#7
Timing chain job and all coolant pipes are all done 137k miles.
Hello my 2012 xj 5.0 n/a has a loud start up for about 5 seconds and then sounds fine when gets to low idle and drives great. Sounds like lifters or something up top, almost like a deep rubbery knock. We did the timing job, waterpump, coolant pipes, idler and tensioner pulley so far. No exhaust leaks. The chain was definitely was loose but I have driven it like that for a year now and the noise has never changed. Day of startup after timing job and it sounds exatcly the same! And now the mechanic is getting loud clicking from the a/c compressor (so he thinks)which has never happened belore. Is it a cam or a phaser? Crankshaft? I know the fuel injectors can be loud. What else can be noisy for about 5-10 seconds on start up? Oil starvation or hydraulic tensioner on chain not getting oil soon enough? Knock sensor maybe? Am I getting any oil pressure? Ive heard several that arent noisy like mine. What else makes noise or fails with the aj133 motor please? Thank you for any help!