I took my 1998 A4 (non turbo) to a shop as the check engine light came on and the car stumbles under accelleration...so I figured they can plug into their computer, get the problem codes right...wrong. They could not get their computer and the A4 to "talk" to each other. In fact there was no communication at all.

What the hell is going on? Could there be an issue with the plug that links them together or is there a known problem that would cause this.

The car stumbles when under accelleration, such as passing a car or jumping on the freeway; don't know if its a fuel, electrical, issue but would like to get this fixed.

 

bad fuse?
is the ABS light on?

 

no blown fuses...and yes the ABS light is on; I understand that to be due to a bad sensor. I'm equally worried that the shop is unable to get their equipment to communicate with the car's computer.

 

Sometimes, an after market head unit can cause problems with code reading.

 

Pull the abs fuse and try again, after that i'd look at the k-line fuse in the back of the head unit

 

I know advanced hasnt been able to scan my car before with my ABS bad.

 

I've got a similar problem. ABS light and brake light come on at startup, beeps three times and then continue to flash. At first, we thought it was the left front abs sensor. Now, the Snap-On computer can't communicate with the abs unit. Looks like there is no power to fuses S13 and S18.

Any ideas? Please?

 

ABS module - look for a rebuilt one or get yours rebuilt

 

I'm going to take your advice and get mine rebuilt....I don't have a book but I thought the module was located under the rear seat...but it's not. The only thing under the seat is the Alarm module.

Any idea where the module is?