problems with cold start with the V10

[DrDavid121]

I have a 2011 R8 v10 with 1200 miles. I've notice diminished throttle response upon cold starts. This feels like fuel starvation or loss of compression. The problem resolves itself within less than a minute but nevertheless annoying. The problem only occurs on cold starts. The dealer contacted Audi of North America and they acknowledges the problem and trace it to the harness. Thus far they have not taken action but the problem is under investigation. Any folks out there with similar problems?

DrDavid121

[NVRL8R8]

Diminished throttle response upon cold starts? Not sure I understand the "problem" here. Are you starting vehicle and immediately pulling away before the 1 minute you say the issue diminishes?
I won't move my car at least until the cold start idle, idles back down to the normal or "idle" speed.

[DrDavid121]

I allow the car to idle throught the "cold start" phase, once the rpm's drop and I pull away the car boggs down momentarily. Audi acknowledges the problem and traces it to the wiring harness. Waiting a response the Audi engineers at Audi of North America.

DrDavid121

[willyjp]

The engine (fuel, ignition, valve timing) management is, of course, totally mediated by electronics and therefore electrical bad connections and glitches (one mechanic once referred to an intermittent electrical problem I had in another car as, "like a pinched nerve!!") are probably always the first place to look in this kind of thing; either that or a faulty sensor (of some parameter). Fortunately, most of these things are self reporting and fault codes show up when they connect to your car. He's probably telling you that he pulled codes compatible with a conduction problem in some circuit. That would then be the default first place to look.

[emaN laeR]

Why not get the Ross-Tech VCDS and acquire a complete scan and see what the fault codes are. It's simple and quite powerful to use.
At least a fault can guide you to what the dealer is talking about.
One more mention and haven't said it enough, use the BEST quality fuel available. Any traces of ethanol will damage the fuel system and the engine management system will adjust quite poorly using low quality fuels.

[feudal serf]

Why not get the Ross-Tech VCDS and acquire a complete scan and see what the fault codes are. It's simple and quite powerful to use.
At least a fault can guide you to what the dealer is talking about.
One more mention and haven't said it enough, use the BEST quality fuel available. Any traces of ethanol will damage the fuel system and the engine management system will adjust quite poorly using low quality fuels.

Agreed.
Plenty here posted about the DFI engines.
I had similar trouble and now on my second bottle of this stuff:
http://www.bardahl.com/mods/gallery/...&box=&shownew=

Used one bottle every 3 tanks. Starts and idles perfect.

Fuel quality and consistency are a must for these engines. I purchased my car used with 5K miles. I noticed the problem after i refuelled at a place I don't frequent. I decided that I will refuel at the same high volume station from now on.

Cheers
FS

[willyjp]

Any traces of ethanol will damage the fuel system and the engine management system will adjust quite poorly using low quality fuels.

I agree it's bad stuff, but that might be a BIT overstated. Per the manual, the car is certified and warranted to handle up to E10 without problems (of course, not the water that might come with it!). In some localities in the US you simply can NOT buy non-ethanol blended fuel. In the city where I live that was true until just very recently. In just the past few months, we can now get E-free premium, but my R8 ran fine on E10 premium (Chevron, which is a "top tier" and has injector cleaners) for 2 years.

I'd be fine with getting rid of it, but no point stoking an ethanol phobia, especially if someone's in the position of having no choice.

[emaN laeR]

Politely, I don't tend to overstate the facts, especially when it's tested and known to cause issues. This is what I teach and know how ethanol behaves, especially in a performance engine. Get this document and read up on the testing:
http://www.esatinc.ca/News_Letters/E...ol_Testing.pdf

One other matter that is not known or discussed, the flash software in Europe is far different than what is current in North American models. The reasoning is better quality fuels and oils that the Euro market demands.

[willyjp]

Politely, I don't tend to overstate the facts, especially when it's tested and known to cause issues. This is what I teach and know how ethanol behaves, especially in a performance engine. Get this document and read up on the testing:
http://www.esatinc.ca/News_Letters/E...ol_Testing.pdf

One other matter that is not known or discussed, the flash software in Europe is far different than what is current in North American models. The reasoning is better quality fuels and oils that the Euro market demands.

Well, as I read your submitted document, it warns against EtOH content HIGHER than 10%. I was commenting on your statement that "any trace of ethanol will damage the fuel system", which I'm sure you would agree must not be so....or Audi wouldn't warranty the car for use with fuel with up to 10% EtOH content.

Don't misunderstand me, I personally think ethanol is a HUGE problem with internal comustion engines and I would NEVER use fuel containing it if I had the choice; I was merely pointing out that there was no need for any R8 driver to stop driving their cars for fear of damage if they had no way of obtaining fuel without 10% ethanol. I quite agree a higher content would be very inadvisable.

[emaN laeR]

The document is more or less and industry standard for ethanol use and also a way to test the fuel quality. The issues that I see in many circumstances is the damage noticed after long time use. I also know that many components are re-engineered to accept the use of EtOH. I do agree that EtOH is a problem not really noticed as much for low performance engines but so happens the high performance engines suffer greatly and earlier. I try to advise customers and repair facilities to "convince" the daily driver to "invest" in products that maintain those systems to a greater degree.
One other point is while in diagnosis, erroneous readings can be viewed and a times has lead to misdiagnosis when the system is trying to trim fuel and air mixtures of less than optimal for the design. Here, there is a choice and fortunate that I can purchase "more bang for the buck"
My comment and warning about the use of EtOH comes from multiple issues, including replacement components that are expensive and time intensive for service. I see theses issues quite different from state to state, depending on the percentage of EtOH.
When dealers stock multiple injection devices, I question the reliability of such devices as compared to dealers in Europe. When it comes to an R8 and noting its expense, Audi AG isn't going to question fuel quality as a possible issue when they have a bottom line as to how many get imported into North America. My opinion and share your as well.