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- 2019 PP1 GT Kona
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Mustang folks;
It appears as if Ford has an issue with the S550 Coyote intake manifolds cracking. My car is currently at the dealership having it's IM replaced, and evidently the part number is new/revised. I have requested to see the failed IM, so hopefully I can get a pic of what broke at 8400 miles. Evidently there is a runner where a valve is, and it cracks there.
The symptoms are low-RPM misfires that feel like subtle bucking/surging. Mine occurred between 1500RPM and 2100RPM, and it annoyed the every living shit out of me. The engine pulled like a train once past 2100RPMs, but was dog-guano at low revs when just cruising. It's most noticeable in 5th and 6th gears, just cruising along. If I cruised for 20 minutes on the freeway in that RPM range, I'd get a CEL, misfire codes, and have to do a crank position sensor re-learn.
I've perused the "Issues, Repairs, Warranty, TSB, Recalls" sub-forum, and found thread after thread that had similar symptoms to my car, and I think it's fair to think that the symptoms may be different from one car to another. The RPMs the misfires occur at might change, for instance, based on the severity of the crack,
Anyways, if anyone has bucking/surging, misfire CELs, your IM might be the issue.
It appears as if Ford has an issue with the S550 Coyote intake manifolds cracking. My car is currently at the dealership having it's IM replaced, and evidently the part number is new/revised. I have requested to see the failed IM, so hopefully I can get a pic of what broke at 8400 miles. Evidently there is a runner where a valve is, and it cracks there.
The symptoms are low-RPM misfires that feel like subtle bucking/surging. Mine occurred between 1500RPM and 2100RPM, and it annoyed the every living shit out of me. The engine pulled like a train once past 2100RPMs, but was dog-guano at low revs when just cruising. It's most noticeable in 5th and 6th gears, just cruising along. If I cruised for 20 minutes on the freeway in that RPM range, I'd get a CEL, misfire codes, and have to do a crank position sensor re-learn.
I've perused the "Issues, Repairs, Warranty, TSB, Recalls" sub-forum, and found thread after thread that had similar symptoms to my car, and I think it's fair to think that the symptoms may be different from one car to another. The RPMs the misfires occur at might change, for instance, based on the severity of the crack,
Anyways, if anyone has bucking/surging, misfire CELs, your IM might be the issue.
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