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Head Torque

Q. My buddy bought a 1990 Cadillac Sedan DeVille with 90,000 miles on it 3 months ago and took on a 5000 mile trip, it ran fine but it did use about 6 quarts of oil. It's got a 4.5 port fuel injected 272 cubic in engine, ABS brakes, P/S, A/C and Cruise.

The problem is; It doesn't miss when he starts it in the morning but when it is warmed up it misses on number 5 cylinder. The head was taken off and put back prior to him buying it. He is going to remove the head to find out what the problem is and what he needs know is the torque and sequence for the head and intake manifold. Would appreciate any advice that you could give him.

Thank you and have nice day,
Granville

A. The torque sequence is:

6     3     1     4     5

10   7     2     8     9

The torque depends on the bolt length. Measure the threaded portion of the bolt. If it measures 39 mm you have short bolts. If they measure 41 mm, you have long bolts.

Torque for short bolts:

  1. Step 1: 30 foot pounds
  2. Step 2: 52 foot pounds
  3. Step 3: 85 foot pounds
  4. Step 4: 90 foot pounds

Torque for long bolts:

  1. Step 1: 30 foot pounds
  2. Step 2: 52 foot pounds
  3. Step 3: 85 foot pounds
  4. Step 4: 90 foot pounds
  5. Step 5: 96 foot pounds for the three center inboard studs. #1, 3 and 4.

Make sure the threads are clean. use a fluid such as CRC 5-56 to lubricate the threads. Do not use motor oil to lubricate the threads as this will not give you an accurate torque reading.

Additional Information provided courtesy of ALLDATA

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