How can i tell if an injector is bad

Discussion in 'Trucks [ Eighteen Wheelers ]' started by san45bar, Feb 24, 2012.

  1. san45bar

    san45bar Light Load Member

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    I'm looking at a 96 freightliner and the guy is saying it has a blown injector and he doesn't want to get it repaired because he got it in a trade and with a kid who thought he could drive it as a farm truck with no tag or insurance or 2209 and etc lol thats another story. But he said he will give me a great price just to help me out, even though he is selling it to me for a cheap price i would like to purchase a quality truck that i can put to work asap..
     
  2. Kansas

    Kansas Road Train Member

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    Detroit engine or what?
     
  3. san45bar

    san45bar Light Load Member

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  4. Shaggy76

    Shaggy76 Heavy Load Member

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    Use a scanner and do an injector run out test. If one is unavailable, pull the harness one by one. If there is no difference in the engine when you pull the harnees, injector is bad or not getting voltage (presuming a HEUI or EUI injector). You can also break the fuel line down for each injector. If you do that and there is a "pop" or knock, injector is good, but cylinder is bad.

    Best solution after all of this is to pull the injector and inspect it. It could be something as simple as a $5 spring from you injector shop. Other option is to have a pop test done on the injector.

    It helps to know the engine for more specific steps.
     
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  5. Mr. Haney

    Mr. Haney Road Train Member

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    Walk away. The dealer could be hiding a much more serious problem with the engine. Unless he's willing to allow you to take it to a CAT dealer for the diagnostics beforehand to determine the cause of the problem, I'd run from it.
     
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  6. Smellfunny

    Smellfunny Medium Load Member

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    I would also want it checked out by some one else or walk away. You could have serious issues or it could just be an injector. Better to be safe than sorry. You could have a damaged camshaft or who knows.
     
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  7. Heavyd

    Heavyd Road Train Member

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    Walk away, this truck is 16+ years old.
     
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  8. Reddevil

    Reddevil Bobtail Member

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    16 Yrs ? just walk away buddy.. with this economy u can buy a better quality truck out there..GL
     
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  9. Shaggy76

    Shaggy76 Heavy Load Member

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    I also suggest that if you are wanting it for a classic truck or collector truck, take it to a CAT shop for the engine, or the local Freightliner. Have them do a 49 point inspection on it (which is a checkout of the entire truck including a engine scan) and ask for a oil sample, but do not change oil, filters, or grease. They usually run about $60 in my area for a inspection only. They will tell you everything wrong with it and then you can bargain lower on it. If they will not let your own guy work on it, it is best to walk away. They might have pulled the injecot and found a cam lobe worn off do to the injector getting seized (HEUI do this a lot) and is trying to get more from the truck. Cams are rather pricey and need a full overhaul of the engine, whics makes the truck worthless.

    Now on the other hand, if only an injecotr, you can knosk $3 - 4k off the price, get an injector and overhead done with full oil change service for under $1k. Options are yours and good luck on your potential purchase.