That is probably the best thing to do at this point. Get it running save .msq as "yourpickfilename" on desktop some where. Now you have a safe tune to always fall back on, if you make some good changes and there is no problems save that as your fall back. Don't make a lot of changes at one time, to hard to track what could be a problem if there is one. Pick one item get it dialed in and then move one.

Start up and Idle is probably the hardest thing to tune , be patient.

GLHF

well i found the info i need to check the injector circuit so i will do that and repair what ever is wrong

ok i did what Megasquirt said to do to test the circuit and it checked out fine i touched pin 21 & 22 to ground from U1 40 pin daughter board and the injector lights light up on the jimstim so i am not sure if i have a bad fuel reg or bad setting for the injectors

check your pm

i checked fuel pressure it is 58 psi the book said 61 psi so it is off a small amount but not enough to make the problem i am having . i ordered all new components for the injection circuit in the megasquirt and if i can ever figure out where the msq file is on my computer i will send it to you kemp3

Open your current tune, Go to file and save tune as , select your desktop as the save location.

ok i will try saving a msq to the desktop

I need all the info on your motor;

displacement
injector size
firing order
crank info tooth count
cam info tooth count
so on so forth

It looks like your running wasted spark and semi-sequential or batch fire fuel ?
then I can understand the msq you sent me.

ok 4172 cc firing order 15486372 bore size 84.5 mm stroke 93 mm 300 HP@ 6000 , 295 FT LBS @ 3000 rpm , 60 tooth crank wheel 2 teeth missing no cam input 19.8 pounds per hour injectors batch fire semi seq , wasted spark coil on plug tooth 1 120 degree btdc

i don't get it i have it running but i cant get it to idle so i change the megasquirt to do pwm idle valve then the injectors stop working it is driving me nuts . i checked every thing on the megasquirt and it is right it shows that the injectors are firing when hooked to the Jimstim test board do i need to build some sort of board with mosfet relay to get this thing to work now when it worked before

quote Originally posted by engine man: firing order 15486372

Is that using "Chevy numbering" or Audi numbering?

Europeans use cylinder numbering conventions which are mystifying and illogical to those who grew up with Chevies.

quote Originally posted by engine man: i don't get it i have it running but i cant get it to idle so i change the megasquirt to do pwm idle valve then the injectors stop working it is driving me nuts . i checked every thing on the megasquirt and it is right it shows that the injectors are firing when hooked to the Jimstim test board do i need to build some sort of board with mosfet relay to get this thing to work now when it worked before

sounds like you may have a hardware conflict, could you be using the idle circuit to drive an injector ?

MS2 extra doesn't have the same features as the MS3 so I am not sure of the hardware limitations.

When I looked at your tune I only noticed a few things that may be an issue. Your required fuel should be rechecked, also in general settings it says you have 4 injectors and I believe you have 8. I also recommend changing your batch fire from 2 squirts to 4 alternating, 2 squirts means you have 4 injectors firing off at a time . How did you come to your dwell time ? if your coil near plug I say try 3.5ms at the least. How did you figure out your tooth#1 angle ? Lastly for your idle tuning turn off ego control , depending on your settings it could mess everything up. Wait till you get a WBO2 then you will have a much better idea of whats going on. I would not go out and load the motor till I had one.

glhf

tooth angle was done by finding tdc with a TDC stop then counting the teeth from the first tooth to tdc 20 teeth so 20 X 6 degrees per tooth = 120 and it ran before i tried to go to the pwm idle circuit i will go to 4 pulse on the injectors i did see the 4 injectors after i sent that to you and changed that but it did nothing . the thing i dont get is the jimstim shows the injector circut working perfect thats what i don't understand how every thing checks out to be working but it wont run now even though it ran before sure it was running rich but it ran

still nothing so id did a voltage check while cranking and i have 9.5 at the injector power pin but if i hook it up so that it is being powerd like a injector i am only getting .5 volts so why am i not getting the voltage i need i put a brand new U4 in and Q1 & Q5 so that is all new

I am confused now, does it still run when you have your idle control disabled and then not work when you enable idle ? If so can you use one of your remote ports ?

I know you are so close to running and eager but maybe send it in to DIYautotune and have them bench test it. See if they can recreate the issue , hell it may be a conflict in firmware that James has to look investigate .

glhf

no it wont run i have checked every thing on the megasquirt it seems to be working like it is supposed to so the next thing i am going to try is cranking the engine with the injection disconnected and observe the fuel pressure then connect the injection and do the same and see what the fuel pressure is if the injectors are firing at all it might be lower on the fuel pressure if the fuel pump cant keep up i tried a noid light for fuel injectors but it is not lighting up. the thing i cant understand is it looks like it is working perfect on the jimstim the injector lights blink just like they should i pulled a injector today and looked at it and looked up the number it was a high imped so and it's flow was a bit more 20.1 lbs hr not the 19.8 so i changed that but that dint work

[This message has been edited by engine man (edited 10-27-2014).]

can you tell me more about your coils ? part number ?

pull your FP fuse , go key on and use the output test mode - inj/spk. Test each injector at a time, Output interval 150 (800 rpms), pulsewidth 4 ms , Total number of injections 5. Start with Inj A (cyl 1) you should be able to hear it click or at least feel it. Continue to Inj B (cyl 5) so on so forth , do not fire the injectors dry to many times it may damage them.

you can test your coils in a similar manor , Coil A (cyl 1) and Coil E (cyl 6) should both fire . Now in the test mode it may not be true but every coil should fire when selected.
Coils A&E (1&6) Coils B&F (5&3) Coils C&G (4&7) Coils D&H (8&2) in wasted spark should fire together.

Last note on tooth#1 angle , you found it to be 20 teeth from missing @ TDC. 2 things to know you can be anywhere from 114* to 126* depending on the rising or falling edge. You will need to verify your timing once your running with a timing light and timing marks. Also you could be 360* off, when you checked TDC did you verify it was on compression stroke ? if not could have been exhaust stroke. It shouldn't be a huge issue as your running wasted spark but may make a difference.

this all started when i tried to modify the pwm on the megasquirt to try and get it to idle. I can put q4, q20 r39 and d8 back so the board is the way it was when it ran but wouldn't idle with with out my foot on the pedal

is there anyway you can open your idle valve by hand a little ?

drill small hole in throttle plate

megasquirt manual needs to change the word should use a mica insulator to must use because that was the whole problem now it runs Grrrrrrrrrrr

[This message has been edited by engine man (edited 10-30-2014).]

without a WBO2 and a datalog I cant help much , but a hunting idle sounds lean to me.

Is your narrow band reading in TS ? if so run a datalog and email it to me.

ya i need the wide band and just amgoing to have to buy a more expensive one since they dont seem to be getting that one back at 14point7 but i have a video of it running the sound sucks due to cheap caera and microphone
https://www.youtube.com/watch?v=XJ0BG-6jeSs

congrats

on the slight surge in your idle I would guess maybe a little to much timing or still a little lean.

get a WBo2 and tuning will be a breeze.

Thanks i will get the WBo2 in a few weeks but i have to get the 72 Mercedes in shop and running for my customer then i will have some more money

I just want to say building this car is fun and anyone who might want one like it i hope this thread helps you it really wasn't that hard to build i still need to do some bracing and clean up the wiring and i want to thank all the guys who helped with good ideas and pointing me in the right direction

[This message has been edited by engine man (edited 11-01-2014).]

tomorrow i am going to try to register the car and bleed the brakes and go for a ride i sure hope i can do this at lunch time

Have you welded in braces for your modified cradle as we discussed earlier in the thread?

It would be a shame to go through all of this and then have that cradle fold up the first time you took a corner.

no and i need to do that before the road test i did get it registered but i need a new RR caliper so i can stop

That helps too.

RR caliper showed at the shop but wait right box but wrong caliper so they have to get me another

Will i did some welding today i got the braces welded in so there should not be a issue when i go into a corner

well now i can make the wiring look better and repair the wiring inside that the previous owner messed up and looks like a 2 year old did

rear braces

1" square tubing? .060" wall thickness? Looking at that vs. the stock rear crossmember on the cradle, I'd want a more extensive truss on your modified cradle. You may want to make a bolt-in brace that goes above the transmission.

For example, if you're in a hard left corner, the lateral links are going to be pushing left on the right cradle rail. The way you have it now, that tries to bend the horizontal tubing in the middle.

The way you have it now is better than it was... now you're depending on the bending strength of that square tubing. Before, you were depending on the bending strength of the 90 degree joint.

EDIT:

I'd want to build a truss like this before I'd feel good about working that car hard:



EDIT 2: Obviously the truss would go up in plane with your rear crossmember and the rear cradle mounts... not sticking out behind the car

[This message has been edited by Will (edited 11-11-2014).]

i am using .083 wall not .060 and i don't know if you can see but i put another 1 x2 under the crossmember in the center to stiffen it up and i feel it is as strong if not stronger than stock but that is just my opinion