Engine 1990 GT Randomly Dies is undriveable

84blkstang

Member
Jun 4, 2003
542
0
16
Springfield MO
Visit site
I have a 1990 GT, 306 H/C/I 5 speed 24lb injectors CAI, C&L mass air meter. it has the AL9 CPU with a BAMA tuning chip.

A little history.

During COVID quarantine I decided to start working on the car again after not driving it much. It was basically undriveable and would die randomly and not start. I could not pinpoint a precipitating factor that would cause it to die, but I found the starter cable was pulled out of the eyelet connector, but surrounded in heatshrink which made it hard to see so I replaced the cable with new ends.

Fast forward
I pulled the engine while focused on possible electrical issues causing it to die.

ELECTRICAL FIXES
Replaced the starter cable
Replaced the alternator cable
New starter
I went through and hid the entire wiring harness I replaced all the cheap or broken connectors with soldered/heatshrinked eyelets,
I re wrapped the entire harness with new loom.
cleaned each salt and pepper shaker and replaced the engine, and electrical grounds.
New speed sensor connector
Added a taurus electric fan with the FAL controller--> works awesome BTW
Motor
New distributor cap and Roto bug
New water pump
New Coil
New throttle body, egr and spacer gaskets
New valve covers with vacuum new hoses and PCV valve
New plug wires
New LMR fenderwell CAI
new harmonic balancer
Body
New grounds
new starter solenoid
new engine to body ground
New front Shocks

The only code I get is 11, TPS is 0.98v Fuel pressure with line off is 38psi, timing is 12*,

I'm at a loss at what else to look for. If I drive it down the road it does great then randomly dies, sometimes you can feather the throttle and it will stay running. Sometimes when it dies it wont start right back up without holding the throttle open like its running out of gas, but I know there is at least 5 gallons of gas in the tank.
 
  • Sponsors(?)


jrichker

StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
27,282
2,631
234
74
Dublin GA
lowendmac.com
I have a 1990 GT, 306 H/C/I 5 speed 24lb injectors CAI, C&L mass air meter. it has the AL9 CPU with a BAMA tuning chip.

A little history.

During COVID quarantine I decided to start working on the car again after not driving it much. It was basically undriveable and would die randomly and not start. I could not pinpoint a precipitating factor that would cause it to die, but I found the starter cable was pulled out of the eyelet connector, but surrounded in heatshrink which made it hard to see so I replaced the cable with new ends.

Fast forward
I pulled the engine while focused on possible electrical issues causing it to die.

ELECTRICAL FIXES
Replaced the starter cable
Replaced the alternator cable
New starter
I went through and hid the entire wiring harness I replaced all the cheap or broken connectors with soldered/heatshrinked eyelets,
I re wrapped the entire harness with new loom.
cleaned each salt and pepper shaker and replaced the engine, and electrical grounds.
New speed sensor connector
Added a taurus electric fan with the FAL controller--> works awesome BTW
Motor
New distributor cap and Roto bug
New water pump
New Coil
New throttle body, egr and spacer gaskets
New valve covers with vacuum new hoses and PCV valve
New plug wires
New LMR fenderwell CAI
new harmonic balancer
Body
New grounds
new starter solenoid
new engine to body ground
New front Shocks

The only code I get is 11, TPS is 0.98v Fuel pressure with line off is 38psi, timing is 12*,

I'm at a loss at what else to look for. If I drive it down the road it does great then randomly dies, sometimes you can feather the throttle and it will stay running. Sometimes when it dies it wont start right back up without holding the throttle open like its running out of gas, but I know there is at least 5 gallons of gas in the tank.
You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. It includes how to dump the computer codes quickly and simply as one of the first steps. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix. :D

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 250,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
  • Useful
Reactions: General karthief

Blown88GT

Founding Member
Nov 13, 1999
2,132
497
134
Palm Beach Gardens, FL
...
The only code I get is 11, TPS is 0.98v Fuel pressure with line off is 38psi, timing is 12*,

I'm at a loss at what else to look for. If I drive it down the road it does great then randomly dies, sometimes you can feather the throttle and it will stay running. Sometimes when it dies it wont start right back up without holding the throttle open like its running out of gas, but I know there is at least 5 gallons of gas in the tank.
Could be the fuel pump is bad.
You need to monitor fuel pressure under load. It can be good at idle but fall off under load.