** MegaSquirting a V8 - "Basics of How to" ... The A-Z Saga

[Hybrid_From_Hell]

Mine seemed to need bucketloads of fuel on AE, it doesn't respond properly otherwise. Tunerstudio has a nice realtime O2 gauge along the bottom for seeing if your AFR is too rich or lean during AE (you want it fairly consistant) which makes tuning it much easier.

Nothing too non standard about my engine - no airbox though which may affect the intake?

PID closed loop idle: I've not heard from KeithG in a couple of months - will ask if he has new code.

IMHO AE is one the the most tricky to sort, and with engines that are even the same on paper

in reality AE can work well on one yet the same settings no so well on others.

Its a bit like how some V8 start easily on 2nd crank and others are a pain needing 8 cranks before

they think about starting. Similarly some V8s go like absolute stink and the same engine in

another identical car set up the same er doesn't there seems no reason for it,

yet this is the case esp around AE, also too rich / too lean can feel the same and can equally be confused for AE issues

Tom is right with what he says, but AE is waaay down the list to get to

1st ensure the main basics inc ve is logged and about right, rome wasn't built in a day

and neither will any MSQ, start with the basics, understand what you are doing and the efffects

it has an work through slowly and gently improving each time where you can. Fine tunning

ends up with you getting less and less each time in terms out outright "wowness" but it pays off

Nige

[FridgeFreezer]

So what controls the idle?

Nothing at all, I start it up and if it's really cold I have to wedge the squeegee on the throttle pedal for a minute or so while I open the gate to get the truck out, after that it's happy anyway. I do have a PWM idle valve to fit at some point but it's just not been a priority.

Don't confuse the idle air valve (which raises the idle speed) with warmup enrichment (which adds fuel), the two together have the same function as a choke on a carb setup, the choke cable usually opens the throttle butterfly slightly and richens the mixture.

There are distinct phases to the cycle in MS:

Cranking (lots of extra fuel, about 10x in fact)

After-start (quite a lot of extra fuel, gradually reducing over ~200 engine cycles)

Warmup (Effectively choke, extra fuel depending on engine temperature)

Normal running (Once engine is warmed up)

[Hybrid_From_Hell]

Nothing at all, I start it up and if it's really cold I have to wedge the squeegee on the throttle pedal for a minute or so while I open the gate to get the truck out, after that it's happy anyway. I do have a PWM idle valve to fit at some point but it's just not been a priority.

Is that a std squeegee? - or a specially calibrated one ?

Nige

[Steve 90]

Steve

Before you start twiddling major sections of the MSQ I would suggest that you have already done the No 1 thing - which is to set the trim / timings 1st

2nd is to also set the calibatraion for the TPS in Megasquirt, and regap the plugs to 0.6mm and the VR to 0.75 - 1.25mm cleance from sensor

3rd is to then do a data log so as to have a rapid retune of the VE to match your engine, several times also would be better so you know the basiscs are spot on

then and only then consider anything more, its a bit like decorating your house when its on fire, yes decorating is importnant and prob needs doing, but there is a bigger and more importnant thing to do 1st

Nige

Timing is spot on now. I did it this morning and it needed 7deg trim to get it right. I will have to pull the rad back out sometime this week. Might move the trigger wheel 7 deg so I can set the trim back to 0.

TPS Calibration is a new one on me (apart from adjustable ones on some early inj cars) I'll have a look at that in the morning.

Plugs I gapped at .8mm, Will that be OK or should I change them? I couldn't find any spec's at the time and thought the coil packs were more than capable of this, Especially when the Zetecs originally ran 1.3mm gaps. If you think its too much I'll change them.

VR sensor I have much less than that. Again I couldn't find any specs so set it at .5mm. I'll change it when the rad is out.

I have not changed any settings other than the timing offset. I have spent ages looking at stuff and trying to familiarise myself with the system. I did have a really good check over the engine today and found a small air leak on one vacuum blanker. I had already checked it but must have missed the split since I fixed that its much much better. There is now hardly any hesitation at all, Its noticeable when your looking for it but when driving I'd be surprised if it was a problem. I'll know more when its out of the workshop in a couple of days.

