so I dont think lack of vacuum is much of an issue.

I also have the o2 controller set to 0% because I have no 02 hooked up. I have tried changing the cranking RPM from 300 to 400 500 600 etc doesnt seem to make any difference in behaviour.

As I mentioned earlier I also have no TPS wired up, but when I go to real time display in MS it always says TPS is at 39% ? Not sure if there is a way to just turn it off altogether, but either way I have the bar dragged completely to MAP and 0% TPS on the Accel Wizard page so I dont think this is having an impact, just an oddity but who knows Ive never used MS before.

Any insight on my issues would be greatly appreciated and if anyone has a 4bar/460cc BP MS map lying around that they would not mind sending me please do!

Thanks! Jeff

 

[jeffmsp]

after another night of fun the car just wouldnt start last night. On a side note it turns out my block heater does work which is cool as it gets really cold when I go up north and FYI a stock BP block heater raises the coolant temperature to around 110 after being plugged in for a few hours.

in the end my battery was really crapping out and its really hard to tune cold start pulse widths with a drained battery sol i ended up playing with the settings and changing the cranking advance angle from 10 to 18, went back to alternating injection, changed all the cold start values and changed the overall required fuel. Left the car on the smart charger. We will see if it cures the issues with cold start when I go home tonight.

Good thing I have 2 cars or this would suck

 

[jeffmsp]

still acting flaky. starts sometimes, other times nothing. changed the priming pulse, changed the cold start values again, the after start values again, the cranking enrichment values and then got pissed off after charging my battery for the 100th time and went back to my base 2.5BAR 230cc map scaled for 460cc. Still flaky. Noticing I am occasionally having the unit reset during cranking now.

When the MS resets like this and then comes back online it continues to fire the coil even after I have stopped cranking the car which essentially will burn out the ignition system.(why it is grounding the ignitor in a fashion like its trying to run the car I have no idea, but once I manually turn off/on the MS it stops doing this immediately and goes back to normal.

So not having the MS reset randomly during starting is up on the list of things to do to protect my ignition system from certain death and to get the car starting running right.

Im guessing the working battery which is a few years old is having trouble during cranking, especially since it sat from August til January while I was gathering parts for the swap without being used, as the starter is drawing alot of power and the battery cant keep up, OR I am getting occasional dirty noise from the alternator. During 5-8 seconds of cranking the batt voltage is dropping as low as 9.5V so Im pretty sure its the battery and I guess the MS cannot compensate the pulsewidths properly, or maybe the MS can, I just dont know how to set this feature up in MS.

Next step is to swap the battery this weekend with one from my other car which is in good known working order and to unplug the alternator to see if the resetting keeps happening. If that doesnt work I am gonna throw in the lame ass 230cc injectors and see if it behaves any differently. Trial and error takes alot of time lol

Lots of views and no advice. If anyone knows a member who is a MS pro ask them to check out my thread.

And FYI Win7 and Vista are complete pieces of s*** when it comes to handling USB to COM adaptors, so buy a laptop with a proper COM port and throw your USB adaptor out the window if you plan to tune using MS.

When the car does start it is alot of fun to have a peppy little 1.8 booting around. I feel like I am 16 again driving and old escort gt lol but 127HP is pretty weaksauce so I dont think I could ever advise someone to swap this engine without a turbo as the low end torque is not sufficient in a heavy 3rd gen protege to enjoy your DD unless you are driving it like you stole it.

 

[jeffmsp]

well after another night of strange behavior I finally started thinking outside the box.

I pulled all 4 plugs and unhooked the ignition coil.

I got a small but bright flashlight and fired up the MS. I started turning over the engine and looked into each cylinder through the spark plug hole.

Its hard to see but if you turn over the engine enough times fuel from the injectors will start to become visible mist in the cylinders.

After watching a few times I noticed that the number 2 cylinder had hardly any fuel mist in the combustion chamber.

I pulled the injectors and put the suspected injector in the number 1 cylinder and repeated the test.

This verified the 1 injector was still spraying much less than the other 3.

Verdict: flaky injector.

I then pulled the 460cc injectors again and replaced with the weaksauce stock 230cc injectors. Reloaded the stock base map that has a rough 230cc calibration for an entirely stock motor(no itbs, full emissions, idle valve, VAF etc.)

Fired it up, started right away. Once the active start enrichment timed out the motor started chugging so I am clearly going to have to remap everything all over again for the 230cc.

Moral of the story, sometimes using cheap used parts found in online forum for sale threads is a false economy.


so...Anyone got a single rx7 460cc injector for sale ?

-Jeff

 

[racerx43269]

hell.. i couldnt even get mine to spark... so... i bought a haltech. lol
now both my mega squirts are going up for sale

 

[jeffmsp]

the ignition is pretty easy to troubleshoot. I had lex break it down for me when i was having intermittent spark issues.

wire from MS to ignitor. (ignitor must have a good ground)

then ignitor to negative side of coil. Make sure coil has 12V on positive side.

then coil plug to distribtutor

then distributor to plug wires

then wires to plugs.

were you getting rpm signal in your datalogs?

 

[racerx43269]

I am distributorless, running COP setup....
yes all the sensors and pickups work... fuel side worked fine... just no spark.. and rather then wait and try to get some one to answer a post... i just bought a haltech... i have been fiddling with it for a month..

 

[jeffmsp]

sounds like something wasnt hooked up right. I know MS can be a pain it really does take an investment of time to figure it out. Im pretty happy with it now though since mines going good now. Took a long time for a plug and play but it then end it was all my fault for using untested parts so I cant complain.

Next step AutoTune with MegaStudio. and then making some sweet custom gauges