My Mustang Has No Power !!!!!

Discussion in 'Fox 5.0 Mustang Tech' started by dmitch28, May 3, 2013.

  1. I have a 92 mustang that i just installed a all stock motor in. It starts and runs good but when i hit the gas it feels like the car is taking off in fifth gear with a manual trans , but i have and aod installed. Also the new high flow cats i installed turned red hot. Please help
  2. Have you pulled the ECU codes?
  3. Try advancing the distributor. I've dealt with similar problems before and that's all it was. Mine ended up running 35* initial and 50* total advance.
  4. Do a full tuneup - spark plugs, spark plug wires, distributor cap, rotor, fuel filter, air filter and an oil change. Plan to do it all at once so that you can notice any difference in performance. This will not be a cheap venture, but the results will be worth time money and labor.

    Buy, beg or borrow a timing light to set the timing. You'll never get it set correctly without one.
    Setting the timing:
    Paint the mark on the harmonic balancer with paint -choose 10 degrees BTC or 14 degrees BTC or something else if you have NO2 or other power adder. I try to paint TDC red, 10 degrees BTC white and 14 degrees BTC blue.

    10 degrees BTC is towards the drivers side marks.

    Note: setting the timing beyond the 10 degree mark will give you a little more low speed acceleration. BUT you will need to run 93 octane to avoid pinging and engine damage. Pinging is very hard to hear at full throttle, so it could be present and you would not hear it.

    Simplified diagram of what it looks like. Not all the marks are shown for ease of viewing.

    ATC ' ' ' ' ' ' ' ' ' '!' ' ' ' ' ' ' ' ' ' BTC
    ---------------- > Direction of Rotation as viewed standing in front of the engine.

    The ' is 2 degrees.
    The ! is TDC
    The ' is 10 degrees BTC
    Set the timing 5 marks BTC. Or if you prefer, 5 marks towards the driver's side to get 10 degrees.

    To get 14 degrees, set it 7 marks BTC. Or if you prefer, 7 marks towards the driver's side to get 14 degrees.

    The paint marks you make are your friends if you do it correctly. They are much easier to see that the marks machined into the harmonic balancer hub.

    At this point hook up all the wires, get out the timing light. Connect timing light up to battery & #1 spark plug. Then start the engine.

    Remove the SPOUT connector (do a search if you want a picture of the SPOUT connector) It is the 2 pin rectangular plug on the distributor wiring harness. Only the EFI Mustang engines have a SPOUT. If yours is not EFI, check for a SPOUT: if you don’t find one, skip any instructions regarding the SPOUT
    Warning: there are only two places the SPOUT should be when you time the engine. The first place is in your pocket while you are setting the timing and the second is back in the harness when you finish. The little bugger is too easy to lose and too hard to find a replacement.

    Start engine, loosen distributor hold down with a 1/2" universal socket. Shine the timing light on the marks and turn the distributor until the mark lines up with the edge of the timing pointer. Tighten down the distributor hold down bolt, Replace the SPOUT connector and you are done.

    The HO firing order is 1-3-7-2-6-5-4-8.
    Non HO firing order is 1-5-4-2-6-3-7-8

    If you still have problems after the tune up & timing adjustment, dump the codes.
    Dump the codes: Codes may be present even if the Check Engine Light (CEL) isn't on.

    Dumping the computer diagnostic codes on 86-95 Mustangs

    Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

    Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

    Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

    Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

    Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
    Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.



    If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.


    The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

    89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.


    The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

    WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

    What to expect:
    You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

    Some codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

    Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off, and clutch (if present) is pressed to the floor, and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

    Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

    Your 86-88 5.0 won't have a working Check Engine Light, so you'll need a test light.
    See AutoZone Part Number: 25886 , $10

    Alternate methods:
    For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

    Or for a nicer scanner see Equus - Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30-$36.
  5. Sounds like you are getting excess fuel and the cat is trying to burn it off, is the car running rich ? Check to make sure your fuel pressure regulator diaphram hasn't ruptured and is sucking gas. Pull the vacuum line off and see if the line is full of fuel.
  6. Bad flux capacitor :)
  7. I have not pulled any codes but i will do it tomorrow. Thank you very much !
  8. I advance the timing but it stayed the same. Thanks for your help
  9. Thank you very much for all the info
  10. yes the car is running rich, I will check it out tomorrow. Thanks
  11. follow the info from jrichkter and report back. Remember when you adjust the timing it needs to be done with the spout connector out, and then replace it when done
  12. Also when you pull the codes, the codes come in sets of two like, 45, 12, etc (if you have a fox mustang). 94 - 95 (I think, have sets of three 543, etc). When you are pulling the codes make sure the engine is warmed up. First do key on, engine off, it will give you some codes then it will wait a few seconds then give you a single one (1) to tell you it is now pulling codes from the ECU's memory. Then turn the key on, engine on and do the same (except it will not pull from memory.)
  13. Thanks for all your help it ended up being bad spark plugs and the gap was incorrect
  14. Thanks for all your help fords2live it ended up being bad spark plugs and the gap was incorrect
  15. Big thanks to you jricher all your help it ended up being bad spark plugs and the gap was incorrect

  16. Thanks BlackGT89 for all your help it ended up being bad spark plugs and the gap was incorrect
  17. Thanks madspped for all your help it ended up being bad spark plugs and the gap was incorrect
  18. all good then?