• Mustang Forums
  • Digital Self-tuning Forum

Microsquirt issue. Car won't start with SPOUT in

  • Thread starter Thread starter sw1tched007
  • Start date Start date Mar 13, 2020
S

sw1tched007

New Member
Mar 13, 2020
4
0
1
Latrobe, PA
Mar 13, 2020
#1
  • Mar 13, 2020
  • #1
Got a Microsquirt and PNP harness from EFI Source for my foxbody. It will start and run with the SPOUT out but as soon as I plug it in the car shuts off and will not start. Had a few problems at first due to the resistor in the harness touching multiple pins and ruined my TFI and PIP. Replaced distributor and now all that stuff tests good. I tested the resistor that is in the harness and it is reading 331 ohms but in the microsquirt manual it calls for a 1000 ohm resistor. Not sure if this would be causing the issue or not.

Just looking if anyone has any ideas of what else could be causing this issue. Car started and ran fine prior to installing the microsquirt and harness.
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Mar 13, 2020
#2
  • Mar 13, 2020
  • #2
@a91what

I'm not well versed with microsquirt or the pnp harness. I run mspnp2. Make sure all the wiring pins are going where they are supposed to. Im sure you've already checked all that. It seems like with the spout out it would be running on mechanical timing. Plugging it in seems like it would allow the microsquirt to take over. Did you set up the timing properly in TS. Offset should be 10°. Can you post a tune file and a datalog ?

I had serious issues getting my car started a couple years ago. A91what was a huge help. He's gotten busier but is always willing to help. If I were in your boat I'd call or message him and give him a little scratch to get it started and the first tune. Actually, I pay him and watch the magic happen on my lap top.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,721
214
Hillsborough county
Mar 13, 2020
#3
  • Mar 13, 2020
  • #3
Please post the tune you are working with for review
 
S

sw1tched007

New Member
Mar 13, 2020
4
0
1
Latrobe, PA
Mar 13, 2020
#4
  • Mar 13, 2020
  • #4
Here is the tune I was using. I can get a datalog in the morning and attach it as well.
 

Attachments

  • startup no spout.msq
    startup no spout.msq
    117.6 KB · Views: 216

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,721
214
Hillsborough county
Mar 13, 2020
#5
  • Mar 13, 2020
  • #5
I see alot i would change on the tune but nothing that should stop it from working, I even checked it against a known good tune.
 
S

sw1tched007

New Member
Mar 13, 2020
4
0
1
Latrobe, PA
Mar 13, 2020
#6
  • Mar 13, 2020
  • #6
Any ideas what would be causing it to not run when I plug the spout in? I will attach a datalog in the morning if that would show anything.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,721
214
Hillsborough county
Mar 13, 2020
#7
  • Mar 13, 2020
  • #7
please do.
 
S

sw1tched007

New Member
Mar 13, 2020
4
0
1
Latrobe, PA
Mar 14, 2020
#8
  • Mar 14, 2020
  • #8
Here is a datalog of trying to start with spout in and starting with spout out. I hooked up the stock ecu, unplugged the map sensor and kept the spout plugged in and it started with the stock ecu.
 

Attachments

  • Spout in 2020-03-14_08.42.53.mlg
    Spout in 2020-03-14_08.42.53.mlg
    44.5 KB · Views: 195
  • Spout out start 2020-03-14_08.42.53.mlg
    Spout out start 2020-03-14_08.42.53.mlg
    130.5 KB · Views: 212

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,721
214
Hillsborough county
Mar 14, 2020
#9
  • Mar 14, 2020
  • #9
The first thing i see is the MAP signal and the sensors freak out during cranking... This is the same behavior that kills the a9l stock ecu, I believe when you are cranking the NSS circuit is feeding 12v onto the signal ground. this is a major issue. This needs to be found and addressed as soon as possible. do you still have the stock O2 sensor harness installed? if so unplug it

I see rpm in the log file on the no start condition so it is the TFI that is not firing. try and remove the pullup resistor first as a test.
 
You must log in or register to reply here.

Similar threads

Electrical 88 EEC Injectors batch firing ?
  • Dustin 86GT
  • Dec 8, 2025
  • Fox 5.0 Mustang Tech
Replies
10
Views
436
Fox 5.0 Mustang Tech Jan 8, 2026
gkomo
H
Fuel starvation issues, 91 EFI to carb swap. Car dying after 1-3 gallons used. EFI tank, electric fuel pump, bypass regulator. Dual fed carb
  • hassler
  • Oct 11, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
8
Views
768
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 12, 2025
nickyb
C
Electrical Multiple spark with spout in, normal when out
  • Cumstang59
  • Dec 28, 2024
  • 1994 - 1995 Specific Tech
  • 2
Replies
24
Views
1K
1994 - 1995 Specific Tech Feb 5, 2025
Cumstang59
C
A9L on 94 engine, no priming injector pulse?
  • Wallyman
  • Jun 17, 2024
  • Other Auto Tech
Replies
11
Views
1K
Other Auto Tech Jun 24, 2024
Wallyman
1999 Mustang GT - No Start- Need help understanding the fuel pump circuit and how it works
  • 99gtGuy
  • Nov 4, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
1
Views
524
1996 - 2004 SN95 Mustang -General/Talk- Nov 7, 2025
04newedge-
0
Share:
Bluesky Email Share Link
  • Mustang Forums
  • Digital Self-tuning Forum
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?