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Tripod · 03-02-2007, 03:40 PM

Thanks for your ideas. Information is good.

I have had the mis-pleasure of working on Bosch k-jetronic about 25 years ago. I bought an engine-less VW Rabbit from a bankruptcy case and an engine from a salvage yard. Installed the engine, put in some fuel and started it up. Everything was good for about 30 seconds. As it turned out, the gas tank was contaminated with moisture, rust, dirt, etc. After boiling out the tank, flushing the lines, replacing the filter, etc., the fuel system was never really fixed. I replaced the warm-up regulator, adjusted the sensor plate, tested the pressure regulator, checked the amount of fuel flow with each injector, tested the cold start injector as well as several other parameters.

As it turned out, one of the remaining problems was that the vibrating tips in the injectors were so worn that most of them would not hold any pressure after the car was shut off – they continued to drip fuel until all pressure was released. My solution – short of replacing the injectors, was to put a jumper in the fuel relay under the dash and run the fuel pump until the pressure was built back up – you could hear the pump when it reached the point of re-establishing pressure. Then I put the relay back in and the car started immediately.

The problem I have with the Audi is that I can shut off the warm engine and immediately try to restart – and it will not. It will only turn over with no sign of ignition. If this was a bad accumulator or leaky injectors, it seems that it would restart immediately upon shut down. As it is, I can fairly accurately predict when the car will restart based upon ambient air temperature and having the hood open. It is as if a switch is turned on – one minute it will crank with no sign of ignition and then literally the next minute fire right up with no signs of fouling, flooding or any other problem.

Thanks again for the advice, if I ever figure it out I will post the solution.

03-02-2007, 03:40 PM	#3 (permalink)
Tripod Newbie Join Date: Feb 2007 Posts: 11 Gallery: (0)	Thanks for the info.... Thanks for your ideas. Information is good. I have had the mis-pleasure of working on Bosch k-jetronic about 25 years ago. I bought an engine-less VW Rabbit from a bankruptcy case and an engine from a salvage yard. Installed the engine, put in some fuel and started it up. Everything was good for about 30 seconds. As it turned out, the gas tank was contaminated with moisture, rust, dirt, etc. After boiling out the tank, flushing the lines, replacing the filter, etc., the fuel system was never really fixed. I replaced the warm-up regulator, adjusted the sensor plate, tested the pressure regulator, checked the amount of fuel flow with each injector, tested the cold start injector as well as several other parameters. As it turned out, one of the remaining problems was that the vibrating tips in the injectors were so worn that most of them would not hold any pressure after the car was shut off – they continued to drip fuel until all pressure was released. My solution – short of replacing the injectors, was to put a jumper in the fuel relay under the dash and run the fuel pump until the pressure was built back up – you could hear the pump when it reached the point of re-establishing pressure. Then I put the relay back in and the car started immediately. The problem I have with the Audi is that I can shut off the warm engine and immediately try to restart – and it will not. It will only turn over with no sign of ignition. If this was a bad accumulator or leaky injectors, it seems that it would restart immediately upon shut down. As it is, I can fairly accurately predict when the car will restart based upon ambient air temperature and having the hood open. It is as if a switch is turned on – one minute it will crank with no sign of ignition and then literally the next minute fire right up with no signs of fouling, flooding or any other problem. Thanks again for the advice, if I ever figure it out I will post the solution.