Hi, I just bought a '99 audi a4 1.8turbo yesterday. drove a couple miles streets and highway, felt great. the seller said it was going to need a cluster, the fuel gauge was all crazy and the center screen was hazy. it indicates the "service insp". but there was no check engine light on. soo i believed the guy. drove it 30 miles home, went good. next morning it starts drive it for 5 mins shut it off, then it wouldnt start. tried a dozen times nothing. i got gas put it in, started. but the check engine light is now on. drive to advance auto parts to see the code. they were unable to communicate with the ecu. my question to all who know is, could a bad cluster cause the lack of communication??? hopefully this is a common issue that can be easily addressed. thank you

 

try taking your question over to the A4 B5 section. read the stickies first. then try a search.

there are a whole host of "well it could be" things. does it have an aftermarket radio? that is one of the most common things that cause communication problems through the OBD port. You should also see if you can find someone near you with a vagcom to pull the codes for the CEL. center display is a problem.

my initial thoughts are: fuel pump, fuel filter, MAF or vac problem

Willkommen to the forums

good luck

 

i had very much the same ..my gage said half full but my car would not start. it was out of petrol gas. arfter looking at my intank pump i could see it was down to the sender float that had come off and was in the bottom of the tank altho i still have not got a new pump im sure it is that. my engine cheeck light has been on since i brought the car and has never bothered the car at all intill today it started driveing rubish. cutting out at the lights and it was very hard just to get it home.it felt under power and like only half the engine was working. poping and banging all the way back.. then i unpluged air mas and car drives ok. so hopeing once replaced and reset engine light will go off. as for the computer id get someone els to try. not all work the same and maybe the one they used dose not do audi... just a throught. i know theres a bit of a story there. but might be some help best of luck

 

do you try to check engine systems? I advice you the v checker v102, which is suitable for DIY work,easy to use.

 

thanks for the inputs. the scanner they used was wrong. a buddy of mine had one that worked. it had a po118 coolant temp and a p0422 o2sensors. as for the cluster I think its ok. and I do believe it needs a fuel pump sending unit (which once it warms up I'll put in). I replaced the temp sensor, its been running great ever since!! as for the p0422, I just cleared the code, wait to see if it comes back, gonna see if it was a stored code or active.