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Old August 4th, 2006, 09:32
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Biglead Biglead is offline
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Question Fuel injection problems

For a project, I purchased an 89 pioneer with really high mileage with the intention of making it in to a trail rig. Anyway the 300,000+ mile engine was replaced with a rebuilt long block from the local parts store which is working fine but I used the original fuel injection parts from the old motor. The motor has been working great for the last 10k but now I am noticing a hiss coming from the injector closest to the firewall when I start the engine on colder mornings. There are no fluids leaking from the injector and I can wiggle it to make the hiss go away. I know I need to replace them or have them rebuilt because they are pretty old. BUT I recently read a few articles on replacing the old ones with certain year Ford or later year XJ injectors and increasing the mileage a bit over stock. Something about a better spray increasing mileage and what not. Since the injectors are pretty expensive to replace I was wondering if anyone else has used other than stock replacements with any noticed improvement or am I better getting the correct ones for my make/model.
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Old August 4th, 2006, 09:53
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RichP RichP is offline
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Re: Fuel injection problems

I bought a set from fiveoh motor sports, replaced the stockers with them when the new jasper reman went in. Same milage...
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Old August 4th, 2006, 10:19
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langer1 langer1 is offline
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Re: Fuel injection problems

The hissing sound is a vacuum leak around the injector, not the injector.
You did replace the o-rings? One may have gotten nicked when you did.
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Old August 4th, 2006, 14:36
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Saudade Saudade is online now
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Re: Fuel injection problems

What Langer said about the leak x2. Most likely the end that goes into the head.

I bought a set on eBay that were from a Mustang. Got a set of 8 for about $50. I haven't notice any real mileage improvement over the long term. My throttle response did seem to improve. But then, my old injectors were pretty dirty.
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Old August 7th, 2006, 18:18
90cherk 90cherk is offline
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Re: Fuel injection problems

From my experience when my injectors started leaking I replaced with a pulled (not new and much cheaper) Bosch set purchased from five-o motor. Ended up having to replace one of those that for some reason was sticking open. Anyway after some other engine work now my mileage has gone up about 1mpg based on my highway driving which is better than the mileage I got when it was brand new 16 1/2 years ago.
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