causes for knock, not injectors
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causes for knock, not injectors
I just got done putting in injectors and the truck still knocks, has anybody ran into any thing else.
Anything to check into before I pull the engine.
7.3 f250 cc auto 2002
Anything to check into before I pull the engine.
7.3 f250 cc auto 2002
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Joined: Sep 2006
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From: NorCal
On the back of the fuel bowl. The upper left is pre filter. The lower right is post filter. I believe you need a 3/8" Allen to get them out.
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Cargo Master
Joined: Mar 2006
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From: Bend Oregon
Air in fuel as well, ford called it "cackle" but it always sounded like a knock to me. Have you done any of the in tank mods or a regulated return? When you replace all the injectors did you install all ADs or did you put an long lead injector in #8?
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Laughing Gas
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From: Dallas, Oregon
Take it out and drive it at 50-60 mph, then take your foot off the accelerator pedal. If the knock stops, it is injector-related, since the injectors quit firing in this situation.
I have an injector knock in #7 (passenger side rear cylinder) that remains despite replacing injectors, UVCH, high-pressure oil cross-connect, regulated fuel return, in-tank mods, careful inspection of all wiring harnesses, substituting a known good IDM and PCM, changing the CPS, and trying various fuel additives for injector lubrication. Fuel pressure and HPOP pressures are great. I have a clear filter housing just before the electric pump and see no air coming from the tank.
Sometimes there just isn't a solution.
I have an injector knock in #7 (passenger side rear cylinder) that remains despite replacing injectors, UVCH, high-pressure oil cross-connect, regulated fuel return, in-tank mods, careful inspection of all wiring harnesses, substituting a known good IDM and PCM, changing the CPS, and trying various fuel additives for injector lubrication. Fuel pressure and HPOP pressures are great. I have a clear filter housing just before the electric pump and see no air coming from the tank.
Sometimes there just isn't a solution.
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ads with the special no. 8
Postmaster
Joined: Apr 2012
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From: North Georgia
Oil can be tested for air (foaming) with a fairly straight forward procedure.
With the engine at operating temp...
Hook up to the trusty obd port with s9mething that can see icp.
Rev up to 3k rpm.
Watch icp.
Hold 3k rmp for 2 full minutes.
If your pressure drops at all while holding throttle... you have air.
Symptom can point to hpop going south.
If the test runs good... start thinking about mechanical issues like foreign object, or piston slap, or play at the rod journals. I strongly recommend you compression test if you have not done so already.
With the engine at operating temp...
Hook up to the trusty obd port with s9mething that can see icp.
Rev up to 3k rpm.
Watch icp.
Hold 3k rmp for 2 full minutes.
If your pressure drops at all while holding throttle... you have air.
Symptom can point to hpop going south.
If the test runs good... start thinking about mechanical issues like foreign object, or piston slap, or play at the rod journals. I strongly recommend you compression test if you have not done so already.
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5 miles
it's quits every once in a while, but now I think the o-rings are out of the oil cooler it's putting water into the oil
it's quits every once in a while, but now I think the o-rings are out of the oil cooler it's putting water into the oil