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1984 1.2 - pierburg 1b fault - any ideas? - 2door
Help! My Nova 1.2 has started exhibiting an odd fault - I'm pretty sure it's the carb as the distributor was recently replaced and there's no tell tale rev counter flicking etc.

Basically, about half the time, the car's idle goes up to about 1000rpm from the usual 800 ish. When this happens and you're driving along, there's a big reduction in performance and the car struggles to accelerate, usually in a jerky fashion. Then, when you're up to say 60-70, and take your foot off the throttle and put it back on, there's a big flat spotty sort of jerk rather than smooth take-up. Sometimes going up a hill it's difficult to keep the car going at even 60mph.

Fuel economy is unaffected, it's still 45-ish to the gallon regardless. The problem comes and goes. Usually it lasts for a couple of hundred miles before going again. I wonder if it's a bit of dirt floating about inside the carb or maybe that pump diaphragm, though that usually affects the fuel consumption as well. Any ideas of what I should be looking for when I strip down the carb?
Cheers
Steve

Edited by Webmaster on 16/03/2008 at 12:05

1984 Nova 1.2 - pierburg 1b fault - any ideas? - Number_Cruncher
If I remember correctly (it's over 15 years ago since I last had one of these apart!), it's difficult to imagine a more easy job than to strip and clean one of these carbs.

You're looking for any signs of dirt at all. Take plenty of time to blow through all the jets and passages with an aerosol carb cleaner - preferably one that has a plastic tube on the valve that allows you to direct the jet of fuild into the jet or passage.

If you do find lots of dirt, then,

a) fit an inline filter in the fuel line to make sure that no more bits get into the carb

b) find the problem - it's either the tank or filler pipe rotting, or the rubber fuel pipes rotting from the inside out.