Service Slants

Motor, May 2004 by Savasta, Bob

Isuzu

MIL illuminated, DTC 1870 stored in PCM memory. Some 19?6-99 Troopers and Rodeos, 1998-99 Amigos and 1999 VehiCross models may turn on the MIL and store DTC 1870 in computer memory. According to Isuzu powertrain engineers, the problem is often accompanied by a blinking or steady Check Trans light, and is most likely due to insufficiently tightened converter housing-to-main case bolts. The loose bolts cause the separator plate gaskets to slip out of position. That causes an internal pressure leak, which in turn causes the fluid pressure to the lockup clutch to drop like a rock. It's this pressure loss that causes the MIL to illuminate and the DTC to set.

The fix involves tearing down the box and installing new gaskets (Part No. 8-96016-514-0) on both sides of the separator plate. Tightening the converter housing-to-main case bolts in a cross pattern to an upwardly revised torque spec of 40 ft.-lbs. prevents the gaskets from taking another walk. If you do tranny work and would like to tackle the job, here's a complete list of the parts you'll need:

GM Truck

Theft-deterrent system change. GM wants you to be aware that it has eliminated the shock sensor from the theft-deterrent systems of 1999 and later Cadillac Escalades and GMC Yukon Denalis. The phase-out was completed by midyear 1999 production, with replacement sensors dropping out of the GM parts pipeline a short time later.

If you come across a defective shock sensor, under no circumstances should you attempt to replace it, warns GM, even if you can somehow scam one from your local Cadillac or GMC dealer. Simply remove the sensor, then tape over the harness. Make sure you secure the harness with a nylon tie to prevent rattles and other noises. GM says that eliminating the shock sensor will in no way alter the other operating characteristics of the theft alarm.

Dodge

Instrument panel rattle. Dodge says that some of its 2003-04 Vipers (build date prior to 11/1/03) can give off an annoying rattling noise from the instrument panel when going over rough road surfaces. Abnormal contact between the center defroster duct flange and the defroster grille and/or instrument panel substrate is the most likely cause of the noise.

To check things out, tap on the IP near the center duct and listen for the rattle. If you hear it, pry upward on the defroster grille using a trim stick and remove the grille from the instrument panel. Next, remove the center defroster duct mounting screws and the duct itself. Using a pair of tin snips or a similar tool, start cutting away the outer flange of the duct around its entire circumference. Remove all debris from the duct area of the IP, then reinstall the center duct using the two mounting screws. To complete the fix, install the defroster grille (making sure it's fully seated), then repeat the tap test to confirm that the rattle has been eliminated.

Chrysler

Multiple driveability problems. Some 2004 Sebring and Stratus models with the 2.7L engine can exhibit a bumpy 2-1 downshift, an erratic idle or general engine roughness when slowing to a stop. Chrysler engineers say the symptoms are much more prevalent in stop & go driving with the a/c turned on, and are limited to vehicles produced between 7/2/03 and 11/24/03.