Engine Power Loss, Not Sure Of The Problem.

Discussion in 'Fox 5.0 Mustang Tech' started by James.Little, Apr 26, 2013.


  1. jrichker

    jrichker StangNet's favorite TOOL SN Certified Technician Founding Member

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    Set the base idle according to the procedure I posted.

    The ECT is in the heater supply tube that comes out of the front tube on passenger side of the lower intake manifold. The upper manifold is facing the direction for a full size passenger car, but it is still the same manifold assembly.

    Click on the image to enlarge it....
    The ECT is item #30 in the picture. It screws into item#29, the heater feed tubing assembly


    [​IMG]

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  2. James.Little

    James.Little Member

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    well, you said to go ahead and to fix all errors before I set the base time. Should I just go ahead and set the time?

    also, thanks for all the help, you're awesome. Are you a engineer of some sort?

    So I looked again and the vacuum line from the EGR valve was broken, I haven't had time to fix it, but should that get rid of the ECT and EGR error codes?


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  3. James.Little

    James.Little Member

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    Okay I fixed the vacuum lines and replaced the plug wires with Ford Racing 9mm plug wires. Holy crap, I feel more power (keyword: feel) and it starts up with less hesitation (but it is still there) and it idles better than ever, right at about ~750-800 RPMs. Now I have noticed when I start her up, it hesitates but then it grabs (now without the gas pedal). Then if I shut her off and try again, I now have to use the gas pedal. Also it sill struggles in the higher RPMs. I haven't had the chance to fix my poorly done MAF swap job, but once finals are over I will give it a go. I don't think the inactive MAF sensor is the problem, since it has been this way for several months and I have just now seen the problem. I have a new cap and rotor on the way. I think I might pull codes again and see what it will give me.
  4. James.Little

    James.Little Member

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    I fixed it! I replaced the ECT and it fires right up!

    So to recap, the car was struggling to start, had a hard time in the mid-to upper RPMs. I replaced the fuel filter, plugs and plug wires. (I still have a cap and rotor on the way). The engine ran amazing after the minor tune up, but still struggled to start. First time I pulled the codes I had tons of problems, fixed everything (except for the MAF swap problems), found a broken vacuum line, fixed it, that didn't do anything noticeable. I cleaned the IAC valve and the Throttle body. Pulled the codes again, only codes I received where pertaining to the MAF swap stuff. Only struggled to start and ran like new. Found this post (http://forums.corral.net/forums/5-0-5-8-engine-tech/680934-starts-only-when-gas-pedal-pressed.html), went a bought a new ECT and it fixed the start problem.

    Thanks for all the help, you're all awesome!
  5. jrichker

    jrichker StangNet's favorite TOOL SN Certified Technician Founding Member

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    From the Cranks OK, but No Start Checklist for Fuel Injected Mustangs which was my first responce to your questions....

    Paragraph 6 E.) No start when hot - Press the throttle to the floor & try starting it if you get this far. If it starts, replace the ECT.


    The checklist has 99% of the fixes for cranks OK but no start. If you had followed it, you could have been driving sooner.

    The good news is that now that you have it fixed, you can enjoy driving your Mustang this spring and summer. :)
  6. James.Little

    James.Little Member

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    Sorry I didn't read that. I figured since I got it to start, I didn't need to read that part. I guess I should have at least read it to pick up clues. Also, I have been driving it around the whole time, I just had to keep the pedal on the floor when I started it up.

    Also, thank you for your time and help, there is no way I could have done this without your contribution. Yes, I love driving her around!

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