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As always when this subject comes up, major props to Chrysler for making the codes easy to get. At least, in the past. Looks like it's not so easy on newer models. (Must be the Daimler folks that are influencing it.) Too bad.

Maddest props to Chrysler for making their diagnostic codes end-user accessible.

Saved me a bundle being able to walk into a good mechanic's shop and saying "Diagnostic code XX, friggin' oxygen sensor."

Here is a link to anECM scanner (a device that will read the diagnostic codes on modern cars) for only about $500. It looks like it can handle a wide variety of Chrysler, Ford and GM vehicles built between 1984 and 1995.

The company sells a few other interesting toys that could be of use to automotive/electronics geeks.

• Miata Engine Computer Self Diagnotics
• Chrysler, Plymouth, and Dodge Computer Fault Codes
• Datalogger a commercial hack from TechnMotive similar to the poster's requrest. There may be other good stuff on the TechnoMotive site.
• An overview of electronic engine control from Intel.

Are you sure it's the engine that's at fault? Or do you not know how to set up a Holley 2245/Carter BBD carburetor?

The Slant-6 was designed in the late 1950s as a race engine to compete with small 6-cylinder cars from Ford and GM. It was a completely aluminum engine, leaned to the passenger side to allow for a tunnel ram intake manifold, lower hood line, and a center of gravity to offset the weight of the driver. In its early incarnations, it was a very short stroke engine, displacing 170 cubic inches, and capable of happlily revving to 8,000 RPM +.

In typical Chrysler do-or-die fashion, in 1960, Ford had the Falcon and GM had the Chevy Corvair. Chyrsler had been playing around with the Valiant, but still didn't have a motor for it. They experimented with their high-tech aluminum block Slant-6, and decided it wasn't durable enough for the masses. On a tight timeline, they poured the Slant-6 with high-nickel iron alloy instead.

It's worth noting that aluminum is much softer than iron. If you're building an engine block out of aluminum, it has to have a huge amount of "webbing" (kinda like flying buttresses to help hold the block together) in order to maintain its rigidity. Since the Slant-6 had been designed for aluminum, it was vast overkill making it in iron.

Produced from 1960 to 1983 (cars), 1987 (trucks), and 1991 (marine), taxi fleets powered by Slant-6 engines have gone literally millions of miles between rebuilds. One of my Slant-6s came to me in a 1974 Plymouth Valiant Brougham. When I got the car, there were 297,000 miles on the odometer. The car had been neglected, and the lifter adjustments - necessary with all older engines with mechanical lifters - hadn't been done. She was running on 4 out of 6 cylinders, but still started and ran well, and would still peel the tires. The engine didn't burn or leak any oil, and aside from a really rough idle and the stench of unburned gasoline leaving through the tailpipe, it still sounded healthy at speed: no bearing knock, *strong* oil pressure, compression of 130PSI on the four good cylinders. I'm still working on restoring that car - the body was pretty cabbaged when I got it, but it's looking a lot better now.

The only Slant-6 with a real achilles heel is the 225 / 3.7L Slant-6, which were the only Slant-6s made after 1972. The 225 Slant-6 has a very long stroke (4.125") which means that they're quite sensitive to being over-revved. They're a massively torquey motor, so if you know how to drive based on torque curves, you won't over-rev it anyway. The failure mode of an over-revved Slant-6 is generally the failure of the number 6 (rear) con rod. I've seen Slant-6s driven thousands of miles with five cylinders running and a broken con rod in the sixth, so it doens't necessarily keep the engine from going. Just be careful if you're downshifting or if you're trying to rock the car out of a snowbank.

That being said, in a Dart, your engine is old enough that it has mechanical valve lifters. You have to adjust your valve clearance regularily - do it just before every oil change. Or, you can replace your cam and lifters with more modern hydraulics. (All post-1980 Slant-6s have hydraulic lifters.) Failure to adjust your valvetrain on any older engine properly is negligence, not a failure on the part of the engine, and it will cost you exhaust valves, especially if you're not running a lead additive. (Slant-6s before 1972, as with most other vintage engines, don't have hardened valve seats because unleaded fuel is a relatively new "innovation".)

If your engine *still* won't run, check your ballast resistor. Blaming your engine for a bad ballast resistor is akin to calling your motherboard a piece of crap because you keep on hooking it up to cheap power supplies. Chrysler has always been known for good drivetrain components, the support systems sometimes leave a little to be desired.

If you don't believe me about the legendary durability of the Slant-6, I invite you to take a look at Yahoo and see what comes up. Check out Tailfins and Allpar, too. If you're *still* not convinced, I'd invite you to e-mail me with the address and details on the car. If you're nearby, I'll happily give you a few bucks for it and haul it off for a good restoration or to be used as a parts car.