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Discussion Starter #1
I am replacing my injectors this weekend. Was wondering if I should go ahead and just pull the cups aswell and clean those and replace the seals or if I should just leave them. Truck has 105K on the original injectors.
 

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I personally leave the cups alone as long as they didn't/don't break the bottom seal. But there are guys on here that change them more often than myself and may be more knowledgeable on that question. My thinking is, you take a slight risk of not getting a good seal (on the bottom) because of coolant, or anything to prevent the loctite from setting properly. Just not to sure of what the life of the top o-rings are.
 

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Discussion Starter #4
is it easy to tell before pulling out a cup if it was or is leaking or not sealed?
 

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Discussion Starter #5
Also I want to check the valve gaps. All I have to do basically is after I take out the injector and maybe the cup is look into the cylinder and make sure the piston is at the top of the compression and then check the valve gap for that cylinder right?
 

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I just did mine for the second time. Just under 300K miles. The R&R was going smoothly but the injector closest to the firewall on the driver's side (#8 I think) looked bad when we pulled it and the cup was full of junk. I decided to pull the cup and it needed replacing. Decided to replace all 8 since I plan at least another 200K on the truck. I would say as long as the cups don't come out and they look good, leave them be. Bought a cup and injector puller off ebay which made the job 100% easier.
 

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Discussion Starter #7
awesome thanks everyone. But when ya'll say "if the cups look good" you mean if inside where the injectors rests, that needs to be clean and you should b able to see the washer right?
 

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Discussion Starter #8
is there a DIY for the injector cups? With pics?
 

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Washer "should" come out with the old injector. Just want the inside of the cup to be free of any debris/carbon. With only 105k on the clock your cups should be good. Not sure on diy but you can always check youtube.
 
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