Car dies when put in gear

webb1624 · Post by **webb1624** » Sat Dec 06, 2014 6:36 pm

I've been tuning on my 88 Mustang for a while and have it idling decent. The problem I'm having now is when I put the car in any gear, the engine will shut off. I can work the throttle to keep it running but when I let off it will die. It almost seems like the convertor is to tight but it has a stall around 2800-3000 so it should be ok. I'm running 15 degrees of timing at idle. Is that enough when in gear? Is there a setting that recognizes that the car is in gear and adjust timing? I have checked for vacuum leaks and can't find any. The cam is on the big side and doesn't make a lot of vacuum at idle.
I'm used to working on carbureted racing engines. This is my first fuel injected project so working with the Megasquirt is new to me. Not sure if this is a tuning issue or not.

1998 Ford Explorer block 347 ci
AFR 185 heads
Holley Systemax intake
Ed Curtis cam
Mac 1 3/4 shorty headers
75 mm TB
42 lb/hr Bosch injectors
Ford Explorer ign coils
MS3 w/ MS3X expansion V3.57
LC 2 wideband (2)
4R70W with Baumann Opti-Shift controller
Precision Industries lock-up convertor 2800-3000 stall

webb1624 · Post by **webb1624** » Sat Dec 06, 2014 6:54 pm

I've been tuning on my 88 Mustang for a while and have it idling decent. The problem I'm having now is when I put the car in any gear, the engine will shut off. I can work the throttle to keep it running but when I let off it will die. It almost seems like the convertor is to tight but it has a stall around 2800-3000 so it should be ok. I'm running 15 degrees of timing at idle. Is that enough when in gear? Is there a setting that recognizes that the car is in gear and adjust timing? I have checked for vacuum leaks and can't find any. The cam is on the big side and doesn't make a lot of vacuum at idle.
I'm used to working on carbureted racing engines. This is my first fuel injected project so working with the Megasquirt is new to me. Not sure if this is a tuning issue or not.

1998 Ford Explorer block 347 ci
AFR 185 heads
Holley Systemax intake
Ed Curtis cam
Mac 1 3/4 shorty headers
75 mm TB
42 lb/hr Bosch injectors
Ford Explorer ign coils
MS3 w/ MS3X expansion V3.57
LC 2 wideband (2)
4R70W with Baumann Opti-Shift controller
Precision Industries lock-up convertor 2800-3000 stall

slow_hemi6 · Post by **slow_hemi6** » Sat Dec 06, 2014 9:39 pm

I am a bit perplexed by this as in this screenshot you can clearly see it is not doing what the tables are commanding it to do. If it was to increase VE and Timing to 60 and 18 as the tables show then I am sure it would dip much less. The msq has both idle VE and Advance turned off so that can't be the issue.

Untitled.jpg

webb1624 · Post by **webb1624** » Mon Dec 08, 2014 4:15 pm

I got some input from some other people on some things to try. I was told to lock the timing out and play with the fuel map to see if I could get it to idle in gear. I tried 25, 30, and 35 degrees of timing. I had to add fuel to the fuel map and open the IAC a little to get it to idle. It was idling around 13 afr. 30 degrees probably ran the best but half the time it would shut off when put in gear and the other half it would stay running but just barely. The car would still not be drivable. I went from 45% fuel load all the way to 70% fuel load and still couldn't get it to idle good in gear. I kept the rpm's around 850-900 each time. My IAC was open any where from 50% to 60%.
Do I need my IAC open more to give it more air ? Then add more fuel to keep the AFR's in check ??

The car still acted like it wanted to move when putting it in gear. I'm thinking it shouldn't do that with a 2800-3000 stall convertor.

Not sure what to do next

billr · Post by **billr** » Mon Dec 08, 2014 7:53 pm

Try less ignition advance at idle, like 10 BTDC or less.

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