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Rough running 190e

This car is driving me nuts lately. It all started with a rough idle. This made me realize some high resistance in the plug boot as well as the distri- butor cap (whoever came up with the idea of burying resistors should be...) Now, with new bosch super copper plugs and cleaned rotor/cap with 2.4k resistance (OK, 1.2k in one branch) the car idles reasonable (not perfect) and on stepping on the gas gently will accelerate smoothly. Push on the gas to quickly and it will stutter and then smoothen out at higher rpm... what the heck is going on???

cheers, guenter

Reply to
Guenter Scholz
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2.4k ohm on the spark plug wires are way too high... I am not sure what you meant by 1.2k in one branch...
Reply to
Tiger

Tiger, there is a 1.2k ohm resistor buried in both the boot of the plug and in the distributor cap housing in each contact point. One of these resistors went bad so I drilled it out and short circuited this contact point with a screw. Therefore in one circuit (branch) the total resistance is 1.2k rather thatn 2.4k. I seem to remember reading somewhere that this is a bit of redundancy to make sure there is always 'some' resistance in the circuit in case there is a short circuited somewhere (presumably the ignition module is unhappy with a short).

cheers, guenter

ps I'm about to check to fuel filter.... never know.

Reply to
Guenter Scholz

Not to my knowledge... there is only one resistor at the spark plug end.

1000 ohm. Nothing at distributor end.

Theoretically... there is no possibility of short circuit... that thick insulation prevents that... and resistor... well, if it goes bad, it will only increase in resistance.

I have done so many spark plug wires... they are all1000 ohm new.

Reply to
Tiger

Tiger,

Yes, there is 1k from plug boot to the end of the ignition wire (the 1k is in the boot). I addition there is another 1k resistance in the feed- through from the top of distributor cap to the inside rotor contact. Moreover there is yet one more 1k resistance in the feed through on cap from the ignition coil. So, from ignition coil there is a total of 3k resistance to each spark plug. The latter 1k is primarily for RF supression I think.

cheers, guenter

ps that's why that distributor cap is so darn expensive....

Reply to
Guenter Scholz

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