4.9 no iac first start help

[twinturbor]

It won't fire off either wire on inj1. Inj 2 wires fire the injectors just fine. Unless I accidentally found a way to just turn that one channel off its dead.

[Matt Cramer]

It won't fire off either wire on inj1. Inj 2 wires fire the injectors just fine. Unless I accidentally found a way to just turn that one channel off its dead.

What main board version is this?

[seijirou]

It won't fire off either wire on inj1. Inj 2 wires fire the injectors just fine. Unless I accidentally found a way to just turn that one channel off its dead.

What main board version is this?

3.57

[Matt Cramer]

Try this testing guide: https://www.diyautotune.com/support/tec ... or-driver/

[twinturbor]

I don't have a j stim as I didn't build my unit so testing is out the door for me

[twinturbor]

I think I'm just going to send this to somene, I bought it over a year ago so its out of warranty now even though I just got to hook it up. I've been saving parts for this build for almost 3 years and now I will just have to wait a while before i can get it done.I'm a single dad with no extra budget for emergency parts. Maybe next summer I can address what's going on with this thing thanks for all who helped me out

[seijirou]

I can do the TFI changes. I probably can't fix inj1 but I can throw it on a stim and do some diagnosis for you. Might save you some coin.

[twinturbor]

thank you. i might take you up on that. i will private message you about details

[jsmcortina]

Try Peter Florance, he can repair anything.

James

[twinturbor]

so i guess i have one more question. under fixed timing, is that number the actual timing advance or how much more over the base timing? im at 10 degrees mechanical advance and im not sure if i should command 10 or 20 degrees to get an actual 20

[seijirou]

so i guess i have one more question. under fixed timing, is that number the actual timing advance or how much more over the base timing? im at 10 degrees mechanical advance and im not sure if i should command 10 or 20 degrees to get an actual 20

It's actual. If you have 10 mechanical, you have to make sure megasquirt knows that. It's called "Trigger Angle", which should be set to match your mechanical advance.

[Twistedmetal]

Everything you enter into the MS is real world timing relative to the trigger offset.

If you command 30° in the MS, the MS is going to fire at what it thinks is 30°. So if you bring the #1 cyl to TDC compression and the indicator shows 0°BTDC, the distributor is pointing to #1 in the cap (I mark the location in the distributor base so it's easier to set) and the "Ignition Offset Angle" (Ignition setting>trigger wizard) is set to 0°, it will fire at 30°.

If you command 30°, the indicator shows 10° BTDC and the offset is 0° it will fire at 40° real world
If you command 30°, the indicator shows 10° ATDC and the offset is 0° it will fire at 20° real world
If you command 30°, the indicator shows 0° BTDC and the offset is 10° it will fire at 40° real world
If you command 30°, the indicator shows 10° BTDC and the offset is 10° it will fire at 30° real world

So you check what the reading is on the balancer and adjust the "Ignition Offset Angle" untill the commanded timing (big numbers) match the balancer reading. Pretty easy once you wrap your head around it.

Now here's the kicker...

Ford engineers back in the day, for some unknown reason (a cruel joke on future mechanics and hobbyists maybe) decided to install 2 marks on the 4.9 balancer. A big notch, which you would automatically assume is the timing mark (it's not) and a very fine scratch just barely visible and hard to find, it's about 120° away from the big notch. If you time it off the notch it will run like ass, if you time it 180° out if cam phase (360° crank phase) it will also run like ass but it will still run. I am interested in this thread, it's resolution and if you didnt live 1000 miles away I would have just offered to swing over and set it up for you while walking you through it step by step. if you have questions dont hesitate to ask. I'm doing a 4.9 turbo project too, I just finished a 5.0 turbo project.

If and when it runs, bypass the MS's spark output going to the TFI and run the coil directly off the Megasquirt, you will thank me later.

[twinturbor]

Thx. I will post the results when I get this ting done I'm going for 30psi on method once the computer is going well

[twinturbor]

My project

[Twistedmetal]

Very nice. I've been kicking around the idea of moving the injectors further up the runners on mine (about 6") because Ford failed at designing a new head for the EFI motor, that is why base pressure is 60 psi and the injectors have a cooling fan, to prevent fuel boil and injector damage. I'd be intersted to know what turbo you selected. I don't want to use the same 70mm I'm using on the Mustang, it won't spool early enough for the 300l6, I need to spool BY 2-2.5k to make it effective. I'd also be interested in pics of your hotside, are you using the stock manifolds, headers, where you hid the wastegate etc.

[twinturbor]

I will sends few more pics tomorrow. I will be out working on it. I'm using a standard gt35 with a .68 hot side. When it was on the ford computer it came on quick and hard. I'm excited to let this thing see some high boost

[twinturbor]

I might have figured out why my truck won't start now. I had the trigger on falling edge as that was the only info I could find. Set that way I couldn't see the timing marks. So I switched it and now im showing the timing I've commanded.

[twinturbor]

I can't upload any more pics for you @twistedmetal

[Twistedmetal]

That's ok twinturbor, lol. Are you using the TFI as the trigger input? I just looked at mine, I am using falling edge with my TFI trigger, I am concerned that using rising edge could cause rotor phasing issues even though it seems to be running correctly. I keep an old cap with a 1" hole drilled in it above the #1 terminal around to make sure this is not a problem, just stick the timing light in there to see where it's at. Could be a 4.9 thing as I havent installed the new box in mine yet to confirm it, but mine is falling on the 5.0 TFI distributor.

[twinturbor]

So with the trigger on falling edge I couldn't see the timing mark at all but when I switched to rising edge it showed perfect. Im going to try and start it again soon but vacation prep has slowed things a bit.