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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

1990 5.0 Rough Idle Problem

  • Thread starter Thread starter TS1992
  • Start date Start date Jul 11, 2015
T

TS1992

New Member
Jul 11, 2015
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0
1
Jul 11, 2015
#1
  • Jul 11, 2015
  • #1
I've got a rough idle problem and I've tried researching and replacing the most common issues.

I have replaced these:

-Fuel injectors
-EGR valve
-Spark plugs
-TPS
-IAC
-PCV


I'm at a loss and hoping someone has suggestions for something else to try. The only thing I haven't tried just yet is replacing the MAF but I'd like to see if there are other possibilities first.
 

Grabbin' Asphalt

10 Year Member
Jun 10, 2013
2,029
310
124
Atlanta, Ga
Jul 12, 2015
#2
  • Jul 12, 2015
  • #2
Pull codes yet??
I imagine if you replaced the tps it needs to be recalibrated as well, ...you did that too already??
Wait on the maf, too many things to check first before $$$ is dumped.

*Btw I'm showing a lot of Love today with your Newbe status
lotta' new guys have it sitting a while because of the amount of info on old threads ...Lol
Always state what type of status the car is in as far as upgrades on parts or completely stock etc, helps everyone that even thinks about tossing in advice.
 
Last edited: Jul 12, 2015

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
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Jul 12, 2015
#3
  • Jul 12, 2015
  • #3
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.

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 159,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
T

TS1992

New Member
Jul 11, 2015
3
0
1
Jul 12, 2015
#4
  • Jul 12, 2015
  • #4
Thanks for replying!

TPS was recalibrated and no codes pulled yet. I can't get it to a place with a reader at this point.

It is all stock. Trying to hold off on the MAF even though it seems to be the last most common issue.
 
T

TS1992

New Member
Jul 11, 2015
3
0
1
Jul 12, 2015
#5
  • Jul 12, 2015
  • #5
jrichker said:
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.

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 159,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
Click to expand...

I actually found that last night! Went through it with my husband and he's going to be looking at a few of the things on the list that he hasn't done already. Very helpful, thank you!
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
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Dublin GA
Jul 12, 2015
#6
  • Jul 12, 2015
  • #6
Please let us know what you find.

User feedback helps improve the checklist and refine the procedures.
 
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