Niagara Gazette — BERT FROM SAN DIMAS, MEXICO: I own a ‘04 Toyota Highlander 4 cylinder, 82,000 miles. My local shop sent me a notice to have the EFI throttle body serviced. What is an EFI throttle body and how often does it need service? The vehicle is running fine, so I wonder if this service is really necessary at this time?
TOM: EFI stands for Electronic Fuel Injection and Throttle Body is the term for a component in the injection system where air is taken into the engine. Fuel injection systems require cleaning at regular intervals, every 35 - 40 thousand miles. This process is necessary because varnish deposits, dirt, and carbon build up on the end of the injector nozzles, inside fuel rails, inside intake plenums, on the tops of the pistons, and inside the cylinder heads and valves. The cleaning process involves injecting an industrial grade carbon cleaner into the system, and then letting it sit to liquefy any carbon buildup in the engine. A professional cleaning of the injection system and upper regions of the engine usually results in increased performance and better fuel mileage.
RUTHANN FROM EAST AURORA: I own a ‘91 Chevy S10 pickup, 4-cylinder. The oil gauge goes spastic at times. Also, the pressure runs low on the gauge when it isn’t acting up. Finally, nearly every time the vehicle turns left I hear this loud popping, clunking sound. Any idea what that could be?
TOM: In regards to the spastic oil pressure reading, run an oil pressure test with a mechanical gauge to confirm actual oil pressure. If it is low, the engine will have to be disassembled for proper inspection of the parts that relate to oil pressure. If the oil pressure is okay, then check for a bad sending unit or wiring to the unit (this is most likely the cause of the erratic readings). The popping sound could be a bad ball joint, control arm bushing shock, or some other suspension part. Get the truck up in the air for a suspension inspection. Success to you.
BOB FROM KANSAS CITY: Help! I own a ‘90 Corvette with 112,000miles. Recently, the car developed a “knock” which the mechanic says is a rod (I’m not sure exactly what that means). He painted a dismal picture of rebuilding the engine (estimated at $3,000) or completely replacing it (estimated at $5,000). Please explain the “rod” problem and how it could have occurred in a seemingly sound engine. Also, does the mechanic’s analysis sound like it makes sense?
TOM: I can’t answer why the knock appeared so suddenly unless I explored the engine. The cause could be a bad oil pump, excessive sludge buildup preventing oil flow to bearings, bad engine oil, as well as a host of other reasons. Pistons are connected to the crankshaft via a connecting rod. The rod bolts to the crank using a split metal cap. Bearing inserts are placed on the cap and this surface is what rides in the crankshaft journal. Oil is pumped into the bearing saddle and acts as a cushion between the crank journal and the bearing surface. The reason for the knock? The bearing inserts at the end of the connecting rod have worn out, causing a hammering (or knocking) effect when the piston travels up and down. Your mechanic’s assessment of replacement or rebuilding is probably accurate. Before sentencing your engine to death in the bone yard, drop the oil pan and inspect the crankshaft to evaluate the extent of the damage. I wish you success.
BARB FROM ALGONQUIN: I own a ‘99 Dodge Ram Conversion van with 60,000 miles. For the past several months, the red ABS light stays on when I start the vehicle. However, it turns off when I drive the vehicle. The only place I know to take it to is the tire store in my town. I am afraid they are going to say I need rotors. I want them to pull off the wheels and show me the pads and rotors, but I don’t think they will like this idea. My husband said I should NOT ask to see these parts, but I want proof that I need them. I am expecting to have to pay a fortune! On a side note, is it true that, if an older car has never had the transmission fluid changed, changing it could “wreck” the transmission?
TOM: If you think the shop will not like the fact that you want to see the parts that need replacing then you are going to the wrong shop (and your husband has the wrong attitude). As a consumer you are entitled to see why the work needs to be done. I suggest you find a dependable repair shop if this tire shop will be offended because you want to see what needs repairing or replacing. Call your local Triple A, ask for an Approved Repair Center in your area, and get a second opinion. As for the ‘lit’ ABS light, the brake computer has to be scanned for codes and the malady repaired (perhaps a speed sensor, broken wiring, or hub assembly). In regards to the transmission question, if the fluid in your trans were burnt or very brown, then yes, I would say to leave it alone because the trans has probably been overheated. When a trans overheats it cooks the clutches and rubber seals. When you replace the fluid on a ‘cooked’ unit, the clutches come unglued from their backing and the unit fails. Good luck.
‘Til next time…Keep Rollin’"America's Car Show" with Tom Torbjornsen airs 7:30 p.m. Wednesday, 9 a.m. Thursday and 11 a.m. Saturday on WBBZ-TV.