Following getting the blackbird engine fired up on megasquirt (with manual fuel pump bypass) its not time to turn my attention to why the ECU is not
firing the fuel pump.
Took the ECU out of the car and hooked up the stimulator and the laptop but no fuel pump LED on the stim (everything else seams to work....
I'm pretty sure the fuel pump LED originally lit up when i bench tested the ECU after i built it, the only thing that has changed is i have
loaded up a map donated by a similar install.
Before i dump the map and go back to 'factory settings' to test it, is there anywhere in megatune or the .ini file where i can 'turn
the fuel pump off/on'?
Also whats the best way to return the ECU to 'factory settings'?
Ash
fairly sure a firmware re flash goes back to the std image (IIRC was for an 8 cylinder engine not running EDIS) so will need going through and setting
up afterwards thoroughly before trying to get her running
Myself and a couple of others on here have had the fuel pump transistor die prematurely (this is on V2.2 hardware)
Its easy to replace thankfully (assuming you have a spare and a soldering iron to hand)
If you fire up the PC and look at megatune there is a fuel pump indicator to show whether it is on or off so worth hooking up a laptop to check to see
what it thinks is going on
It does turn the fuel pump off if the engine is not seen as cranking or running (sub 600 RPM?) after a few seconds
(it should turn on to prime the system when ignition is first turned on though)
again check by using megatune to see the fuel pumps status onscreen
I don't know of a way to turn it on and off manually in software, sorry
I /think/ I blew my fuel pump tranny with some cobbled together wiring in the excitement of getting it all going
the fuel pump output on ms just grounds out to activate the pump, so use it to trigger a relay for the pump (it doesn't put out +12v and you MUST
use a relay due to the current a pump will draw)
- you possibly know this but thought I'd add it as I /think/ I managed to bugger my first transistor by momentarily getting something wrong as I
tried to smack the car into reverse and something touched something else in my cobbled temporary loom that made my tranny go pop and lost the fuel
pump
(shouldn't be an issue on the stim and a PP3 battery though?)
Regards
Rob
There can be fuel pump issues if the ign setup is wrong. As you don't say which code you are using then thi could be an area to look at. Also the
squirt should only ne powering a fuel pump relay coil not the pump direct. If you've done t direct then perhaps you've done some damage to
it.
OOPs
Note to self
must read all posts in order not to repeat a previous reply.
[Edited on 23/8/09 by omega 24 v6]
Thanks chaps,
Where is the fuel pump indicator in megatune as i've not noticed it?
How can you tell if the FP tranny is dead, had a look earlier at the fuel pump area on the board and they all look OK....
Running MS1 on V3 board.
Yes the pump is run via a relay, 12V + feed across the relay to pin 37 then via the MSboard FP cicuit to earth.
As far as code goes , i think i'm running std code and fuel only (sparks are via original OEM ignition box) could this be a problem?
The engine runs OK (not tuned) but i have to bypass the fuel pump relay to run the pump manually (i.e. running all the time).
Ash
Fuel pump is on the bottom left of megatune ( the boxes along the bottom with "fan, output one output2 etc along it.
It will be red if the board transistor is Ok and the config is OK.
Not sure about fuel only but look in
Basic settings>codebase and output functions> and make sure that the choose one code type boxes are all off.
Usually what happens is that the codes are conflicting with each other and this results in a PULSING fuel pump and can be seen at the bottom left of
the screen as the fuel pump flashing off and on in red.
You could try grounding the transistor leg ( make sure you get the right one) and seeing if that runs the oump. If it doesn't then maybe the
trannys fried.
My tranny looked perfect, wasn't burned or looked any different from when it was working
If in megatune it says pump is running and the output to fuel pump is not going to ground (or working on the stim) then it could well be that the
tranny has given up
However...
I did put a multimeter across the output on mine(too tight to buy or build a stim), and it was going to ground when it should...but just not operating
the relay and it did my head in for a while trying to diagnose what was going on
I replaced the tranny as a last resort and it all worked 100% since :-/
From memory it was a 2n222 transistor
(black plastic type) and got replaced by a round metal can version 2n222, as that is all I had to hand
Don't know anything about the V3 boards so not much help ...sorry
Maybe go through the setup and tell it something dumb so it flashes the fuel pump on and off so you can measure the pulses from CPU to tranny - and
tranny to ground
(or just use the stim and see if the LED turns on and off)
Regards
Rob
Fired up the laptop & stim last night to check again....
My copy of megatune has several options when you start, B&G original code, extra code, microsquirt etc... i've always used the B&G
original code one which works and displays the dials working OK, but there is no reference to the fuel pump etc... trying one of the other options on
start up, yes i see the fuel pump box at the bottom but the MS wont connect, checked the com settings and they match the original code program.
Also noticed, on the stim of i drop the revs right down to zero the fuel pump LED comes on but as soon as you increase the revs the LED goes out, any
ideas?
Ash
quote:
Also noticed, on the stim of i drop the revs right down to zero the fuel pump LED comes on but as soon as you increase the revs the LED goes out, any ideas?
Right
First off you need to KNOW what code is in the megasquirt before using the lappy and set the lappy up with a "profile" exactly matching your
settings, you cannot just jump willy nilly from firware to firmware and configs on the lappy
(you would have got a warning ref table corruption when it estabishes comms no?)
If you are unsure - best bet is to get the latest firmware (suitable for your hardware and intended config) and re-flash the megasquirt (you will now
know what firmware and config it is expecting) and let the configurator know what firmware and features it has
Best to start again from scratch with firmware and profile TBH
(after reading the manual a bit more)
If you intend running spark at some point the "extra" firmware is the one you want :-)
I would say that the hardware is more than likely fine, its just you have confused it into silence by the missmatch of version/config/firmwarebetween
PC and brain
Regards
Rob
[Edited on 24/8/09 by robocog]
Righty then...... looks like the safe option is to reflashthe firmware, i've got a bit of reading to do then as i have no idea how to do
this
Yes i built it myself (in true kitcar fashion!)
At least i know it generally works and runs the engine, now to set up my own map tailored better for my install.
Any pointers to the firmware version i should be after? not really fussed about running the ignition via MS if the std ignition works (which it does)
unless there is a gain to be had, only issue is the trigger wheel on the blackbird engine is a bit odd and i dont want to go down the route of
external pulleys and trigger wheels.
I must say this forum is much more helpful than the official megasquirt one!
Off to to some reading and i'll update my progress.....
Well, reflashed the MS with std code firmware but with the stim plugged in the FP LED still only lights with zero RPM, as soon as the revs increase
the LED goes out.
Could this be a fried tranny?
sounds like its acting in reverse!!
I would expect the LED to light with rpm and go out after a few seconds of no rpm
As said I do not have a stim so maybe this is what its supposed to do..though sounds reversed to what I would expect
Maybe the tranny has been put in the wrong way round?
Someone with a stim will no doubt jump in and clarify :-)
Regards
Rob
Decided to reflash the firmware again but opted for MSnS Extra this time to see if it makes any difference, opened up megatune choosing the MS1 extra
option and the fuel pump light on the software (bottom left of the screen) said fuel pump on, however the LED on the stim was out? when the revs were
dropped to zero the software said fuel pump off but the LED on the stim was on (glowing dimlly) could my stim be giving me false readings?
Reflashed with std code and noticed that after the upload the hyperterminal screen said What? above the boot prompt? this didn't happen on the
msns Extra firmware reflash?
Should i use the MSnS extra firmware even though i'm only running fuel as it gives me more info on the megatune screen.
How do i check the circuit for damage?
All the bits for the fuel pump circuit are fitted correctly.
Cheers
Ash