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Poor acceleration & loud whoosh noise under full throttle?

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Old May 3, 2024 | 06:29 PM
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OleMissRbl's Avatar
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Default Poor acceleration & loud whoosh noise under full throttle?

I have an ‘03 with new Tom Woods driveshaft, just changed transmission filter/fluid, new O2 sensors, new fuel pump, MAF, CPS, & I have low power & a whooshing noise from what sounds like driver side engine bay under hard acceleration. It almost sounds like the noise a skil saw makes when you pull the trigger. If I let off the throttle a bit it stops, but things like getting on the interstate on a short ramp, or overtaking another vehicle all cause the issue. After changing O2 sensors and fuel pump, still getting codes P0462, P1171 & P1174. Any ideas?
 
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Old May 3, 2024 | 09:43 PM
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PickleRick's Avatar
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Any time I hear swooshing or other air type noises I always think air leak. Smoke test time.
 
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Old May 3, 2024 | 09:51 PM
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P1171/P1174 can be many things. Many try the MAF and/or O2 sensors. Since you have recently changed those parts I would try a smoke test. It could be a vacuum related issue. If not, the poor acceleration along with the 71/74 code could be the O-Rings on the fuel injectors. I chased these codes for a long time (New MAF, vacuum lines & cleaned the Idle Control Valve) In the end it was the injector O-Rings. I pulled the injectors and sent them out to be serviced (mrinjector.us). Sent back rebuilt and a flow report. New o-rings included. Others buy them on Ebay. One of the symptoms I experienced was an idle surge after driving on the highway. Pull into a parking spot and put it in park and the idle would jump above 1K and hang.
 
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Old May 4, 2024 | 12:04 AM
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Could whoosh just be the fan? Is it running hot enough for the fan clutch to lock up?

How is the ignition system? My trucks got new life breathed into them with new plugs, wires, and coils (plus Accel injectors or 4-hole Ford).
 
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Old May 4, 2024 | 12:48 AM
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Originally Posted by JohnZo
Could whoosh just be the fan? Is it running hot enough for the fan clutch to lock up?

How is the ignition system? My trucks got new life breathed into them with new plugs, wires, and coils (plus Accel injectors or 4-hole Ford).
No, I installed a new HD fan clutch when I bought it less than 3k miles ago, & it happens at cold start as well. Once it hits high enough rpms, acceleration stops, & that noise continues until I back off the gas. It feels & sounds like a pressure release valve opening up, then closing once pressure lowers. Entire top end of the engine was rebuilt by previous owner 20-30k miles ago, so all that stuff is new. Only 113k miles on the truck total.

I have smoke tested it previously and only had a leak from brake vacuum line intake seal, which I replaced. I read in another thread that bad injector rings won’t leak smoke because the pressure isn’t high enough, so combined with what others have said here, acceleration issues, p1171/p1174 codes, & ~7mpg, I’m leaning towards injector issues. I’m going to smoke test again before messing with the injectors though.
 
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Old May 4, 2024 | 01:50 PM
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I think I found the issue. PO used epoxy to repair a crack in the air outlet tube coming off the MAF, it got crusty and started flaking off, allowing air to escape under high engine load. I removed more of it to test if it made it worse while accelerating, and it did. I just covered it in RTV silicone and covered that in epoxy, & will retest once dry, & will replace with an undamaged one I can find online. If anyone has one they want to offload, I’m a buyer.

 
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Old May 4, 2024 | 04:08 PM
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Good to hear that you figured it out
 
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Old May 8, 2024 | 08:10 PM
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Well, that wasn’t it. You can hear the whoosh sound in the video when it hits ~45mph. It’s much louder with the window open, but the wind was too loud on video. Any ideas? Again, it only happens at ~3200 rpm at any speed.
 
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