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Engine No power after idle

  • Thread starter Thread starter JustinTilley86
  • Start date Start date Aug 10, 2024
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89ripper

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Aug 11, 2024
#21
  • Aug 11, 2024
  • #21
JustinTilley86 said:
Normally, I would not do that, but this thing is killing me
Click to expand...
I understand, just made for an extra variable to be thrown in. You know, going off of Aero's post a bad ecu could be the source of a lot of problems. I replaced mine with one from ecu exchange and 100% made a difference. One of the traces on the board was burnt up.
 
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J

JustinTilley86

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Aug 14, 2024
#22
  • Aug 14, 2024
  • #22
AeroCoupe said:
We have seen folks replace the capacitors and the ECU still not function 100%. You may get the point that sending the ECU for repair may be something you want to consider.

Ford Mustang 5.0 A9L A9P C3W A3M X3Z ECU Repair Service

Ford Mustang 5.0 A9L A9P C3W A3M X3Z ECUEngine Computer Repair ServicePlease fill out the R&R form here once you've placed your order.A Trusted Product with LIFETIME WARRANTY QUICK TURN AROUND TIMEDomestic and International Shipping available! Our Team is Available Monday - Friday 9am to 5pm...
www.theecuexchange.com
Click to expand...
I’ve tested the whole computer completely. Literally every single circuit and to add I have 2 others from older cars. I feel pretty confident it’s not in the computer.
 
J

JustinTilley86

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Aug 14, 2024
#23
  • Aug 14, 2024
  • #23
General karthief said:
If it was/is running rich it would give you a code
If it had a vacuum leak it would code lean.
Just think'n out loud
Click to expand...
I blocked every vacuum line and did a smoke test. I did it once from a cold engine to a fully warmed up engine. Haha that’s why this thing is killing me.
 

nickyb

I gotta say i never painted my nuts, Never Ever
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Aug 14, 2024
#24
  • Aug 14, 2024
  • #24
Keep going, you know you'll find it the last place you look. Now getting to that last place,well that's the part that kills ya.
 

General karthief

wonder how much it would cost to ship you a pair
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#25
  • Aug 14, 2024
  • #25
JustinTilley86 said:
I blocked every vacuum line and did a smoke test. I did it once from a cold engine to a fully warmed up engine. Haha that’s why this thing is killing me.
Click to expand...
Smoke test will not reveal a bad FPR, pull the vacuum line off and smell it.
A leaking diaphragm will cause fuel to be sucked into the intake and run 'fat'. Especially at idle.
 
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JustinTilley86

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Aug 16, 2024
#26
  • Aug 16, 2024
  • #26
General karthief said:
Smoke test will not reveal a bad FPR, pull the vacuum line off and smell it.
A leaking diaphragm will cause fuel to be sucked into the intake and run 'fat'. Especially at idle.
Click to expand...
The FPR isn't bad. I most likely having a wiring issue. Even if the FPR was bad for it to smoke black the way it does it would have to have a massive hole in the diaphragm. I had a issue with an injector at first not get the signal for the eec so I ran a overlay to see if it would clear up and it did a little. The issue I face now is it revs up and idles good but any kind of load shuts the car down and will not start back unless to hold WOT to tell the eec the car is flooded.
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#27
  • Aug 16, 2024
  • #27
I reread this whole thread and it’s minor but the fuel pressure caught my eye. Fuel pressure should be 39 psi at idle with the vacuum line disconnected. With it connected it will drop and as the rpm’s come up it will increase with demand. 39 psi at idle with the vacuum connected is not the factory setting. I don’t think this is the issue but it’s not helping.

ECU’s - unless you can confirm the other ECU’s you are trying are good then for me they are suspect as well. Without a breakout box testing them by hand is difficult at best. Other thing is I don’t know how you are testing the chips. What year Mustangs are the older ones out of and what letter designation are they?

Its just odd how the car is running pig rich and you are not getting a CEL for the O2 sensors.

Also, make sure the BAP sensor does not have a vacuum line on it.
 
Last edited: Aug 16, 2024
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JustinTilley86

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Aug 24, 2024
#28
  • Aug 24, 2024
  • #28
I thought I would add this quick update. I’m not even sure why I didn’t check this first. The harmonic balancer spun so it was out of time this whole entire time. I’m waiting for a new one to show up and hopefully everything will be fixed.
 
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AeroCoupe

lube between the nut and the face. I know my lubes
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#29
  • Aug 24, 2024
  • #29
That will for sure cause issues. Be sure to let us know if that is the fix or not.
 
J

JustinTilley86

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Aug 24, 2024
#30
  • Aug 24, 2024
  • #30
Will do!
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#31
  • Aug 24, 2024
  • #31
Thats one thing i always forget to mention when giving fox advice. I've been through that more than a few times. If the rubber is bulging at all i replace them. Glad you found that issue.
 
F

Flyboy60

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#32
  • Sep 22, 2024
  • #32
Hello - Bump
 

Noobz347

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#33
  • Sep 22, 2024
  • #33
JustinTilley86 said:
I thought I would add this quick update. I’m not even sure why I didn’t check this first. The harmonic balancer spun so it was out of time this whole entire time. I’m waiting for a new one to show up and hopefully everything will be fixed.
Click to expand...
 
F

Flyboy60

20+ Year Stangneter
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#34
  • Sep 23, 2024
  • #34
Noobz347 said:
Click to expand...
Self Termination ?
 

General karthief

wonder how much it would cost to ship you a pair
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#35
  • Sep 23, 2024
  • #35
Flyboy60 said:
Self Termination ?
Click to expand...
instructional imogi
 
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