i have been looking for something to leaed me in the right direction for hours and can not find a thing so here i am posting my first thread.....

i have a 1998 a4 b5 1.8t with a few mods:front mount, rear sway bar, drilled and slotted brakes with hps pads, blow off and 2.5 all the way back with a test pipe(cheek engine light is on becasue i wont pass smogg)(runs really richnever getting a test pipe again)

so i was drinving my car down the highway and bam my car looses all power and my oil light flashes and it completly shuts down........

i thought it was something really bad becasue if an oil light comes on and your car takes a **** than that is a pritty good indicator that your fucked

so i proceed to cheek the oil level and everything is ok so i jump back in my car and start it and drive home........wtf??????

i am driving the next day and it happens to me again..... i than start to take notice to my cheek engine light this time. it is allways on and the onley cell it gives is for me not having a cat. so this time when it died the cheek ingine light fluttered and than shut off.... i turned the ignition off and than back to the on position and the light was still off. i than waited for a while with the ignition on and the light majicly came back on.

when you turn your ignition to the on position before the start position the cheek engine light should be on.....but mine is not......and than sometimes it is on.....when it is off it will not start but when it is on it will start..... i need help i cant figure this one out please give me any ideas

 

first you need to get your codes pulled. and not at autozone. go to the dealer and tell them to just get the codes for you. they may not even charge you for it.

a test pipe doesnt cause you to run rich. also do you have a wideband a/f gauge so you know it is actualy running rich? you could be running lean and the engine was knocking which is why it shut down to protect itself.

what is the code exactly? i know the code scanner didnt just say "P10xxx - you dont have a damn cat."

the car doesnt magicly do stuff (with the exception of phantom tiptronics) get it scanned by a dealer or someone with vag com, sometimes the autozone free scan is good enough to get an idea whats the problem, sometimes its WAYYYY off.

 

i know for a fact that it is runing rich my gas millage has gone down and there is allways black soot on my bumper and i can smell the fuell. the cat code it threw was p0175 the other two codes that my scanner does not have a discription for is p1127 and p1137

 

double post

 

The oil light will flicker when the car is stalling out due to poor oil pressure.

P1127 is long term fuel trim, too rich off idle (multi)
P1137 is long term fuel trim, too rich at idle (add)
P0175 is generic OBDII code for rich condition

None of these would really pertain to your test pipe.

Likely causes of a rich condition are an MAF reading too high or a bad ECT. If your car is running pig-rich, it will stall randomly.

 

Don't forget that the rich conditions will be helped along by the fact that he's running a blowoff valve - every shift is dumping excess unburned fuel through the system, which is being seen by the O2 sensors.

To the original poster - get rid of the blowoff valve and get an aftermarket diverter valve - our cars are NOT happy when running those things, and the rich spiking will eventually frig up your O2 sensors (as well as the cat if you had one). Depending on how long you've had it, you may have already carboned the hell out of the primary O2 sensor, to the point that it isn't reliable enough for the ECU to trust with fuel mixture trimming. That could be a reason why you're running so rich - when the O2 sensor goes south, the ECU reverts to pre-programmed fueling maps that are intentionally rich to protect the motor.

Deep-six the BOV, check your primary O2 sensor's condition (and change it if need be), ditto that for the spark plugs, and then see what happens to the way your car runs.

 

some people run BOVs without problems. if your car is running 100% fine, it wont mind running rich for a split second durring a shift. the ecu will even learn to avoid it by adjusting the fuel for it slightly. however some people have major problems with BOVs and if you are running overly rich in the first place and the ecu already cannot adapt to it, a blowoff valve is just adding fuel to the fire. literaly.

its a good idea to swap it with a DV and see what happens. you probably have a failing o2 sensor or a decent size leak somewhere in the intake. do you have a boost gauge? how much vacume are you pulling at idle and when the engine is above 2500 rpm and you take your foot off the gas?

http://wiki.ross-tech.com/index.php/16559/P0175

 

if the cel is not comming on when you turn the key on then your ecu may be going bad I know when my ecu whent bad the cel would not come on when I turned the key on hope this help.

 

Agreed with Ghost that anything can happen, but the majority of people who try running atmospheric dump valves tend to have problems from what I've read. As to the leak that Ghost mentioned, take a look at the flexpipe - I know Hiwords had a nasty hole in his, and although the car sounded great, I'm sure it wasn't doing him any favors at the gas station.

 

ok....... thank you for the help so much

as far as my vaccum at iddle it reads 15 and when letting off the gas it reads around 20.

i have someone that i can switch my ecu out with to see if that is it


as far as the bov i had it on for several months and had no problem with runing rich but as soon as i put my test pipe on it seemed to gradyally get richer and richer.....but i have also been told about it making it run rich but like that other guy said some people have problems and others dont

is there any way for me to clean my o2 sensors??

i will try the ecu asap and let you know whats going on and i will take a look at the plugs and the o2 to see if the are black as hell.....