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First fire up non start

  • Thread starter Thread starter Driver460sz
  • Start date Start date Mar 3, 2021

Driver460sz

5 Year Member
Jan 14, 2019
145
51
38
New Hampshire
Mar 3, 2021
#1
  • Mar 3, 2021
  • #1
I will start with, yes, I know, there are or is an amazing shared checklist for problem seeking. I have read it, followed it and at this time, have lost my way.

I just installed my motor, deleted some things (Vacumme related), rewired and tucked most wires not on the firewall, now have a microsquirt ECU. It is a 302 to 351w swap project.

Upon first time start it just cranked, nothing. I checked fuel pressure and it took three key turns to get to 40 but would not start from there. I have an inline spark tester and it shows all plugs are firing. I pulled the Dist and hooked it up and rotated it to hear injector action, which seemed like some are not firing (Next check, noid light is coming tomorrow).

So it seems I have some fuel, some spark but not sure on injectors. Howvere, all injector plugs check out with volatage simliar (minor draw) to the battery. The plugs firing shows me the coil is good.

I questions the starter and the MS tune as the car cranks SUPER slow when compared to anything else I have (Car, truck, sled), its slow.

After I check the injectors (Noid light) and varify they are firing, and spark is already varified, should i?
1. Swap fuel pumps, which I have a 255 not in it yet, rolling on stock?
2. Swap injectors as they are not hig h price ones and maybe not flowing correctly (47ln EV6 now)?
3. Change the starter, maybe it's junk (It was fine when I pulled the OG 5.0)?
4. Tune issue (Which I do not think it is. A91 hooked me up)?
5. Adjust cranking speed on the MS file?

Again, I know there is a checklist. I have seen it. But I feel I am into a few systems and wondering what is next.

Any help or suggestions would be appreciated. As this is a new motor I am struggling with trying to start ittoo many times and messing up something on the break-in (351w motor).
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,720
214
Hillsborough county
Mar 3, 2021
#2
  • Mar 3, 2021
  • #2
The cranking speed in the Tune file is NOT how fast the engine will turn over..... its when the ecu moves from cranking fuel to running fuel...

The starter and battery will determine how fast the engine rolls over while cranking.

its a fresh build, on a tune that has no run time. after you verify all the injectors are firing, verify that the distributor is not 180* out.

after that its in the tune, could need more/less fuel, throttle adjustment, timing may not be sync'd ect.

worst case you let me log into your pc and we get it running
 

Driver460sz

5 Year Member
Jan 14, 2019
145
51
38
New Hampshire
Mar 3, 2021
#3
  • Mar 3, 2021
  • #3
a91what said:
The cranking speed in the Tune file is NOT how fast the engine will turn over..... its when the ecu moves from cranking fuel to running fuel...

The starter and battery will determine how fast the engine rolls over while cranking.

its a fresh build, on a tune that has no run time. after you verify all the injectors are firing, verify that the distributor is not 180* out.

after that its in the tune, could need more/less fuel, throttle adjustment, timing may not be sync'd ect.

worst case you let me log into your pc and we get it running
Click to expand...
Thank you for the input. I appreciate it.
 

Driver460sz

5 Year Member
Jan 14, 2019
145
51
38
New Hampshire
Mar 8, 2021
#4
  • Mar 8, 2021
  • #4
a91what said:
The cranking speed in the Tune file is NOT how fast the engine will turn over..... its when the ecu moves from cranking fuel to running fuel...

The starter and battery will determine how fast the engine rolls over while cranking.

its a fresh build, on a tune that has no run time. after you verify all the injectors are firing, verify that the distributor is not 180* out.

after that its in the tune, could need more/less fuel, throttle adjustment, timing may not be sync'd ect.

worst case you let me log into your pc and we get it running
Click to expand...
Got her started. Surging at idle and it shoots up to 220+ in like 90 seconds. Is this something about open loop while the ecu figures stuff out. I am going to swap in the old thermostat that worked fine in the old motor. But I am getting rad fluid through the whole system. Just not sure why it is so hot so fast. The computer shows hot while the dash gauge does not. Any ideas on that? Outside of a small header gasket leak, it all checks out. Never got to run it for 20 mins as a break in but its a roller.....so not really needed. Thanks for the help along the way.

Scott
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,720
214
Hillsborough county
Mar 8, 2021
#5
  • Mar 8, 2021
  • #5
Driver460sz said:
Got her started. Surging at idle and it shoots up to 220+ in like 90 seconds. Is this something about open loop while the ecu figures stuff out. I am going to swap in the old thermostat that worked fine in the old motor. But I am getting rad fluid through the whole system. Just not sure why it is so hot so fast. The computer shows hot while the dash gauge does not. Any ideas on that? Outside of a small header gasket leak, it all checks out. Never got to run it for 20 mins as a break in but its a roller.....so not really needed. Thanks for the help along the way.

Scott
Click to expand...
Did you go through and calibrate all the sensor inputs?

It's not an open loop thing, tuning has to be done.
 

Driver460sz

5 Year Member
Jan 14, 2019
145
51
38
New Hampshire
Mar 9, 2021
#6
  • Mar 9, 2021
  • #6
a91what said:
Did you go through and calibrate all the sensor inputs?

It's not an open loop thing, tuning has to be done.
Click to expand...
Everything is calibrated. Trigger wizard and car at 12. Which seems low, but thats where she will actually start up and idle at 1200. Wondering if there is an issue there. Everything else seems good. EGO, MAP, Coolant (Still shoots to 240 very quickly). Should I change the ohms from 2490? I have to be missing something. Oil pressure is at 42psi and the coolant hoses are all blown up when HOT (Lower and upper). What's next? Appreciate the support! Double checked and watched your timing video today.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,720
214
Hillsborough county
Mar 9, 2021
#7
  • Mar 9, 2021
  • #7
You could simply have an air bubble in it [those show real hot real fast]

If you need help I can always log in and get you idling ect. just have to get you on my schedule... [im a busy guy] but I offered so it still stands
 

Driver460sz

5 Year Member
Jan 14, 2019
145
51
38
New Hampshire
Mar 9, 2021
#8
  • Mar 9, 2021
  • #8
Driver460sz said:
Everything is calibrated. Trigger wizard and car at 12. Which seems low, but thats where she will actually start up and idle at 1200. Wondering if there is an issue there. Everything else seems good. EGO, MAP, Coolant (Still shoots to 240 very quickly). Should I change the ohms from 2490? I have to be missing something. Oil pressure is at 42psi and the coolant hoses are all blown up when HOT (Lower and upper). What's next? Appreciate the support! Double checked and watched your timing video today.
Click to expand...

a91what said:
You could simply have an air bubble in it [those show real hot real fast]

If you need help I can always log in and get you idling ect. just have to get you on my schedule... [im a busy guy] but I offered so it still stands
Click to expand...
Sure, if you have time put me in for something. I will send you a message.
 
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