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how do u find out if injecters are bad on 1989 2.8 v6 z24 because i have looked at ever thing and the car will still not start i have spark, timing is good, computer is good, battery good, alt. good ever thing is but it will still not start if u have any other ideas about what it could be besides the injecter please tell me :roll:

i drove it the day before and i worked fine and the nexted day it would not start. i had to fix the cable for the speed the day before but that should have nothin to do with it not working or starting.
 

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does the car turn over? when you turn the key what sound is made?
 

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get a digital multimeter. then, find the harness at the back of the pklenum. it will have 4 wires. i cant remember which colors for which banks, but just test the first wire against the second, third and forth. if its an open loop its the wrong wire. one of the other 3 will give a resistance. It should read 4.2 - 4.6 Ohms. Then test the other 2 wires and they should also read 4.2 - 4.6 Ohms. if one has a lower or higher resistance by (usually lower) than test the resistance of the injectors. they should be 12.4 ohms each. if any are lower than 11.8 Ohms replace that injector. try to do it while there still warm because the temp will alter them slightly.
 

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If Bighunter has spark then I doubt its a bad crank sensor.

You should determine if you have 40 psi of fuel pressure at the fuel rail before you blame the injectors. Get a fuel pressure tester if you dont have one.

The only way the injectors could cause a no start is if one is shorted. The ECM will not fire any injectors if one is drawing too many amps. Burn is right on how to measure resistance. One bank of injectors is the outside pair of wires on the connector and the other bank is the center pair if I remember right.

Another way to test if its a fuel problem is to spray some starting fluid into the intake while the starter is cranking. If it trys to run then you know its a fuel problem of some sort.

Good Luck
 

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hdunbar said:
If Bighunter has spark then I doubt its a bad crank sensor.

You should determine if you have 40 psi of fuel pressure at the fuel rail before you blame the injectors. Get a fuel pressure tester if you dont have one.

The only way the injectors could cause a no start is if one is shorted. The ECM will not fire any injectors if one is drawing too many amps. Burn is right on how to measure resistance. One bank of injectors is the outside pair of wires on the connector and the other bank is the center pair if I remember right.

Another way to test if its a fuel problem is to spray some starting fluid into the intake while the starter is cranking. If it trys to run then you know its a fuel problem of some sort.

Good Luck
im assuming to get to the injectors wires you have to take the plenum off??
i have the same problem with my car not starting, and ive replace pump, cps, module, coils, i have 43psi at the rail, if i put gas in the cylinder it will run on it til there is no more, therefore there is spark. so should i check the injectors next??
 

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burn said:
get a digital multimeter. then, find the harness at the back of the pklenum. it will have 4 wires. i cant remember which colors for which banks, but just test the first wire against the second, third and forth. if its an open loop its the wrong wire. one of the other 3 will give a resistance. It should read 4.2 - 4.6 Ohms. Then test the other 2 wires and they should also read 4.2 - 4.6 Ohms. if one has a lower or higher resistance by (usually lower) than test the resistance of the injectors. they should be 12.4 ohms each. if any are lower than 11.8 Ohms replace that injector. try to do it while there still warm because the temp will alter them slightly.
I agree. This is the best and the most accurate way to test injectors. :wink:
 

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no, you dont have to take the plenum off, just look at the back side of the plenum. you will see a harness of 4 wires bolted to the intake plenum. those 4 wires are to the injectors. 2 wires go to each set of 3 injectors.
 

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burn said:
no, you dont have to take the plenum off, just look at the back side of the plenum. you will see a harness of 4 wires bolted to the intake plenum. those 4 wires are to the injectors. 2 wires go to each set of 3 injectors.
thanks man :D
 

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burn said:
get a digital multimeter. then, find the harness at the back of the pklenum. it will have 4 wires. i cant remember which colors for which banks, but just test the first wire against the second, third and forth. if its an open loop its the wrong wire. one of the other 3 will give a resistance. It should read 4.2 - 4.6 Ohms. Then test the other 2 wires and they should also read 4.2 - 4.6 Ohms. if one has a lower or higher resistance by (usually lower) than test the resistance of the injectors. they should be 12.4 ohms each. if any are lower than 11.8 Ohms replace that injector. try to do it while there still warm because the temp will alter them slightly.
Like That :)
 

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burn said:
get a digital multimeter. then, find the harness at the back of the pklenum. it will have 4 wires. i cant remember which colors for which banks, but just test the first wire against the second, third and forth. if its an open loop its the wrong wire. one of the other 3 will give a resistance. It should read 4.2 - 4.6 Ohms. Then test the other 2 wires and they should also read 4.2 - 4.6 Ohms. if one has a lower or higher resistance by (usually lower) than test the resistance of the injectors. they should be 12.4 ohms each. if any are lower than 11.8 Ohms replace that injector. try to do it while there still warm because the temp will alter them slightly.
Is this the same for all motors?

I've got a 2.2 L.
 

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I believe that it should be close. But different injectors have different Ohms. It would be best to consult a book on your car. It will let you know exactly what range your injectors should be withiin. But the method of checking them is the same.
 
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