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i think my injectors are going bad or something. my truck gets around 9mpg around town and i got about 14-15 mpg driving from new jersey to kentucky (65-70) not towing. it usually has a little black puff on startup and then goes away. also i notice the throttle hangs sometimes when i romp it fast and the truck keeps going for a little while. i ran some powerservice threw the tanks and i made no difference. its auto with 4.11 gears. any way i can find out for sure without pulling the injectors?
 

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i would have them tested.about 40 bucks each for the testing.check your oil,make sure you dont smell diesel in it.if you do there cracked.
 

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no. you can do a kill test with certain types of scanners. you can shut off each injector individually. if an injector is working correctly, when you kill it, the idle should drop 30-50rpm. if it is not working, you wont hear a noticable change. i havent actually done this, but i have had injector problems recently and this is what i was told to do. i think it is called a star scanner. i ended up just pulling them and sending them to don at f1 and its a good thing i did. i had two cracked nozzles i didnt know about.
 

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no. you can do a kill test with certain types of scanners. you can shut off each injector individually. if an injector is working correctly, when you kill it, the idle should drop 30-50rpm. if it is not working, you wont hear a noticable change. i havent actually done this, but i have had injector problems recently and this is what i was told to do. i think it is called a star scanner. i ended up just pulling them and sending them to don at f1 and its a good thing i did. i had two cracked nozzles i didnt know about.
whats the turnaround on them? i would like to do it but its mid winter and i need the truck because we are getting hammered with snow. :banghead:
 

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it all depends on how busy he is.

contacts

you have to go through one of these guys. you cant talk to don directly. i used source automotive. i like them so far.
 

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Throttle hang is normal on these CR's to keep the rail pressure in check. Don't gauge problems by that.

Your mileage is not good even with 4.11's. Should be a bit better than that.

There are 2 things you can do without pulling the injectors, run a return flow test and a cylinder contribution test. The return flow test will tell you if there is massive wear in the injector and you should get new bodies. The contribution test will tell you 1 or more cylinders are spraying too much fuel.

Without doing these 2 test your just guessing at the problem.

If the flow test or contribution test shows too much fuel don't bother getting them rebuilt, its not reliable. You will need new bodies and tips so ordering new injectors wiht either stock tips or an upgrade. There are numerous places to buy them, some cheaper than others.
 

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I had 1 go bad at about 40,000 miles. I was getting a miss at idle pretty easy to tell there was a problem. I keep wondering if I still have a problem as I'm only getting 11 to 12 mpg (hand calculated). My mpg got better with the 35s.
 

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Throttle hang is normal on these CR's to keep the rail pressure in check. Don't gauge problems by that.

Your mileage is not good even with 4.11's. Should be a bit better than that.

There are 2 things you can do without pulling the injectors, run a return flow test and a cylinder contribution test. The return flow test will tell you if there is massive wear in the injector and you should get new bodies. The contribution test will tell you 1 or more cylinders are spraying too much fuel.

Without doing these 2 test your just guessing at the problem.

If the flow test or contribution test shows too much fuel don't bother getting them rebuilt, its not reliable. You will need new bodies and tips so ordering new injectors wiht either stock tips or an upgrade. There are numerous places to buy them, some cheaper than others.
there is a vid on how do do the return flow test. it is the 4th vid down and min 4:39-6:00. click here figured this might be a little help if you didn't know what test that was.

bowz
 
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