squidix9

Ok, bizarre...

Yesterday I replaced all the vacuum lines on my C5 A6 AHA. They were pretty dry and brittle and I noticed some rough throttle response. Immediately I noticed it ran much better. Everything seemed good. When I got back home I noticed the check engine light was on. I can't say I noticed when it came on.

I ran a scan and found it had a secondary air flow problem. I supposed I had purged the vacuum lines and it was just a blip due the changes. I cleared the codes and took it for a test drive. It still ran great so I was happy. I drove around monitoring readiness and everything set but the SAI and EVAP. I didn't drive long enough.

Today I drove around a lot and it still runs great, so that's a plus. I am teaching my son about auto repair and wanted to check readiness anyway so I brought the computer out to give him a demo.

Firstly VCDS (805) won't give me any selections under generic OBDII to read data. The drop down lists are blank. When I try to examine readiness it keeps rolling the screen over as if it's refreshing it at a rate of maybe every 2-3 seconds. But worse I now have a MIL again, but no codes.

Here is where I am supposed to post my results, but I can't do that either. When I go to the Ross Tech directory it shows it has about 9mb worth of files, but I can't get to them. I did a global search on the file names I used and it can't find them. After saving, I opened and viewed from the prompt box, but now they are gone.

Secondly I do an autoscan to find the MIL and all I get is the implausible signal from the brake switch because forgot to press the brake since I was only doing a demo for my son. No codes, yet I get a MIL. So I went back to generic OBDII and did a readiness check and it passes yet shows the MIL is on.

I have the results of both of these but I can't post them till I can get to them.

Advice?

bearthebruce

How recently did you update version 805? There have been some minor updates that may effect this.

Else, I really think you need to talk with us while in front of the computer and in the car because that is some strange behavior.

I am assuming that you are registered VAG-COM user and bought your interface from Ross-Tech since you are running version 805.

If all that is true, can you call us tomorrow? 267-638-2300 and select the option for Tech Support. Andy or Santos will probably pick up.

squidix9

I just took a trip to the store and with VCDS disconnected I no longer have a MIL.

squidix9

I had 704 and when I fired it up yesterday to check out the cause of the MIL it advised me there was an update available. So I just did it then.

It is strange! When I used it yesterday it worked fine. While I was driving around to set readiness I was watching STFT to see if there were still any leaks and it read data fine. It was still running ever so slightly lean at +2 to +3%, but that's pretty darn good. So it was working 24 hours ago. Also the readiness area in the window was stable.

The only difference between yesterday and today is 24 hours.

squidix9

I took the VCDS to the shop today. I decided to try it on one of the trucks and it actualy worked. So add an '03 Dodge RAM 2500 diesel to the list of vehicles it works with. And it worked fine, much faster than on the A6. The Generic OBD II function worked well and it read all available data.

I then hooked it back up to the A6 and it behaved as before. Under Read Data the are no values in the drop down list and the Readiness keeps cycling.

I uninstalled 805 and reinstalled 704 and it works just fine. Much quicker than 805 and all functions work.

I was busy rebuilding an MC1 today but will try and get on the phone tomorrow.