The problem is that at many service establishments the person doing the diagnostics has no understanding of how things work. I NEVER let anybody do diagnostics on a vehicle for that reason. On my NEW Dodge van I had a radiator fluid loss problem, which I discovered was a slightly bent lip on the radiator filler where the cap is supposed to make the top seal. Evidently it caught on something during the installation and was bent up just enough to leak. A real 1 minute repair, but a couple minutes to find. Then at about 5000 miles the starter stopped working consistently. Thedealer told me that it was not covered by the engine warranty since it was an accessory. I purchased a new front armature sleeve bearing, and replaced the worn out one with it, which took a fairly short time since everything was still like new in the engine area. That lasted for the next 20 years. Then I had a noise that sounded like spark knock, except that stepping on the gas made it less loud. That turned out to be the thermal clutch fan, which the dealer also refused to fix under warranty. So I bought a flex fan at a junk yard for $15, and it was good for the next 20 years. After 15 years the automatic choke failed when part of it rusted away, so that had to be replaced. I did that.
The charging system on another car would not charge adequately, and I traced that to a slightly loose connection of a ring terminal lug. A similar complaint on a friends Chevt love pickup I traced to a connector pin on a multi-pin connector that had not been seated correctly. They had replaced alternators, batteries, and a voltage regulator, all to no avail. I fixed it in about ten minutes at no expense.
My point is that service organizations are primarily in business to make a quick buck, not to do good work or even effect a repair. Just take the money and run.
Good point on the voltage. Got a lifetime alternator from Shucks several times. But I think it was rocks into the lens. Most were the left side. Now that O'Reilly has bought out Shucks the life time warranty isn't much good. Oh! I also finally replaced the starter after years of growling. So the other day it did not want to start but I could see the lights went dim. Time for the bonking stick — well had to use the crescent wrench I use for the drain plug on the boat. Tap tap and cranks right up. Same problem with the '00 Cavalier. Only used the WIFE's cane (actually its mine). Boink boink starts right up. Gee must have been the cold weather.
Learning to turn the ignition on in the Model A before cranking. Well, it needed a charge of mixture any way. Now there the voltage is critical. Its still 6v but has an alternator and halogen head lights. Just fixed a couple of wiring errors. One was the instrument lights on the parking light in the head light. Only worked in parking. Changed it to the tail parking — running light.
If lights keep burning out the usual reason is the voltage regulator in the alternator is set too high a 12 volt system may charge at 13.8 to 14.2 but NO HIGHER. At 15 the battery life is shortened and lamps life is 3 months but at 13.8 lamp life reaches 5 years...The headlights being on continously at high rpm and therefore max voltage are most secespectable to the voltage regular mis adjustment replace the regulator if is is seperate from the alternator or the entire alternator if the regulator is internal and your headlamps will last years.
Radiator caps have three seals...One lets fluid out at 14 to 16 psi. one lets fluid back in from the overflow tank, and the third seals the top of the cap to the top of the neck to direct the overflow toward the overflow tank and holds a vacuum so the cooling engine can draw the contents back into the radiator and "Top-it-off" each time you shut the engine off. In the old days radiators ran a couple of inches low for expansion but now their kept tight full.
Dealer service is mostly parts replacement today. A friend bought a NON-waranteed used car, a week later it wouldn't start, the wrecker came and took it to the dealer's shop. They replaced the battery. $75... a week later it wouldn't start "Ditto" and they replaced the alternator. $150...a week it wouldn't start "Ditto" and they replaced the starter. $200 ... Still running a year later. She asked the service about the Batteery and alternator that did not fix the problem... Reply, "They were 'weak' " In consumer service we call that "Shotgun" service, just keep trying until the sympton goes away.. In my opinion, Dealers service is performed by "Parts Changers" not Mechanics!