Cheers.

Steve.

[Steve 90]

MS1 controls a PWM valve such as VW/Audi Bosch 2-wire idle valve by pulsing the power to it on and off quickly (about 100 times per second) to regulate the air bypassing the butterfly, it tries to keep the RPM to a target value (closed loop control). You can have it either warm up only or run all the time - this is great for when additional loads kick in (e.g. alternator, hydraulic pump, powersteering, etc) also works quite well as an anti-stall on manuals - point it at a hill and take feet off pedals.

The idle control algorythm MS1Extra uses work but is a bit primative and takes a bit of tuning.

Yea, I understand the idle valves, It was more a question about the trucks without. I've heard some talk of systems altering ign timing to vary idle speed, Is that right? I take it its not part of MS.

Cheers.

Steve.

[Bull Bar Cowboy]

Steve,

Assuming you are using EDIS ………To set your timing…. Disconnect the SAW from the ECU to EDIS and run the engine. You should see 10 BTDC ……. If not , then adjust the VR sensor until you do.

Set the plug gaps to 1mm

Use the MS TPS calibration facility so that MS knows what values to expect from the TPS (the actual values are unimportant, as long as MS knows what they are. Do the with engine off and ignition on…….. its just a matter of no throttle value and WOT value.

It’s best to set the idle by adjusting the plenum butterfly for about 5 thou clearance….. then use the air bypass screw for fine adjustment.

RV8’s tend to like a slight rich mixture for a good solid idle.

Set up the engine for a good idle and good overall performance, THEN think about fitting the idle control valve …….. the 2 wire is better…… mine came off a Volvo 940.

[FridgeFreezer]

I think we're in danger of veering into worrying about things that need not be worried about:

- If you have trimmed it so the timing is spot on then you don't need to adjust the trigger wheel, the only thing that really affects is the EDIS limp-home mode and the total advance EDIS can manage (both are relative to where it thinks TDC is). Neither will be a problem in this case.

- TPS calibration is not massively important, ACCEL works on speed of change, not the absolute value unlike Flapper EFI.

- VR sensor gap is not important as long as it's not too far away to read reliably.

- Plug gaps, as you say Ford run them at 1.3mm so not too critical.

As for timing to stabilise idle, that you can do in the ignition map (likewise you can change the fuel map to stabilise idle). I don't know the details on the ignition side but on the fuel side you put a slight slope around idle, such that if the RPM dips it goes slightly lean which naturally causes the engine to speed up slightly, likewise if the RPM surges slightly it goes rich which bogs it down a little - a gentle slope helps to stabilise idle in this way but too much and it will be unstable and cycle about.

A point to note on the timing & trim issue: The MegaTune "Advance" gauge shows the total advance (EG desired timing + trim angle) so will throw some weird numbers out.

[Steve 90]

- If you have trimmed it so the timing is spot on then you don't need to adjust the trigger wheel,

I was only planning on altering the trigger wheel as I will have the rad back out so its very easy and If I do I can set the trim to 0 in which case of I do ever get into swapping Maps etc I dont need to change the trim angle. But to be honnest its so simple it wouldn't be an issue so it will quite possibly get left as it is.

A point to note on the timing & trim issue: The MegaTune "Advance" gauge shows the total advance (EG desired timing + trim angle) so will throw some weird numbers out.

Yea, I discovered that last night when I was watching the laptop screen while using the timing light at idle. For no real reason other than curiosity Reasuring thing is its all bang on so I must have got the trim right.

[Steve 90]

Steve,

Assuming you are using EDIS ………To set your timing…. Disconnect the SAW from the ECU to EDIS and run the engine. You should see 10 BTDC ……. If not , then adjust the VR sensor until you do.

Set the plug gaps to 1mm

Use the MS TPS calibration facility so that MS knows what values to expect from the TPS (the actual values are unimportant, as long as MS knows what they are. Do the with engine off and ignition on…….. its just a matter of no throttle value and WOT value.

It’s best to set the idle by adjusting the plenum butterfly for about 5 thou clearance….. then use the air bypass screw for fine adjustment.

