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Engine 90 Lx Rough Idle

  • Thread starter Thread starter BadFoxLX
  • Start date Start date Feb 27, 2014

BadFoxLX

New Member
Feb 24, 2014
2
0
2
Feb 27, 2014
#1
  • Feb 27, 2014
  • #1
What's up everyone,

I have a 1990 LX Convertible that I recently purchased for a project. It has 121k miles on it, and its not in perfect shape, but it runs strong. The problem I am having is I am idling around 600 rpm with small jumps in RPMs without touching the fuel pedal. I had a similar problem with my 89 GT and the TP Sensor fixed it.

Steps I Have Taken:

- Replaced MAF Meter & Sensor
- Replaced TPS
- Replaced Plugs & Wires
- Replaced thermostat with a 180, but the car still runs at 140 or a little higher.
- Replaced Brake Booster & Master Cylinder (had a vacuum leak)

Any suggestions on other steps I should take? My timing is currently set at 10BTDC. The car is mostly stock with a smog pump delete and CAI being the only exceptions. Throttle response does not seem to be where it should also. I plan on this car being a DD until I decide on what build to move forward with, so I want to get it running solid ASAP. Here is a pic because pics are cool. Lol.



Thanks in advance!
 

Grabbin' Asphalt

10 Year Member
Jun 10, 2013
2,029
310
124
Atlanta, Ga
Feb 28, 2014
#2
  • Feb 28, 2014
  • #2
Surging idle checklist coming up @jrichker
 

madspeed

Colonel Mustard
Founding Member
Nov 29, 1999
8,914
1,332
204
a van down by the river
Feb 28, 2014
#3
  • Feb 28, 2014
  • #3
You can find it here

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