Car question

[glatt]

Not yet. I've been too busy.

[xoxoxoBruce]

I'd be looking at the battery and it's connections. the headlight idea is a good place to start, then Pep Boys, Autozone, or one of them, will do a reserve test on it for free. You don't have to take the car, just the battery. You could also try jumping it with your car.

The electrical architecture on newer cars is a nightmare. When they started running signals on the same wire as power it became infinitely more difficult. Every car I've owned I've bought the factory repair manual, but starting with the Chevy manual for my 2006, half the diagnostics say hook up the dealers computer, that costs damn near as much as the car, and walk through these steps. So after this muti-grand computer beeps and whirrs, and bops, it's says, check for a loose gas cap. WTF, couldn't you just tell me that up front?

[Griff]

and you mock my need for an old CJ.

[tw]

Or get the little code reader for about $100. It works on all cars. Cars today with the computer as so much easier to fix as compared to 1960 and 1970 monsters. But that means a $100 tool - that works on all cars including Chevy.

[xoxoxoBruce]

Code readers are wonderful, tells you what system the problem is probably in, although sometimes there's some overlap. However that's not the same a fixing it. OK here's one I've had, P0442 OBD-II Trouble Code. my code reader told me the code p0442 was the reason the check engine light was on, cool. By the way, p0442 is not exclusive to GM.

p0442 - Evaporative Emission Control System Leak Detected (small leak)
The vehicle's PCM (powertrain control module) tests the evaporative emissions (EVAP) system for large and small leaks among other conditions. In the case of this DTC, it indicates a fuel vapor leak in the EVAP control system. It means a very small leak has been detected. In fact, the leak can be from a hole as small as 0.04" in diameter. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle's fuel system.

OK, find the leak and fix it, that should be simple, no electronical wizardry or anything. Where should I look?

A code P0442 most likely means one or more of the following has happened:
•A loose or improperly affixed gas cap
•A non-conforming gas cap (i.e. not factory/original brand)
•A small leak/hole in a fuel vapor hose/tube
•Other small leak in EVAP system
•Faulty vent o-ring seal
•Defective vent valve
•Defective purge valve
•Defective leak detection pump

Hmm, I can check if the gas cap is tight, but won't know if it faulty. Maybe if I light a match by the gas cap. No, bad move.
Leak in the vapor hose/tube. Well the hose goes from two spots on the tank, up to the engine bay vapor canister. A 0.04" hole, huh?

There's a vent valve and purge valve, one's on the top of the gas tank, between the tank and the body and the other is under the hood in one of the hoses. Wonder which is which, my reader only tells me p0442, and the repair manual says hook it up to the dealer's big buck diagnostic computer. Hmm.

In my case it turned out to be the purge valve that's easy to get at, but no way of knowing whether it's bad or not by looking at it.

Well how about a U1255 OBD Trouble Code?

U1255 - GM
Type Network - Manufacturer Controlled DTC - Manufacturer Controlled

Description Class 2 Communications Malfunction

Cause ECM DTC B with Freeze Frame and Failure Records stored or TOM DTC TCM flashes Sport Mode Indicator, TCM sends a MIL request to the ECM, the ECM illuminates the MIL, TCS is disabled and the TC Indicator is illuminated

Got it? Got it. Good.

[Gravdigr]

Originally Posted by tw

Cars today with the computer as so much easier to fix as compared to 1960 and 1970 monsters.

That's the craziest thing I've read this year.

[glatt]

lol. yeah, I was gonna just let that one go.

Edit: I think it's fair to say that cars are more reliable now and don't need fixing as much as cars back then did. But when they do need fixing, it's exponentially more complicated.

[tw]

Originally Posted by glatt

I think it's fair to say that cars are more reliable now and don't need fixing as much as cars back then did. But when they do need fixing, it's exponentially more complicated.

Actually it is not. Ever try to fix a Pinto? It took multiple part replacements before we finally traced the failure to a cam shaft and then to many burned out diaphragms in the carburetor. Nothing would tell you what was wrong. The solution was to just start replacing parts - ie always start with a tune up.

I have traced failures immediately to a defective part by simply viewing a computer code. For example, fuel injectors were on too long. That was immediately traced to a fuel pump that worked just fine - but had insufficient fuel pressure.

View this My check engine light is on discussion. The computer code said exactly what was wrong. Only problem was a mechanic who could not understand how to see a defect clearly identified by a computer code.

Many problems are not complete failures. Most problems are changes (ie worn camshaft, sticky Idle Air Control valve, etc) that cannot be found without a computer. In one case, a partially obstructed nozzle cause an EGR valve to respond slowly. Computer quickly identified that defect that would only get worse with age.

In days before computers, one car would sometimes knock. It was taken back to a dealer multiple times who could find nothing wrong. It took me quite some times to find her problem. Centrifugal advance and vacuum retard plates inside a distributor were sticking. This could only be observed when the car accelerated and since plates did not always stick. Had a computer existed, this problem would have been identified immediately. Distributor removed, cleaned, and all knocking ended. Sometimes it takes courage to disassemble something as complicated as a distributor especially when it is not your own. It took quite some time of driving, playing games of what if, and eventually removing and disassembling that distributor to find the defect. Computer would have identified it immediately.

Computers have clearly made defects now so easy to identify - in some cases before that defect causes a roadside breakdown. Computers have clearly made auto repair easier as now seen by more reliable cars and even by a reduced number of roadside breakdowns.

[Gravdigr]

Originally Posted by glatt

I think it's fair to say that cars are more reliable now and don't need fixing as much as cars back then did. But when they do need fixing, it's exponentially more complicated.

Agreed, 100%.