Quote:
Originally Posted by strother
I've probably asked enough basic questions to brand me for life, but I've got another one. Before I start, I'll tell you that I've spent the past 1.5 hours reading archived posts that turn up when I search "load" and "noise"...
My engine makes a rattling noise briefly when I accelerate hard under load -- usually from about 2000-3000 rpms or so in 2nd gear when driving around the neighborhood. It isn't horribly loud, but it is an additional sound on top of the engine noise. The noise only lasts a second or so until the rpms pick up in the gear I've selected. This is going to make it sound worse than it really sounds, but it reminds me of the sound a bus makes on accelration.
Is the sound normal? After reading the archived posts, I'm paranoid about broken head studs, and worried about timing and mixture. You should know that I just had the engine tuned up, including valve adjusment. It was doing this before and after the tune up.
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Hi All,
I'm pulling an old post forward to get some clarifying thoughts....the original post outlines the issue sounds very similar to one I'm having, but want to clarify the scenario a bit.
Part 1:
I'm getting this same gravel-like 'dieseling' sound from the power train. It has a mid-timbre sound, has a substantial presence over the normal cruising engine sound, but is not loud. I can't hear the sound when the convertible top is up, but it is very prevalent when the top is down.
The sound happens between 2500 - 3500 RPM's and is there under load, but is present under light throttle as well as heavy throttle. The timbre is a little more 'tinny' under light throttle than under heavy throttle. and goes away when you take your foot off the throttle. The time I hear the sound most is when I'm under light throttle at around 3k RPMs cruising. The sound is not there when sitting still in neutral, either at idle or revving the motor.
Part 2:
Now, not sure if this is related or not, but I hear a separate and different noise when I'm idling that is coming from the area around the heat shield under the cat -
Here's the weird part on part 2: when that sound eminates, i've noticed that the Oil pressure guage needle lifts bearly (1/8") and freezes (instead of bouncing about as usual) while the sound is eminating. This sound is intermittent, lasts about 3 seconds each time, and re-occurs about every 20 - 30 seconds on average when idleing.
These sounds sound quite different from one another and they are in different situtations, but these sounds have also been both suggested as being connectected to one another in this thread. (cat baffles deteriorating, or heat sheild coming loose.) I'm just not so sure, as the Part 1 sound gives a more substantial presence (more than just a loose piece of tin like in Part 2)....
The sound is quite disconcerting, and I want to make sure it is nothing critical like the chain tensioner. I know it is hard to diagnose a sound through words, but I'm looking to see if anyone can shed any light/experience that would help distill this further to help determine if this is a chain tensioner, cat going bad, head sheild coming loose, or normal tranny noise.
Thanks!!!