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Spark Knock?

 
groovygroveone
New User
Posts: 39
Joined: 03/12
Posted: 03/26/12 06:50 AM

What causes a spark knock?
How do you fix a spark knock?
I built a 5.0 fuel injected. The engine is bored .040 over. I put the engine in a 97 Mustang. Everything works well,but have a Hellava spark knock. I'm not using an egr valve,or the vacuum system for the 5.0's. Does anyone have any idea,what I need to do,to stop the spark knock? I can't believe that no one,has any ideas. And you call yourself a Ford person,or Mustang Enthusiast. Come on person,I need help.  

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waynep7122
User
Posts: 194
Joined: 02/10
Posted: 03/26/12 10:34 AM

have you verified that the timing is actually advancing???

with the EGR disconnected.. and a factory tune in the computer.. there will be more oxygen content in the intake air than the system realizes there is .. so it will be lean...  the combustion temp will also be higher because of the increased oxygen level..  EGR flow contains less than 10% oxygen.. where fresh air contains 21%..

were you able to set the timing as i described on the other post????   and what happens if you retard the timing ever so slightly???

do you have an adjustable fuel pressure regulator.. to boost the fuel rail pressure slightly???  causing the injectors to spray slightly more fuel with the same injector pulse..

did you print the 4 wiring diagrams for the  95 5.0 i posted???  and taped them together??

just curious.. i am looking at the 4 pages i taped together..  do you have a 60 pin computer connector or a 80 pin or a 104 pin connector...  

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groovygroveone
New User
Posts: 39
Joined: 03/12
Posted: 03/26/12 04:14 PM

#1- NO,Everytime I try to set the timing,I get between 12/14 deg. She stalls out!
#2- I am going to find all the stuff I need to put the EGR valve and the
vacuum system back on it. It's going to take sometime to roundup everything..I do not have an adjustable fuel regulator. Just factory with vacuum!
The computer I have is a 60 pin. I even ordered a new rebuilt to factory spec.and it didn't even change the engine running. The only thing I have done is regap the plugs,which helped some,Then I filled it up with Premeium gas,it did some..There should be a way that I can get this engine to run without all the extra junk on it.
I did it with my carburated 302 in my pickup. I feel I can with the fuel injected.
My mine is so fatigued out,I can't even think straight. One thing I need to get straight is the timing.Once I get that fixed,I feel I can get it like I want.I'm trying to think positive.I appreciate any help I can get at this point.  

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waynep7122
User
Posts: 194
Joined: 02/10
Posted: 03/26/12 05:47 PM

so when you back the timing down to 12/14 degrees it stalls out...

so it won't run below that...

unplug the idle air control valve...    does the engine idle at all.?????? or do you have to hold the throttle open to keep it running...

there should be a way to adjust the idle speed with the idle air control unplugged .. a throttle stop screw..  

with the spout unplugged. .



here are some instructions for setting the base idle...


It seems that many people have trouble with the way their 5.0 Mustang idles. Symptoms are usually a stumbling or rough idle which may be the result of modifications, or any number of other factors that may contribute to the problem. Clogged Emissions Gas Recirculation (EGR) Valves or Idle Air Bypass (IAB) solenoids are often to blame. A bad Throttle Position Sensor (TPS) will cause the engine to “hunt” for a proper idle setting. If you are experiencing idle problems first check the IAB. If it has large amounts of carbon deposits in it you may need to clean it using regular carburetor cleaner. You will have to remove it to do this, DO NOT clean it while it is on the car! If you have checked to make sure that your EGR, IAB, and TPS are clean and properly set and you are still experiencing problems try the following:

1. Clear the EEC-IV’s idle memory by disconnecting the battery for 20+ minutes.?

2. Disconnect the Idle air bypass solonoid

3. Reconnect battery?

4. Start engine and set idle speed to desired RPM with stop screw on throttle body (900 rpm works great with E303 or larger cam)

95Mustang50throttlebodybaseidlescrew

5. Turn off engine and reconnect the air bypass solenoid*Optional — set TPS to 0.90 - 0.95 volts (Do not exceed 1.0 volts MAKE SURE!) Use a digital volt meter!?

6. Start engine and let it idle for 2 minutes with no accessories on.

?7. Turn off engine for two minutes

?8. Start engine again and run for 2 minutes with every accessory turned on.?

9. Turn engine off again. Your computer should have now re-learned the new idle settings. This procedure assumes that you have a clean IAB valve. If it is carboned up then you may need to remove it and clean it with carburetor cleaner.

F.Y.I.:?For people that dont know you have to take off the neg. battery cable first and always put it back on last when disconecting both battery cables.



you will need to set the idle speed high enough with the idle air unplugged to allow you to set the timing spec for a 95 5.0...  

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groovygroveone
New User
Posts: 39
Joined: 03/12
Posted: 03/26/12 06:28 PM

I have printed these instruction.I will follow to a tee. Some of these things I have done before ,but there A couple I have never done before.TPS voltage adjustment for one.Wouldn't know where to begin!!.Or even adjust the fast idle screw!!( I do know where thats at!).....I have one question ,I don't know if you can give me the answer I'm looking for.OK<here goes.Why does a spark knockstart as soon as you start the engine? I thought it would take up too 5 min.s or so!. As soon as I start the engine the kknocking begins.I'm using APP25 plugs,should I use a lower grade of plug?  

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waynep7122
User
Posts: 194
Joined: 02/10
Posted: 03/27/12 03:07 AM

the spark knock is because you have the timing TOO FAR ADVANCED more than likely..

the computer needs to have the BASE timing perfect ....  as it knows just how far on a stock motor it can advance it..


perhaps this might help..

it still does not describe setting base idle...

http://www.youtube.com/watch?v=G5QKEJtevBw  

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waynep7122
User
Posts: 194
Joined: 02/10
Posted: 03/27/12 03:26 AM

Open the hood and disconnect the battery. Remove the negative terminal cable from the battery first, and then remove the positive terminal cable. Leave both cables off of the battery for at least 30 minutes.

2
Locate the Idle Air Control (IAC) module on the throttle body and disconnect it. Reconnect the terminal cables to the battery and start the engine.


3
Locate the stop screw at the bottom of the throttle body and use a screwdriver to adjust the idle rpm. Turn off the engine and reconnect the IAC module.

4
Start the engine again, with all accessories including the radio, A/C and lights off. Allow the engine to run for two minutes. Turn the engine off and wait for two minutes.

5
Start the engine once more, this time with all accessories on. Allow the vehicle to idle for two minutes and turn the engine off.


this image is larger than you can see... more to the right...

0900C152800727d6  

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