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  • 2005 - 2014 S-197 Mustang -General/Talk-
  • 2005 - 2009 Specific Tech

Please help. Failed computer?

  • Thread starter Thread starter MarathonPunner
  • Start date Start date Apr 28, 2019
M

MarathonPunner

New Member
Apr 28, 2019
5
0
1
Kansas
Apr 28, 2019
#1
  • Apr 28, 2019
  • #1
I just bought an 09 cs 2 weeks ago. Only had 27k miles. It had a Ford racing cai and magnaflow exhaust when I bought it. I noticed the engine bay was very clean and was worried someone may have pressure washed it but it seemed to run ok and no problems.

Flash forward to 3 days ago and the cel comes on but it was running fine . Get the code read and it was p0171/p0174 lean on both banks. I start it up to drive home and wouldn't idle worth a dang. Rpm is all over the place, stuttering, shuttering...

So I have done some work to resolve the issue and. Nothing is working. I am also now getting a ton of codes.

I cleaned and then replaced maf (ford)
New tps sensor
Cleaned tb
Fuel filter
Checked for vacuum leaks with propane
Cleaned/oiled air filter


Symptoms
Sometimes hard start like it's starved for fuel or out of time

Rough idle like it is out of time or misfiring

Stumble ad idle

Rpm raises and lowers all on it's own constantly

Codes
First time was lean banks

I had the codes read again just now at oreilly and was given the following:
P2112
P2110
P2107
P2104
P2008
P0223
P0122
P0020

I'm tearing my hair out here and all these codes indicate tps , throttle actuator, and timing issues. The dealership wontblet me bring car in until middle of the month and by then my "warranty" is up. They wont budge on that. They dont want to pay which is a shame. This isn't somenfly by night place.

So. What is going on?
 
M

MarathonPunner

New Member
Apr 28, 2019
5
0
1
Kansas
Apr 28, 2019
#2
  • Apr 28, 2019
  • #2
I just replaced the theottle body actuator and it didnt help.

Now when I start it my tire pressure monitoring system error light comes on.
 
M

MarathonPunner

New Member
Apr 28, 2019
5
0
1
Kansas
Apr 28, 2019
#3
  • Apr 28, 2019
  • #3
I just got done unplugging coils and injectors one at a time with car idling.

Idle didn't change much if at all with any of the injectors unplugged except maybe one or 2.

But with coil packs it was hit or miss. Unplug a coil and nothing happens. No change in idle.
Turn off car, restart, unplug same coil to repeat test and now the car nearly dies.

At one point it seemed only the back and front cylinders were firing.(4 total)

It seems the coils aren't firing on every cycle and that it is also inconsistent.

I now hear a plastic like grind or low squeak coming from one of the coils intermittently as well.
 
M

MarathonPunner

New Member
Apr 28, 2019
5
0
1
Kansas
Apr 28, 2019
#4
  • Apr 28, 2019
  • #4
I just checked the purge canister ad well and it is fine
 
M

MarathonPunner

New Member
Apr 28, 2019
5
0
1
Kansas
Apr 29, 2019
#5
  • Apr 29, 2019
  • #5
Ran a vacuum test
Had alternator checked
Both were good

Replaced cam sensor and crank sensor without muchnif any change
 
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