Hot answers tagged

6

The cruise control on a modern car is totally electronic – obviously it has to interact with the car's controls, but no more so than would happen in "manual" driving. There should be no reason why you can't turn it on or off at will.


5

The coolant ratio does affect how the system cools the engine, but probably not as you'd think. Water is a better thermal conductor than is the antifreeze, so it will do a great job of shedding the heat of the engine. Water by itself does boil sooner than an antifreeze/coolant mix, though, so you could expect it to boil over sooner than without the ...


3

You are right about leaks in that the liquid will flow down from where it leaks at. In your case it is really hard to tell exactly where it's coming from, but would suggest you are right about the valve cover being the source. It usually is a primary source for most leaks of this type. Cleaning off the area was a great first step in figuring this out. With ...


3

I fear you may have jumped several steps at once here. It is likely that a failed or faulty coolant temperature sensor is causing your hot-start issue. As regards the fuel system, this will retain pressure for some time after the vehicle is stopped but the pressure in the fuel lines typically remains fairly constant as it's set by the fuel pump and ...


2

I have VW Golf, which technologically should be similar to Audi, and I observe the same behavior you describe. I think the reason to keep the fuel on is that ECU can keep the speed constant in more cases, than with fuel shut off. Also with cruise control it seems to consume more fuel when you have many uphill/downhills compared if you use throttle manually.


2

A test you can do is to measure the heat from several places: Both upper/lower radiator hoses Both inlet/outlet heater hoses. I'm thinking you may have either a clogged radiator or a bad thermostat. If the thermostat is going bad (sticking closed), you'd most likely see the top radiator hose being a lot cooler than the inlet side heater hose. If the ...


2

Pull all your spark plugs, careful not to mix them up in reference to which cylinder they were IN. Are ALL of them as BAD as That one you show us here? IF that plug is the darkest, IS IT FROM THE CYLINDER that your FUEL PRESSURE REGULATOR gets its vacuum suction from on the INTAKE RUNNER feeding that dark over fueled spark plug. HINT undo the vacuum hose ...


2

Fuel Rail Pressure was around 6 bar when off (25 bar when on, 70+ bar at WOT), it remained this even after 2 hours (I'm guessing it primes when you turn on the ignition) I believe this is the root of your problem. The fuel rail needs to maintain a certain pressure so that the vehicle can start up with the engine hot. If the pressure isn't high enough, the ...


1

NGK is backwards with heat range, meaning the lower the numeric digit is, the hotter the NGK plug is. This is unlike every other spark plug where you get colder in heat range when the number is lower. So if you seek a band aid till you figure the problem out.. place a hotter plug in just the holes that show carbon deposits on the plugs, so it won't foul ...


1

From what you posted in your question, this would seem to me to be something in the HVAC system which is vacuum operated (taking a stab at this). Since it is not dependent upon engine speed for the noise (you stated the noise increased speed while the engine itself remained at idle). You also stated you can only hear it from inside the cabin. My thinking is,...


Only top voted, non community-wiki answers of a minimum length are eligible