Pull the Codes from the ECU. Also check all fuses.
Heres how you can pull the codes.
DIY KOEO/KOER/Cylinder Balance Self-Test Procedure
Heres how you can pull the codes.
DIY KOEO/KOER/Cylinder Balance Self-Test Procedure
1989 Mustang GT Check Engine!
So here it goes, tonight my friend was trying to install my Pioneer cd player, he had no idea really what he was doing then accidentally touched a power wire on the side of the metal deck which made a big spark then no power to the cd player. I then went to turn my car back on to see if we had power and my car started very rough, idle shot up to 2500-3000 rpm then came down to the normal 700, also the check engine light came on as well, I shut the car off a couple of times and restarted to it doing the same thing. After leaving the car awhile I went to re start it and it would not start, kept cranking and cranking and not fire. I finally kept the gas to the floor and then it started, idle shot up to 1500 and went down to the normal 700 ish, then went down to 600 then to 500 then back to 600. I then drove the car home to find that it seems like it has a lack of power? 1st still seems to pull the same but 2nd not as good? I am very very confused to what any of this could be, TPS, when the wire grounded could it have ruined something in my ECU? Please help ASAP! Thank you very much..
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Pull the Codes from the ECU. Also check all fuses.
Heres how you can pull the codes.
DIY KOEO/KOER/Cylinder Balance Self-Test Procedure
I checked all the fuses and everything looks good, I will be throwing on a code reader tomorrow at the shop to check to see what it says. Also during the deck install the ignition was turned on quite a few times, which intern the fuel pump was on quite a bit... I went out today and checked a few things and once again it didn't want to start, had to floor the gas pedal to even get it to start for me then after that it was starting fine....
Just got back from the shop, the car will not throw any codes, the shop did a ton of tests that took about 30-40 minutes, not one brought up why the check engine light is on. Today it feels as though the car is running better with a lot more go, but the idle is still loping. When the stereo wires grounded could it have effected the tps or anything like that at all? Also when I use to start the car it would rev up to about 1500 rpm then come down like most vehicles do, now it starts instantly but does not rev up, almost seeming like it bogs? Thanks for the help!!
Here's is what you can try, in the diagram below, jump the STI Terminal(small grey one) straight to a good ground, Then hook up a test light with the alligator clip side to the Positive side of the Battery and the probe side, to the STO terminal. Turn the Key to the on Postion(Not Running) and see what codes flash, If any.
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If the CEL light is on, there's a code. Try what he just said and see what you get.
Hopefully your friend didn't fry the computer, all it takes is a power surge like that and it'll be cooked. Don't let him work on your car anymore. :so
Hopefully your friend didn't fry the computer, all it takes is a power surge like that and it'll be cooked. Don't let him work on your car anymore. :so
I have a 93 5.0 maf mustang computer, if you need one.
If the ECM winds up being fried at the SIGRTN, you can fix it your self. Ill help you, but need to make sure first. The codes will tell you that.
Here's is what you can try, in the diagram below, jump the STI Terminal(small grey one) straight to a good ground, Then hook up a test light with the alligator clip side to the Positive side of the Battery and the probe side, to the STO terminal. Turn the Key to the on Postion(Not Running) and see what codes flash, If any.
Just drove the car to Wal Mart to pick up a test light, ran great other then the 500 then to 700 then to 600 rpm range lol. I jumped the STI with a piece of 14g wire to a ground then bolted it down to make sure it stayed grounded, then I put the test light gator clip on the pos cable and the probe into the STO spot, the light just stayed on, did not flash at all.
Nope, just had the key in the on position where the fuel pump turns on, and that is it.And the car was not running?
Sound like you have a problem in some wiring for the Test output plug. Do you have a Digital Volt meter?
No, I do not have a volt meter.... This seems like it is getting worse and worse so farSound like you have a problem in some wiring for the Test output plug. Do you have a Digital Volt meter?
Do you feel comfortable taking the Computer apart? Just need to take the Metal case off, and inspect the ECM board for and burnt spots. If you had a Digital Volt meter, you could check the resistance on the STI wire at the ECM connector PIN 48 with the ECM unhooked.
Do you feel comfortable taking the Computer apart? Just need to take the Metal case off, and inspect the ECM board for and burnt spots. If you had a Digital Volt meter, you could check the resistance on the STI wire at the ECM connector PIN 48 with the ECM unhooked.
I will check with the shop about using there volt meter sometime.
So I went for a drive tonight, running good minus the CEI. I then brought it home and thought I would try to get a code one last time. It worked! It gave me a code 22 as in the light blinked 2 times then paused, then another 2. So now time for the good news/bad.. what is a code 22? MAP/Barometric Pressure Sensor????
Run both the KOEO and KOER
And this can be done with the test light? Sorry, when it comes to electrical I am clueless. When it comes to carb's count me in
haha.
The test you ran to get the code 22. You can leave the test light hooked up the way you got the code. Turn key on but don't start it. Then count the codes that flash. Should be 2 digit codes. Then turn car off, crank the car up. And count the codes again. The second test will take a few minute before the codes flash. As its testing the sensors and soforth.
The test you ran to get the code 22. You can leave the test light hooked up the way you got the code. Turn key on but don't start it. Then count the codes that flash. Should be 2 digit codes. Then turn car off, crank the car up. And count the codes again. The second test will take a few minute before the codes flash. As its testing the sensors and soforth.
Alright, will do that tonight or tomorrow sometime, now as the code 22 it gave me I did some reading and that explains the rough idle and so on. Are you thinking there might be more or?...
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