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2000 Cadillac Seville Repair Question


Topics covered: Engine, Rpm, Noise.
Mileage: 135,000 miles.

Asked on January 22, 2012

I'm getting a grinding noise when i hold the revs @1000 rpms (approx. 20=25 mph)

If i drive thru the gears, approx. to 50-60 mph, no problem. but if i have to drive thru town at 20-25 mph, i have to keep my rpm's to approx 1000, thats when i hear (and feel)the grinding noise. i just had the tranny replaced last Sept, after that i been getting a P0327 code. i dont know if that has anything to do with anything. i had the knock sensor replaced. im just ready to drive this beast off a bridge...LOL!
Avatar Asked by thunder

Answer

Replied on January 22, 2012

The knock sensor's job is to retard the ignition timing when the engine starts pinging the noise it makes is like dropping marbles in a tin can-start checking all the pulleys-could be a driven component bearing

Tiny Answered by rasmataz
68 questions asked
Replied on January 22, 2012

i just had the wtr pump replaced.

Tiny Response from thunder
13 questions asked
Replied on January 25, 2012

Did that fix it thunder?

Tiny Answered by rivermikerat (expert)
5,495 answers provided

Replied on January 25, 2012

No rivermikerat, but it did stop the coolant leak. I also noticed the other day a rattling noise while the car was in park. I cant tell if it's the engine or tranny. Any ideas?

Tiny Response from thunder
13 questions asked
Replied on January 25, 2012

If it was a Ford I'd say the heat shield on the catalytic converter. You might check that. It's in a location that might make you think engine or tranny.

Do you hear the grinding when in park or neutral @1000RPM? Or just in gear? What about if you toss it (carefully) into neutral while driving and bring the RPM to 1000? You could have a hub or wheel bearing going out but not be able to hear it at higher speeds due to normal road noise.

Tiny Answered by rivermikerat (expert)
5,495 answers provided
Replied on January 25, 2012

i can hear the rattling in park, (Marbles in a canister), i feel the shruddling always when driving, when i drive home from work, there's a hill (in a resident area) that i have bear, so i have to go approx. 25-30 mph. I noticed there's no smooth gear transition and i also noticed that my engine will holds @ 1000 rpm if i hold the pedal in position for the next gear change. i sure you understand, that's there's a pedal position that you can hold for your car to smoothly go thru its gears. i sometimes have to quick pedal it to "unstuck" it off a 1000 rpms for it to run smoothly into gear. 1200 rpms is ok, but @ 1000 (23-25 mph) the whole car shakes. This doesn't happens to obtain highway speeds or transition, she shifts smoothly. just when i have travel round town. I'll check the heat shield. Something tells me i'm going to have take it back to the tranny people AGAIN!

Tiny Response from thunder
13 questions asked

Replied on January 25, 2012

The transmission shifts based upon engine speed and vehicle speed. So, holding the engine speed steady shouldn't make the transmission shift smoothly. It should just keep the vehicle speed steady, on level ground.
It sounds like you have multiple problems. The grinding sounds like a bearing.

And it sounds like your engine is experiencing pre-ignition. Does the 'marbles in a can' sound speed up when the engine speeds up?

Tiny Answered by rivermikerat (expert)
5,495 answers provided
Replied on January 26, 2012

i don't hear anything while i'm driving (of course), now that i think of it, i only hear it when idling in park. Today it something different, it started bucking instead of the usual shuddering, i had to pedal it to make it stop. I understand what you mean about engine and vehicle speed. Lets just say, when it shifts and the rpms falls to the low 1000's revs, that's when i experience the shuddering. All of this is happening, and no check engine soon light yet. Should i check for codes?

Tiny Response from thunder
13 questions asked
Replied on January 26, 2012

Yes. You want transmission codes, especially. But tell the shop or parts store you need soft codes. Those won't set the CEL.

Tiny Answered by rivermikerat (expert)
5,495 answers provided
Replied on January 26, 2012

Soft codes? that's the first time i ever heard that term anywhere. i usually just check the OBD from the Dashbore. is that the same?

Tiny Response from thunder
13 questions asked