RV8’s tend to like a slight rich mixture for a good solid idle.

Set up the engine for a good idle and good overall performance, THEN think about fitting the idle control valve …….. the 2 wire is better…… mine came off a Volvo 940.

Thanks. I will sort the TPS calibration today. How important it is I have no clue but it looks simple and easy enough so why not aye!

The butterfly adjustment is pretty much as I have it. I "Tweaked" the butterfly just off its seat then needed about 1/2 of a turn on the bypass to get an idle. seems reliable and drops back to it without fuss.

I think I will probably fit an idle valve but I'll get everything else sorted before I do that.

Thanks for your input Ian, Its all very much appreciated and I get the feeling I'll be needing much much more in the coming days.

[FridgeFreezer]

Another one just because:

Full MegaSquirt-n-Spark-Extra 029v Firmware including correct coolant sensor data & download script is here:

---> 029v.zip <---

Save the Zip file somwhere.

Right-click and you should have the option of "Unzip here" or similar.

A folder called "029v" should appear once unzipped.

You will need your ECU plugged into the PC and some way of getting a +12v supply to it (this can include just taking the laptop to the car and turning the ignition on)

Run "Download-Firmware-V8.bat" and follow the on-screen instructions.

If you are upgrading from "Standard" MegaSquirt fuel-only code (B&G V3.0) then you will need to open the lid of the ECU and either put the BOOT jumper in place (2 pins next to the CPU) or short the BOOT PCB contacts with something metal (need I say you should be very careful doing this?). The BOOT jumper should be removed when done (and you won't need it to re-flash in future).

If you are upgrading or re-flashing from a version of MS-Extra then you do not need the BOOT jumper and it should be left off.

If you do not have Winzip or similar then I recommend googling for FilZip which is free, nicer, and not made by Microsoft

[FridgeFreezer]

Another one to clear up issues I get in PM's - the diagram Nige posted waaay back on page 1 is quite blurry as he's printed it out, doodled all over it with crayons and then scanned it back in so here is the original crystal clear version:

(Nige feel free to add this in to your post on page 1 )

And here's the pinout for the connector, which is closer to what most people's wiring will be like:

A few points to note:

(And please do note them before asking questions)

- The Stepper motor can only be used with MS-2 so you would usually use a PWM idle vale connected to FIDLE as shown in the connector diagram.

- Most people connect EDIS as shown on the connector diagram, the full loom it's shown as using the FIDLE output due to the loom being designed for the stepper motor.

- The EDIS connections to the coil packs are NOT representative of any particular firing order so you MUST confirm which connection on which coil pack goes to pins 8, 9, 11, and 12. Most will be wired as per the coil setup shown below.

This is the coil wiring most people will be using, so PLEASE note that it is different to both the diagram above and to the standard EDIS8 Ford wiring.

[Hybrid_From_Hell]

FFS

They were not crayons.

I'll have you know - They were 'flip chart' markers "liberated" from work

Please get your facts straight in the future Mr Fridge,

I can't nick crayons, we don't use them - if we did then I would - unless they were screwed down

then they would take a little longer to aquire

Nige

The Honest Mod

[FridgeFreezer]

Uuuuh-huh

[Boothy]

Can I just chip in to make a statement,

My good mate has a Mk1 Escort straight line 1/4 mile racer to which he has just fitted a brand new Duratec engine, he has spent an absolute fortune on this car (45K +) and choose the Emerald system for the ECU, after 18 months of building, the ECU was finally powered up and doesn't work, after a few phone calls to Emerald it's basically hard luck mate your ECU's f****d and needs a look at, which we we will charge you for, because it's 18 months old and out of warranty,even though it's never been powered up.

He's jealous to death when he reads this forum and see's what a wealth of good, solid, free information is available for the "inferior" Megasquirt system.

Makes me kinda proud to be inferior.

Just a massive pat on the back lads

[FridgeFreezer]

Why not just MS the Escort? Last time I looked Emerald doesn't do anything MS can't, they just use more complicated names to make it sound like you need one

[stuck]

Right,

Thanks to the wiring diagram above I'm ready to get started (or will be if anyone can clear something up for me )

On the drawing above two sensors are shown, namely coolant and air temperature, the wiring diagram in Haynes shows only coolant and fuel temperatures can't think why you would want to know how cold the petrol is so has Haynes got this wrong?

