I have a 1999 a4 1.8t and my brother took it to MN from WI. I got my keys back this mourning and took it out for a drive. I look at the tach and the rpm idle goes from 900 to 400 then increases to 1400 and settles down at 800. I took it out for a drive to see. I hit the gas it bog and feels like its going to shut off but then it goes. I shift and gas it again and it bogs.the check engine light is also on and my car louder now. my brother told me, they were driving and the check engine light came on. i am clueless as to what is causing this. help please.

 

Go to advance auto or autozone tell them to read your car and then post the code back on here... Someone with vag-com will let you know exactly whats the problem instead of jumping around to different things...

 

is the check engine on or flashing

 

Does it have any trouble starting?

Josh

 

if it flashing that means your having reatime missfire. this could be as easy an cheapas a coil or it could be your spark controll mod. just as easy but a little more expspensive let us know. hope this in was helpfull you still need to have the codes pulled it may have jumped time

 

it sounds either like you have a misfire, or more probably (because you said its louder) you have a leak somewhere after the mass air sensor and the TB. check the hose going from the intake piping to the diverter valve. on my car that hose is rediculously close to the A/C belt and it rubs thru the hose every now and again. i zip tied it out of the way to somewhere on the radiator.

 

I think it's your coolant temp sensor. It can cause ALL kinds of problems, including misfires. I would try buying the CTS, it's like $10-$15 from the dealer and its an easy fix. Try that out first.

Josh

P.S. Also get the codes first.

 

thanks guys you guys are really helpful I'll go to advance tomorrow and get the codes.

 

ok I got the codes they are:

p1127-Manufacturer control fuel system metering

p1545-Manufacturer control veh speed Idle speed control