Questions and Answers

Chevy Corsica Cold Start Tapping Noise Q. Hi Vince, I'm Simon form Israel (remember me? "Corsica Has The Shakes") I have 1995 Chevrolet Corsica 3100 V-6, 4T60E automatic transmission, 282,000 kilometers (in very good condition, everything is done on time) My problem is: when I start my car, most of time on cold start but even on hot start, after 10 or 20 seconds I hear a " tak" noise from the engine Like tak... tak... tak... for one minute then the noise disappear.

It can disappear immediately if I shift to a gear, Drive or Reverse. Some time the engine doesn't make any noise at all. I found out that if I accelerate in Park or Neutral gear and then I leave the accelerator the all engine moves and make a strong "tak". By the way the car runs 100% okay!!!!!!!!!!!!! What can be the problem engine or transmission? I rebuilt my transmission at 200,000 kilometers.

Thank you,
Simon

A. That engine is prone to a piston slap. Obviously I can't hear it to be positive, but I'm sure if you've taken care of it, it should be okay as it is. If it's loud enough to be heard from inside the car, then I would try to isolate the noise. If you think it could be the transmission you can remove the torque converter bolts so it won't spin while the engine is running to see if the noise is gone. Good luck!

Bulletin No.: 57-61-24A
Date: June, 1998

Subject:
Cold Engine Tick or Rattle After Start-up (Replace Piston/Pin Assembly)

Models:

• 1994-95 Buick Regal
• 1994-97 Buick Skylark
• 1994-98 Buick Century
• 1994-95 Chevrolet Beretta, Corsica, Lumina, Monte Carlo
• 1996-98 Chevrolet Venture
• 1997-98 Chevrolet Malibu
• 1993-97 Oldsmobile Cutlass Supreme
• 1994-96 Oldsmobile Cutlass Ciera
• 1994-97 Oldsmobile Achieva
• 1996-98 Oldsmobile Silhouette
• 1997-98 Oldsmobile Cutlass
• 1994-98 Pontiac Grand Am, Grand Prix
• 1996-98 Pontiac Trans Sport with 3100, 3400 V6 Engine (VINs M, E - RPOs L82, LA1)

This bulletin is being revised to expand the model year coverage, add the 3400 V6 Engine applications and arts information. Also, the Cause statement has been changed. Please discard Corporate Service Bulletin 57-61-24 (Section 6 - Engine).

Condition:
Some customers may comment on a ticking type noise that begins shortly after cold engine start-up and gradually diminishes as the engine warms up. In most cases, the noise is gone after five (5) minutes. In severe cases, the noise may not disappear when the engine is hot.

Cause:
Under normal design tolerances when the piston pin bore is produced at the maximum tolerance and the piston pin is produced at the minimum tolerance (min-max tolerance) trace noise levels can occur. This level of noise does not affect the reliability or durability of the product.

Correction:
If piston-to-pin noise is detected and the customer desires the condition to be corrected, replace all six pistons with pin assemblies. The new piston sets have a minimal piston-to-pin clearance. Remember, piston-to-pin noise occurs in both park and drive at engine idle rpm and it varies in intensity depending on the number of pistons involved. A ticking sound means one piston is affected whereas a rattle or diesel type sound indicates more than one piston affected.