Service Slants

Motor, May 2008 by Rosario, Tom

Toyota

Drive belt squeal. Owners of 2000-06 Tundra pickup trucks may complain of an annoying squealing sound coming from the front of the engine. According to Toyota, the noise is most obvious during cold-engine start-up and is due to the serpentine drive belt slipping on the accessory pulleys. Installing a new-design automatic belt tensioner (Part No. 16620-0W100) along with a revised a/c compressor mounting bracket (Part No. 88431-0C012) should help eliminate the annoyance.

Start the fix by removing the lower engine cover, then drain the cooling system. Now remove the intake air duct and the radiator fan shroud, followed by the drive belt, fan, fluid coupling and fan pulley. Next, remove the power steering pump and position it aside, leaving the lines connected.

Continue the job by removing the idler pulley and the right-side and left-side timing belt covers. Leaving the refrigerant lines connected, remove the a/c compressor from the old mounting bracket. Now remove the mounting bracket and toss it.

Using the illustration above right as a guide, install the revised compressor mounting bracket along with its three retaining bolts. While pushing the bracket forward, hand-tighten bolts 1 and 2 only! As you continue to hold the mounting bracket toward the front of the truck, tighten all three retaining bolts to 35 ft.-lbs in the following sequence: 2-1-3. Don't skip this step because it helps to preload the bracket.

Reinstall the compressor to the mounting bracket. Now remove the old automatic belt tensioner and install the new-design unit in its place. Torque the two retaining nuts and one bolt to 12 ft.-lbs. To complete the repair, put everything back together, refill the cooling system, start the engine and confirm that the belt squeal has been eliminated.

GM

Intermittent a/c operation, driveability issues. Drivers of 2000-02 Chevy Cavaliers and Pontiac Sunfires with the 2.2L (VIN 4) engine may complain that their air conditioning system operates erratically or not at all. The a/c symptoms may be accompanied by driveability issues, including a hesitation, surge or misfire on acceleration. In addition, the MIL may be on, with DTC P0530 stored in computer memory.

According to GM, all these complaints could be the result of an intermittent connection at the a/c pressure sensor harness. One likely cause for the bad connection is that the harness was manufactured too short, which causes it to break connection with the pressure sensor when the engine twists on its mounts during acceleration.

The only reliable fix is to solder an extension harness and connector (Part No. 12102748) into the existing pressure sensor harness. That adds about 6 in. to the length of the harness and should put an end to the a/c problems and driveability issues. After the extension is wired up, wrap the entire harness in electrical tape, then make sure it's routed away from all moving parts and sharp edges. Complete the job by securing the harness to the a/c compressor inlet hose with a nylon tie strap.

Ford Truck

Low power, oil leak at intercooler connection. Some 2004-05 F-Super Duty pickups and Excursion SUVs with the 6.0L diesel engine and build dates between 4/1/04 and 2/20/05 may produce a complaint of low power, possibly accompanied by oil leakage at an intercooler duct connection. The fix depends on what you find when you inspect the intercooler ductwork and where the oil leak is emanating from.

If the duct from the cold-air side of the intercooler has blown off at the intake manifold or leaks oil at the intake manifold elbow, install a special reinforcing ring (Part No. 5C3Z-6F082-AA) to the end of the duct, making sure the bead in the duct sits squarely in the groove in the intake elbow. Torque the clamp bolt to 106 in.-lbs. to finish off the repair.

If the cold-air side duct has blown off at the intercooler end, leaks oil at the connection or has a hole or other defect, install a new metal duct from a kit (Part No. 6C3Z-6C640-AA) between the engine and intercooler. After the new duct is installed, again make sure that the bead in the duct sits properly in the groove in the intake manifold elbow. Tighten both clamp bolts to 106 in.-lbs. and the fix is complete.

Nissan

Low power, transmission stuck in 3rd gear. Some 2004-05 Quest minivans (build date before 9/17/04) may suffer from low power, which is often accompanied by the transmission being stuck in fail-safe mode (locked in 3rd gear).

According to Nissan, the problem usually occurs right after the engine is started, and typically disappears after the key is turned off and the engine is restarted. In addition, vehicle speed sensor DTCs are often logged in the transmission control module (TCM), although the MIL rarely illuminates when the codes are stored. A bum TCM is the likely cause for all the complaints. Installing an upgraded control module (Part No. 31036-ZF09A) should eliminate further trouble.

Saturn

Doors hard to close. Saturn says that the doors on 2005-07 9-7X models may be difficult to close, and that a misadjusted door striker is the likely culprit. Readjusting the striker should eliminate further troubles. Here's the repair drill: