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P1131 Code and Rattle Under Throttle

  • Thread starter Thread starter Devon27
  • Start date Start date Jun 24, 2021
  • Tags Tags
    bad o2 sensors engine rattle p1131 preognition
D

Devon27

New Member
Dec 6, 2019
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Virginia
Jun 24, 2021
#1
  • Jun 24, 2021
  • #1
So a couple weeks ago I noticed my 00 GT would rattle at around 3000 rpm in certain gears after it warmed up. It was a rattle faint sound coming from the motor that I could feel vibrating the gas petal pretty aggressively. Sounds almost like an exhaust leak and I assumed it was pre-ignition. I did some investigation into the ignition system and didn’t find any clues. I then concluded I had filled up with a bad tank of gas so I ran some cleaner and it went away for a few days.

It is back now and today while driving I got the P1131 code. I assume the issues are related. I’m going to check the usuals, the 02 sensors, vacuum lines, fuel injectors and MAF. Any pointers into what to look into first given the pre-ignition like symptoms? On the first day I noticed it getting real bad I experienced a loss of power on takeoff as well but that went away after after running fuel system cleaner. Could bad O2 or MAF sensors be causing all that?
 
D

Devon27

New Member
Dec 6, 2019
12
0
1
Virginia
Jun 24, 2021
#2
  • Jun 24, 2021
  • #2
Devon27 said:
So a couple weeks ago I noticed my 00 GT would rattle at around 3000 rpm in certain gears after it warmed up. It was a rattle faint sound coming from the motor that I could feel vibrating the gas petal pretty aggressively. Sounds almost like an exhaust leak and I assumed it was pre-ignition. I did some investigation into the ignition system and didn’t find any clues. I then concluded I had filled up with a bad tank of gas so I ran some cleaner and it went away for a few days.

It is back now and today while driving I got the P1131 code. I assume the issues are related. I’m going to check the usuals, the 02 sensors, vacuum lines, fuel injectors and MAF. Any pointers into what to look into first given the pre-ignition like symptoms? On the first day I noticed it getting real bad I experienced a loss of power on takeoff as well but that went away after after running fuel system cleaner. Could bad O2 or MAF sensors be causing all that?
Click to expand...
Update: A few hours after the code showed up my car began to surge at idle. And it climbs up to 3000 rpm and hangs then goes down for a few seconds and repeats.
 
J

Jtotheayy

New Member
Feb 5, 2023
1
0
1
Feb 5, 2023
#3
  • Feb 5, 2023
  • #3
Devon27 said:
Update: A few hours after the code showed up my car began to surge at idle. And it climbs up to 3000 rpm and hangs then goes down for a few seconds and repeats.
Click to expand...
Hey, did you figure it out? I’m having the same exact issues and also got the P1131 code. Thinking im just going to change the o2 sensor, but did that solve your problem?
 
S

Shuttleman83

Active Member
Jun 30, 2019
239
13
28
USA
Feb 7, 2023
#4
  • Feb 7, 2023
  • #4
Hanging up high like that and then dropping and hanging back up is usually TPS. Just replace it and or the wiring to it.
 
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