97 SC400 Engine/Transmission Noise from 30-60 mph

Hi All:

I just got a used '97 SC400, enjoying the driving experience and I
slowly fixing up little problems here and there.

I am not sure about previous owner's maintainance habit, so far the car
runs fine except when accelerating on the HWY from 30-60 mph, the
engine and/or transmission tends to 'work very hard'.

I wonder it is because it is time to do a major tune up or the engine
and/or transmission mounts needs to be replaced ?

Please share your opinion/experience.


BR,

V.

"Vinny" <e2vincent (AT) yahoo (DOT) com> wrote

Hi All:

I just got a used '97 SC400, enjoying the driving experience and I
slowly fixing up little problems here and there.

I am not sure about previous owner's maintainance habit, so far the car
runs fine except when accelerating on the HWY from 30-60 mph, the
engine and/or transmission tends to 'work very hard'.

I wonder it is because it is time to do a major tune up or the engine
and/or transmission mounts needs to be replaced ?

Please share your opinion/experience.


BR,

V.

You didn't mention vehicle mileage, but if mileage is a multiple of 60,000
miles, I would have the spark plugs and timing belt checked because they
need replacement at those intervals. Also, check the condition of the
transmission fluid. Bad motor or transmission mounts will not make the
engine work harder, and the symptoms of bad ones is usually a vibration or
noise.
--

Ray O
(correct punctuation to reply)

Good tips.

I bought it at 125K miles, now it is 130K miles.

AFAIK, timing belt should be changed around 90K, hopefully the previous
guy had done that.

I guess he is lacking the 120K miles major service, since he is selling
his car. I guess I will do that (include what you had suggested).

V.
Ray O wrote:

You didn't mention vehicle mileage, but if mileage is a multiple of 60,000
miles, I would have the spark plugs and timing belt checked because they
need replacement at those intervals. Also, check the condition of the
transmission fluid. Bad motor or transmission mounts will not make the
engine work harder, and the symptoms of bad ones is usually a vibration or
noise.
--

Ray O
(correct punctuation to reply)

Hi Ray:

I did a major tune up where I changed the A/C filter, oil filter, fuel
filter, replaced gaskets, changed engine oil, transmission oil, flushed
coolant, checked timing belt and drive belt, replaced spark plugs, and
the whole 9 yards.

The car runs smoother now, still... can hear the engine noise when
accelerate while it is in 20-60 MPH range. Strangely, it is less noise
from the passenger's side.

Anything else anyone can think of ? If the noise is by design, I've got
nothing to complaint about but to live with it then.


BR,

V.
---------------------------------------------------------------------------------------------------
Vinny wrote:

Good tips.

I bought it at 125K miles, now it is 130K miles.

AFAIK, timing belt should be changed around 90K, hopefully the previous
guy had done that.

I guess he is lacking the 120K miles major service, since he is selling
his car. I guess I will do that (include what you had suggested).

V.
Ray O wrote:
You didn't mention vehicle mileage, but if mileage is a multiple of 60,000
miles, I would have the spark plugs and timing belt checked because they
need replacement at those intervals. Also, check the condition of the
transmission fluid. Bad motor or transmission mounts will not make the
engine work harder, and the symptoms of bad ones is usually a vibration or
noise.
--

Ray O
(correct punctuation to reply)

"Vinny" <e2vincent (AT) yahoo (DOT) com> wrote

Hi Ray:

I did a major tune up where I changed the A/C filter, oil filter, fuel
filter, replaced gaskets, changed engine oil, transmission oil, flushed
coolant, checked timing belt and drive belt, replaced spark plugs, and
the whole 9 yards.

The car runs smoother now, still... can hear the engine noise when
accelerate while it is in 20-60 MPH range. Strangely, it is less noise
from the passenger's side.

Anything else anyone can think of ? If the noise is by design, I've got
nothing to complaint about but to live with it then.


BR,

V.

Without actually hearing the sound, it is difficult to say whether it is
normal or not and what the source of the sound is. You may want to check
the heat shields for the exhaust manifold catalytic converter(s) and exhaust
system to see if any of them are loose.
--

Ray O
(correct punctuation to reply)