The wiring diagram in the manual is for a '88 / '89 EFI (Current engine)

Thanks,

Mick.

[steve_d]

The Haynes is right there are both coolant and fuel temperature sensors on your engine.

MS requires coolant temp and inlet air temperature sensors so the fuel sensor is left disconnected.

You can use the already fitted coolant sensor but will have to find and fit the air temp somewhere in the ducting you will use to connect the air filter to the throttle body once you have binned the air flow meter (MAF).

Check the thread as the most common sensor is shown in there with part number. I used a Ford one which I found at the breakers. It is convenient as it came in a nice plastic housing that fits as an inline joiner in my ducting.

Steve

[FridgeFreezer]

What Steve sai - you don't need the fuel temperature sensor but the air temperature sensor (which is part of the airflow meter as standard) will need to be replaced. Nige has posted up his solution which is Fuelparts AT1010 from memory, which is a standard GM/Renault type sensor, or you can buy RS part # 151-215 which is a tiny tiny bead thermistor but you'll have to find some way of mounting it that it won't get damaged.

[stuck]

What Steve sai - you don't need the fuel temperature sensor but the air temperature sensor (which is part of the airflow meter as standard) will need to be replaced. Nige has posted up his solution which is Fuelparts AT1010 from memory, which is a standard GM/Renault type sensor, or you can buy RS part # 151-215 which is a tiny tiny bead thermistor but you'll have to find some way of mounting it that it won't get damaged.

RS part numbers are good

Thanks for that!

[Boothy]

I used a air temp of a Laguna, it was about £12 and fitted into a M12 fine nut (I think) which was just a straight weld into my snorkel pipe, and took a standard 2 pin connection.

Fridge, for the life of me I couldn't talk him into Megasquirt, it isn't good enough, don't tell me I know what I'm glad I'm using.

[Hybrid_From_Hell]

Chris,

Your mate is of course so correct.

MS is a hugely inferior system, basic, cheap and you have to play with it yourself, suited to only

DIY sheds and heaps owned by deluded enthusiasts who don't know better.

This here is a perfect example :

Show him the above - then run

Nige

[Tom Walker]

Hey guys,

Read the entire post and am re-invigorated with respect to getting the Megasquirt in my SD1 3.5 EFi working right (not to mention awed by your experience and dedication). One of the things I'd dearly like to get organised is the fan relay control for my electric fans. Unfortuantely, I can't seem to get the right info together to build the correct circuit for my v2.2 PCB. Is anyone able to shed some light on this matter, as the diagrams I've seen refer to the other side of the relay returning to a particular pin on the ECU and I can't work out why this is necessary?

Kind regards,

Tom Walker

Melbourne, Australia

[FridgeFreezer]

Assuming you're using the MS-Extra code (since that's the version that can control fans) you need to look here:

MSnS-Extra Hardware manual

Use the circuit shown, either inside the ECU or externally. Because of the way it works the ECU will switch the ground-side of the relay coil to make it turn on so you need to feed ignition switched +12v (as shown) to the other side to complete the circuit.

[Hybrid_From_Hell]

Read the entire post and am re-invigorated

Erm yeah maybe you need to get out more you don't so much get a badge as a nurse

not to mention awed by your experience and dedication

Flattery will get you everywhere and anywhere with us sad MS geeky V8ers

Welcome to the work of Squirting

Nige

[bobtail84]

OK, so something is backfeeding into your ignition live, the ticking is the relay & PWM valve trying to actuate (probably because the MS will be trying to power up too, it uses very little current to wake up), as they try to move they load the circuit enough to drop the voltage and knock them off again, so they cycle like this.

Fridge..... After pulling all the loom out and starting with the M/S plug I worked back and found between 2 and 6 volts coming from the switched live on the ignition switch. Looking at the crayola wiring diagram I took the switched live from the main relay and BINGO.... no problems.. If anyone needs a full diagnosis, and let me tell you its long, I can post if needed.

Jeff