RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

Thank you for your advice, I will talk with the mechanic and see what they say. I appreciate all the feedback I have received on this forum, and if anyone has any further input I am happy to receive it.
Thanks again all.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

I am having a somewhat similar problem. I have an 2000 A6 2.8 automatic.The car has about 120,000 miles. I too want to sell it, but want to get the problem fixed first. I live at the beach in SC and there is not an audi dealership within 2 or 3 hours, so I have had 2 different mechanics that work on foreign car check it outwith no success.The sensors come up pointing to cat converter or O2 sensors.Both shopschecked the codes and 1 looked at the o2 sensors and did not think this was the root cause.
The car will crank with no problem first thing in the morning. Then sometimes (every day or two) later in the day, the car will not crank on the first try, sometimes it may take 15 minutes before it will crank- althoughthe engine is turning over fine. The happened for a several weeks.
Then ...once I started driving about 5-10 minutes, the car will stall (not all of the time, but the problem seems to gradually happen more and more or the past several weeks). It has stalled several times as I was approaching a stop sign/ stop light. And once or twice when I was driving, (under 30-40 mph). May crank right back up, but usually takes at least 10 minutes.
When I drive long distance on the highway or onback roads, I have no problem. This only happens in traffic or neighborhoods.
After it stalled the first time, I though my battery was going dead, so I had it replaced. No problem for a day or two, then the problem started again.
Also, sometimes when It will not crank, it sounds like something behindthe area of the radio/ cd/ air condition is making a muffled clicking noise.
Any suggestions as to what the proplem may be.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

If all cylinders werent firing, hed have a blinking CEL. Sounds like a bad engine coolant temp sensor. It would be good to replace that and the plugs if you dont know when the plugs have been replaced last, if ever.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

Woulda bad engine coolant temp sensor cause the car to stall while driving, 30 mph? Could it be the mass airflow sensor, or are those two related. If it is a sensor problem, should a local shop be able to replace them?

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

sarah062381: Sounds like the car is flooding. This will cause hard starts and smoke or a gas smell when it does start. And since it only happens when the engine is warmish (left off for 1-4 hours) but is fine when cold, chances are it's the coolant temperature sensor. This sensor tells the ECU (computer) the temperature of the engine, and it injects the appropriate amount of fuel to start the engine based on the temperature. If the sensor is telling the computer the engine is cold when it isn't, the computer will inject too much fuel and it'll flood.

Next time it happens, try cranking the engine with the pedal all the way to the floor. This should clear the flood more quickly.

Does your temperature gauge work properly?

beach54321: Your problem could be temperature sensor related as well. But if you're throwing O2 sensor codes, get those replaced, at 120K it's probably time to replace them anyway.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

thanks for the reply.One question I have ...How are themass airflowsensor and coolant temp sensor related- and which one (if either) is most likely to cause a car to stall while driving? Also why would it stall only at lower speeds vs on an interstate?

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

Do you have any other driving problems besides the stalling? Does it idle rough, lack power, CEL light on?

The Mass airflow sensor and coolant temp sensor are two different things entirely. The MAF tells the computer how much air is entering the engine, so it knows how much fuel to inject. The CTS tells the computer how cold or warm the engine is. Starting problems are most likely caused by the CTS, and stalling could be the MAF, a vacuum leak, or a fuel delivery problem. When did you last have your fuel filter replaced?

When it stalls, is it usually when you're letting off the gas, say when coasting to a stop? Or does it happen when cruising or accelerating?

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

Stalling and the occational cranking problem...the two seem to be related?The check engine light is on, but the car does not idle rough and seems to run fine otherwise. Not sure about the fuel filter.
It stalls when when cruising at low speed (30mph) and/or when coming to a stop. But I don't think when accelerating. When it does stall, it does not jerk or anything....the power steering goes out and it begins to coast to a stop. It has also stall at a gas station while in park- if I leaved the car running to go inside a get a drink or something.I come back and the car is on, but not running.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

Go to Autozone. Have them scan your ecu for fault codes, they can print them out for you. Post them up.

RE: 1996 Audi A4 Intermittent Starting Problem Help!!
 

In case any of you are having similar symptoms, the problem ended up being the crank shaft sensor.