View Full Version : 1.8t Won't Stop Going Into Limp Mode (4lbs of boost)

10-27-2015, 12:47 PM
2001 Audi a4 with a 1.8t. Was only boosting 4lbs. I did a boost leak test and found two leaks. Fixed, re-connected the battery and it ran great for 15 minutes, boosting up to 9/10 lbs. Then it randomly hit limp mode again, only boosting to 4lbs.. No check engine light, nothing... What's going on..?

10-27-2015, 01:04 PM
You have to check the codes with VCDS. Lack of Check Engine Light illumination does not necessarily mean no codes.

10-27-2015, 01:06 PM
Will VCDS tell me if theres a boost leak?

Wrath And Tears
10-27-2015, 02:01 PM
Yes, as long as you know what to look for and how to look at it. There are so many threads about how to use VCDS as well as google and the ross-tech wiki.

A boost leak wouldn't cause limp mode as far as I know, over boosting does though. I assume you have a boost gauge, what are you reading at idle?

10-27-2015, 02:53 PM
VCDS tells all. Now let's see some codes. [;)]