: Small engine knock and low idle in park

12-13-08, 04:14 PM
I have a 2000 Catera with a brand new engine that I installed about 8 months ago. I got a brand new crate motor from LA it was suppose to go into the 2002 Catera. The car has been running great with no problems and since the new motor is a 3.2L I have quite a bit more torque. My problem is when the car is stopped or in park! The idle is low and there is a very small knocking noise which I persume is from the low idle. I would really like to know how to adjust the idle I'm currenlty running around 600 RPM in park but when I put the car in neutral the knock goes away and the idle comes up to about 800 RPM. Any help would be greatly appreciated. Also does anyone know what the idle should be!!

12-14-08, 10:56 AM
Idle should be about 500 or 600 rpm in the cold. I'm not sure how to adjust the idle, but where exactly did you find that engine? And how much torque does it put out?

01-04-09, 01:12 PM
I had the same problem with mine. Here's what I found out and fixed it, In my shop manual it states when you have a low knocking sound in park and goes away it is from your torque converter is not balenced with your flywheel, you will have to turn you torque converter 1/6 of a turn. Do this each time untill it goes away. It's time cosuming but it will fix it. I had to turn mine 5 times. Hope this helps.

01-05-09, 12:07 AM
I have a similar problem in my car with the knocking noise and I cant seem to find where its coming from. Does this torque converter knock sound like drumming on the bottom of a large empty cooking pot with a wooden spoon???
I hear a noise just like that and I cant figure out where the heck its coming from. It happens whether I am idling in park or stopped at a light in drive and comes and goes as it pleases.

01-08-09, 08:20 PM
Your problem sound different then a converter. What dose your oil pressure read when the knock accrues?

01-08-09, 10:03 PM
My knocking occurs at any random moment whether the car has just started or after a lengthy trip. I only hear it at idle, although when the engine revs up it kind of drowns out other noise. The noise almost seems to follow the RPM, but if you pay close attention IT DOES NOT. The idle and oil pressure remain steady during the thumping.
As the thumping goes on it slowly gets faster and faster until you cant distinguish it and it becomes a constant noise of its own. By then you cant tell its happening anymore. It starts at about 4-5 thumps per second and noticeably rises after around 30 seconds to about 10 thumps per second and a few seconds later it thumps so frequently that the noise sort of blends into the idle noise of the engine and is unnoticeable. Just as soon as this happens, about a minute later it will reoccur very noticeably out of nowhere with the 4-5 thumps per second.
The idle speed and oil pressure do not fluctuate whatsoever with the stock gauges when this occurs. With a very accurate precision gauge set fluctuations may be noticeable but I do not have aftermarket gauges in the car, nor do I have any to test the car with.
I have also determined it is not side effect noise of the secondary air injection pump or the rear leveling air pump. I also ruled out serp belt slap because the belt is in fine condition with no flaps whipping around and also it would directly correlate to the engine RPM.

Po Pimp
01-09-09, 08:54 PM
The warm idle should be 450 RPM by federal mandate. This is a custom so I am not sure what to tell you there. Did you reuse the IAC valve from your 3.0L engine?

Is your AC or heater on when you hear the ticking?

Those Harrison V-5 compressors make a ticking sound directly proportional to RPMs on some cars.

01-11-09, 01:04 AM
Harmonic balance? Maybe, see if its lose...