Service slants

Motor, Feb 1998 by Juran, Ken

GM

Revised coolant fill procedure. If you ever have trouble getting that last belch of air out of the cooling system in a 1996 Chevy Cavalier or Pontiac Sunfire with the 2.2-liter 4-cylinder (VIN 4), maybe you're not doing the refill properly. GM recently revised the procedure for the two versions of this engine. For those 2.2s with hvo bleeder valves-one on the thermostat housing, one on the heater return tube (see illustration)-here's how to go about it:

Make sure the radiator drain is closed and that all engine freeze plugs are in place, preferably with some pipe sealant. Open both bleeder valves. Then fill the system through the surge tank until coolant pours out of both valves, at which time you should close them. Keep in mind that only GM Goodwrench DEX-COOL (orange, silicate-free) or an equivalent coolant that meets GM spec 6277M is allowed. If coolant with silicate is installed, it'll eventually corrode the engine internals, the heater core and the radiator.

Next, top off the surge tank to the ledge just below the vent lines (about 1 inch below the fill neck), but leave the cap off. Start the engine, and open the stat bleeder valve until coolant pours out, then close it. Repeat this every three minutes until the thermostat opens (a hot upper radiator hose). Also have the heater on full hot and make sure you get warm air within the first five minutes. If not, shut down the engine, open the bleeder valves again, top off the system and start over. When no more coolant can fit in the system, pop the surge tank cap on and you're done.

For those 2.2s with just one bleeder valve on the heater return tube and a second automatic vent tube from the stat housing, here's what to do: Open the bleeder valve and fill the system through the surge tank until coolant pours out of the valve. Close the valve and top off the tank to the same level as previously described. Leave the cap off, start the engine and wait until the thermostat opens. Check for warm air within five minutes and repeat from the beginning if you don't get it. Once the system is full, install the surge tank cap.

Dodge/Plymouth

Misrouted engine harness. A 1996 Neon built in Toluca (first VIN digit is 3) prior to 11/22/95 may develop a number of electrical gremlins. They include intermittent operation of the cranking circuit, a/c clutch, idle ajar control, fuel gauge and MIL illumination. All of these symptoms can be attributed to a misrouted main wiring harness. The two 10-wire takeouts near the Power Distribution Center must run over the heater hoses and into the clip on the inboard side of the PDC. The 40-wire PCM takeout must route over the heater hoses with its locator snapped into the speed control bracket or transmission mount. If you don't find things this way, make it so.

Ford Truck

Hesitation, rough idle, poor performance. You may come across a 1995 Econoline or 1994-95 F-250, F-350 or F Super Duty with the 7.3-liter directinjection (DI) turbo-diesel that hesitates, stumbles, idles roughly, lacks power, has lousy performance and fuel economy, stalls and/or burns oil. The cause of these symptoms can probably be traced to poor injector O-ring sealing. The O-rings deteriorate after a while, Ford says. But you can't diagnose the problem routinely, because there probably won't be any codes detected by a Ford Super Star or New Generation Star scanner, or anv other scanner for that matter. So here's what to do:

Pull the injectors and eyeball the 0rings. If they look like they've seen better days, install new beefed-up green O-rings from Ford (Part No. F5TZ9229-B for a kit that includes instructions). Note that if just one O-ring looks bad, they all must be replaced. You can't be selective. Same goes for servicing the injectors.

Jaguar

Engine vibration. Some late-model XJ6 and supercharged XJR models with the 4.0-liter straight Six built before VIN 683923 may suffer from engine vibration or a rough idle while in Drive.

Jaguar says the front engine mounts are to blame, and that new softer ones (Part No. MHC 7521AA, left/MMB 7520BA, right) should be installed.

Porsche

Smoke on startup. The German sports car maker says using the wrong small oil filter will cause engine smoke on startup in a 1995 911 Carrera or a 1996 911 Turbo. Here are the correct part numbers for each car:

Volkswagen

Wrong DTC. VW says a late-model 2.8-liter V6-equipped car could store the wrong trouble code of 00735 in the engine control module when a problem occurs in the evaporative purge system. When dealing with this system,

refer to information on DTC 01247/4343, instead.

BMW

Transmission fluid leak. Bad electrical connector O-rings on the transmission may cause ATF leaks on some latemodel automatic BMW 530i sedan and Touring (wagon) models, automatic-only 540i models and some 740iL stretch models. Before replacing the O-rings (Part No. 24 341421736) on the 530s, remove the parking lock mechanism guide plate. On all of these models, coat the O-rings with ATF before placing them on the electrical connector. Make sure the flattened portion of the connector faces toward the outside of the transmission.