My HiLux 4X4 Pick-up I bought new '84. I've gone through at least two dozen headlights. Had to change out the fuel filter which the manual does not locate. Put in two clutches because of the big boat I towed. The water pumps kept failing probably from over tight belts. But when I put in a factory water pump have had no problems. The engine cracked a sleeve around 175K. Had a used Japanese engine put in w new clutch and now I have about a quarter million miles on the frame. Had to replace one emissions part a vacuum actuated electrically held valve. The emissions equipment is shot now but it does not matter as it is older that 24 years and does not need to be tested any more. The only down side is people will pull in front of me and slam on their breaks. No ABS in and ABS world is exciting.
While I have the best Mityvac vacuum hand pump available (the metal body one), and use it for my 1991 and other cars succesfully, it is useless for my 2002. This model has such a large cavity in the empty volume inside the ABS valve body, that the air bubble that accumulates there when I perform a complete brake fluid change, that the mighty "Mityvac" is not powerful enough to completely remove the resulting air pocket. That is why better brake repair shops here where I live, have resorted to buy an expensive but excellent machine: the ATE FB30s is a bleeding unit that has a pressure cap that installs over the brake fluid reservoir atop the master cylinder, that feeds fresh fluid maintaining the proper reservoir level while the technician goes around the car opening and closing every wheel cylinder to purge any air bubbles in every line. The pressure is adjusted about two bar (30 PSIG approx).
First the technician uses a vacuum hose to remove almos all the old fluid from the reservoir, and then attaches de cap adaptor, pressurizes the system and manually opens one by one the bleeder crews at the wheels.
The pressure, and specially the VOLUME of fluid that this machine can flow through the lines is more then enough to be able to pull along the large bubbles that my 2002 accumulates.
The owner of tha shop told me that he decided to buy that equipment because they have foung that many recent cars are problematic to service because of complicated ABS, EBS and all sorts of acronims, plus the fact that hydraulic line placement and paths are no longer properly made. (Guess what: the factory uses pressure fluid fillers too!).
Believe me, I've been maintaining my vehicles for decades, by later models are becoming a nighmare to work on them. I'm facing the decision about tackling the timing belt change in my 2002 with 53,000 miles, or to take it to a shhop, because the belt change implies a lot of disassembly in overly tight spaces. And the belt change requires changing the coolant pump, belt tensioner and idler, all are inside the engine, which obligues to remove ALL the accesory belts, pulles, many covers etc. So much for progress and "advanced design".
To make matters worse, the steering rack has started to exhibit some play, so that is makes a metallic noise when the car goes over bumps, and is leaking a little steering fluid too. Now, to remove the steering rack from the car is not easy at all, requirin to remove the whole front subframe... In comparison, my older 1991 has twice the years and over twice the mileage and has no problems like these.
Now this perfectly fits into the description of monkey-designed products. I blame it squarely on automation on steroids, a very common practice in some countries. Automation should be closely overseen and supervised so that any malfunctions can be identified and corrected in good time before they let any faulty products slip through, as seems to have been the case with your radiator cap.
@Charles, I think you could have done better in addressing the multiple design flaws in the new car. Maybe they were due to the fact that you were buying a used car and some malfunction was to be expected but, as in the case with the radiator cap, it was a genuine manufacturing flaw that should have been brought to the attention of the manufacturers; if only for the sake of other drivers who may have similar issues.
Amclaussen wrote "the only service I remember that I HAD to order in the last years, was a brake system hydraulic fluid purge ("bleeding'), and that is only because present day automotive "engineers" are terrible designers, and had made pedal purging impossible, having placed hydraulic brake lines full of up and down curves and empty ABS valve housings where air accumulates when one changes de brake fluid... and the brake cylinder hasn't enough volume to displace those air bubbles completely, REQUIRING a power flushing device to achieve a COMPLETE air purging)."
You might have been able to purge the brake system using a handheld vacuum pump with a fluid-catching jar. This combination costs about $25 at discount auto parts stores and has many other uses.
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