Knocking sound at take-off
#1
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Year: 2000
Model: Cherokee
Engine: 4.0 Inline 6
Knocking sound at take-off
So I just had my engine swapped, everything is going well, and I believe that he did everything correctly, but ever since he did the swap, I have this rattle/knocking from somewhere underneath behind driver seat, only when I take off decently hard from a full stop.
I naturally thought it was probably the exhaust hitting the crossmember, but I went underneath and could not get the exhaust pipe to even hit the crossmember. I replaced the rubber part of the rear exhaust hanger just for good measure, still no change.
I tried wiggling everything possible underneath the rear end, and I cannot recreate the sound.
What else could cause this noise only for the first second or two after hitting the gas from a full stop.
Any other ideas of what to check for would be appreciated.
I naturally thought it was probably the exhaust hitting the crossmember, but I went underneath and could not get the exhaust pipe to even hit the crossmember. I replaced the rubber part of the rear exhaust hanger just for good measure, still no change.
I tried wiggling everything possible underneath the rear end, and I cannot recreate the sound.
What else could cause this noise only for the first second or two after hitting the gas from a full stop.
Any other ideas of what to check for would be appreciated.
#3
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Year: 2000
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Thanks for the answer man and I hate to burst your bubble, but unfortunately I had him put in new u-joints, and it had no effect on the noise. I am speaking about the two rear driveshaft ujoints
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lol swing and a miss realmortician! i know how you feel though, i get pumped when i can finally be useful on here to haha. but sadly... this is not one of those times
If it is under hard acceleration, maybe you’re getting a little body / driveline twist that’s allowing your exhaust to reach a contact point??? You mention its momentary, if it was something like u-joints or something rotating, you think it would be constant….
If it is under hard acceleration, maybe you’re getting a little body / driveline twist that’s allowing your exhaust to reach a contact point??? You mention its momentary, if it was something like u-joints or something rotating, you think it would be constant….
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Year: 2001
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Get it on a lift with some in the jeep and someone under. Place gear selector in driver or 1st gear. Hold brake hard and mash on the gas a few times. The person below needs to look for any obvious movement. You will find your problem then.
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