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Engine 1987 GT surging and dies when trying to start

  • Thread starter Thread starter LASAR
  • Start date Start date May 20, 2018
L

LASAR

Member
Sep 7, 2013
17
1
14
May 20, 2018
#1
  • May 20, 2018
  • #1
1987 GT was my son's first car. He's 33 now so we've had it a while.
It sat in the garage for the last ten years.
Have replaced injectors, MAP sensor, air charge temp sensor, coolant temp sensor, and egr valve.
Car surges and dies when we try to start it.
Take about 5 minutes of cranking and playing with the accelerator to get it to run without dying,
Even then it took a while to smooth out. When out on the highway and ran good for about 2 miles and started running bad.
Just made it home. Was still surging. Seemed like it ran better if I kept it at 2500-3000 RPM.
Only codes are 41, 91, and 82 but these seem related to emissions.
Another strange thing is that after idling it at 2500-3000 RPM it would idle down to around 1500 RPM until I pushed the clutch in, then it dropped down.
I can usually figure out how to fix stuff on my '56 Country Sedan, but trying to figure out all this "new" stuff quite a challenge.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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May 20, 2018
#2
  • May 20, 2018
  • #2
lets figure that after sitting that long you have changed the stuff like plugs, wires and checked for cridders in the filter box, drain the old fuel and changed the fuel filter. And of course that stale air in them tires too
If you have problems with surging, rough idle and stalling there is a checklist for that: http://forums.stangnet.com/showthread.php?t=698148
Read over the list, get familiar with it, gather up your tools and dig in, it was put together by jrichker and he is glad to help. Don't skip around, do it step by step, it will save you time and money. there are other helpful stuff in the fox tech/how to thread from brake upgrades to engine swaps, if you get stuck the members will help you.
 
L

LASAR

Member
Sep 7, 2013
17
1
14
May 21, 2018
#3
  • May 21, 2018
  • #3
General karthief said:
lets figure that after sitting that long you have changed the stuff like plugs, wires and checked for cridders in the filter box, drain the old fuel and changed the fuel filter. And of course that stale air in them tires too
If you have problems with surging, rough idle and stalling there is a checklist for that: http://forums.stangnet.com/showthread.php?t=698148
Read over the list, get familiar with it, gather up your tools and dig in, it was put together by jrichker and he is glad to help. Don't skip around, do it step by step, it will save you time and money. there are other helpful stuff in the fox tech/how to thread from brake upgrades to engine swaps, if you get stuck the members will help you.
Click to expand...


Thanks. Looks like good plan. Just hope the old brain cells can comprehend it all. If not, I know where to find help.
 
Reactions: General karthief

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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May 21, 2018
#4
  • May 21, 2018
  • #4
LASAR said:
Only codes are 41, 91, and 82 but these seem related to emissions.
Click to expand...

Code 41/91 aren't necessarily emissions codes. They could signify a pretty large vacuum leak which would cause the exact symptoms you are seeing. You'll want to troubleshoot this and clear these codes

https://www.stangnet.com/mustang-forums/threads/code-41-and-91-wont-go-away.882046/
 
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