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Engine 1989 5.0 Lx Rough Idle. Need Help Pls

  • Thread starter Thread starter Jean-Francois
  • Start date Start date May 23, 2013

Jean-Francois

New Member
May 23, 2013
6
0
1
Victoria
May 23, 2013
#1
  • May 23, 2013
  • #1
I have an 89 mustang lx and the problem I'm having is as follows:

Rough idle--searches for idle from 600-1000 rpm.
Stumbles under acceleration. Feels like its missing.

My car is mostly stock but I put 24lbs injectors cause I have to replaced the old one and I thaugh thats gonna be a good idea to upgrade to a bit higher. After all I found my car less powerfull and burn out the o2 sensors, so I changed the o2 and the MAF sensor (BBK 24lbs pre-set). Power is back but the car won't run great on idle or when is got no load. I've been chassing the problem for a while but I need Help.

Thanks

J-F
 

foxbodymike87

Active Member
Jul 12, 2011
739
35
39
May 23, 2013
#2
  • May 23, 2013
  • #2
Codes?
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
May 23, 2013
#3
  • May 23, 2013
  • #3
Jean-Francois said:
I have an 89 mustang lx and the problem I'm having is as follows:

Rough idle--searches for idle from 600-1000 rpm.
Stumbles under acceleration. Feels like its missing.

My car is mostly stock but I put 24lbs injectors cause I have to replaced the old one and I thaugh thats gonna be a good idea to upgrade to a bit higher. After all I found my car less powerfull and burn out the o2 sensors, so I changed the o2 and the MAF sensor (BBK 24lbs pre-set). Power is back but the car won't run great on idle or when is got no load. I've been chassing the problem for a while but I need Help.

Thanks

J-F
Click to expand...

check the "surge idle checklist" made by jrichker. All your answers are there.

I had three Doritos Tacos for lunch today. Damn they were good.
 

Jean-Francois

New Member
May 23, 2013
6
0
1
Victoria
May 23, 2013
#4
  • May 23, 2013
  • #4
No code
 

Jean-Francois

New Member
May 23, 2013
6
0
1
Victoria
May 23, 2013
#5
  • May 23, 2013
  • #5
I look for codes and nothing than I re-adjust the TPS at .9 volts and than reset the computer. No change at all.
 

boostfrk

10 Year Member
Aug 30, 2011
712
69
59
Colorado
May 23, 2013
#6
  • May 23, 2013
  • #6
Go through the surging idle checklist as mikestang suggested.

http://www.stangnet.com/mustang-forums/threads/help-me-create-the-surging-idle-checklist.698148/
 

Jean-Francois

New Member
May 23, 2013
6
0
1
Victoria
May 23, 2013
#7
  • May 23, 2013
  • #7
Thanks I'll try it.
 
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