So I wanted to share this scenario which I had previously attributed to my Hobbes switch activating the w/m injection at an inopportune time during part-throttle acceleration.
I believe that part of the problem comes from me having possibly slightly too small a k&n filter on the holset inlet due to space constraints. I guess I should've cleaned it last month when I thought my 2nd IAT sensor was breaking down in front of my eyes.
Symptoms were, when intake temps reached the 25 to 30 C area, the IAT sensor would read dramatic swings between 10 and 30 C several times per second. The result was strangely a lean fueling event that caused a lack of power. I cleaned the first sensor last month that showed the symptoms before installing it Saturday. The sensor that came out Saturday was showing the same symptoms of course.
After I changed the sensor out I decided to clean the nasty k&n for good measure. Problem solved lol. Glad it wasn't my engine prematurely eating those IAT sensors though!
VEMS dirty 1.8t IAT sensor symptoms
VEMS dirty 1.8t IAT sensor symptoms
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
Re: VEMS dirty 1.8t IAT sensor symptoms
Are you oiling the filters? Don't.
Matt
18 Silverado 1500 work pig, roof rack and tonneau cover
11 Jetta sedan TDI DSG, rear muffler delete
GONE :( 87 4ktq - 4 FOX SNAKES

18 Silverado 1500 work pig, roof rack and tonneau cover
11 Jetta sedan TDI DSG, rear muffler delete
GONE :( 87 4ktq - 4 FOX SNAKES

Re: VEMS dirty 1.8t IAT sensor symptoms
Yes I do but the problem has ceased since the cleaning but I suppose time will tell (a week?) If the oil messes with it again. That's what you're referring to I think anyway.
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
-
UrSobsessed
- Posts: 286
- Joined: Wed Feb 27, 2013 3:07 pm
Re: VEMS dirty 1.8t IAT sensor symptoms
Oil on those type of filters will cause the kind of thing you're talking about. It happens over time, more so when the filter is over oiled. I stopped running oiled filters on my vehicles because of this kind of thing.
Re: VEMS dirty 1.8t IAT sensor symptoms
Yep. There's lots of other options, although I understand k&n is available literally anywhere. A nice oilless AEM is what we used on Dad's build. They also have dealers all over the place.
Matt
18 Silverado 1500 work pig, roof rack and tonneau cover
11 Jetta sedan TDI DSG, rear muffler delete
GONE :( 87 4ktq - 4 FOX SNAKES

18 Silverado 1500 work pig, roof rack and tonneau cover
11 Jetta sedan TDI DSG, rear muffler delete
GONE :( 87 4ktq - 4 FOX SNAKES

Re: VEMS dirty 1.8t IAT sensor symptoms
Sounds good. I guess until I can find something dry I'll just clean up the IAT like twice a month or thrice. Thanks for the warning guys 

1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
Re: VEMS dirty 1.8t IAT sensor symptoms
I'm confused. I've gotten several emails last 48 hrs saying my threads have replies. No new replies

1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
Re: VEMS dirty 1.8t IAT sensor symptoms
Lots of spam posts that have been deleted.88a5tq wrote:I'm confused. I've gotten several emails last 48 hrs saying my threads have replies. No new replies![]()
"If you can't find one, make one"
Dallastown, PA
1991 Audi 80 quattro (20vt project)
1991 Audi Coupe Quattro (project: my first 20v)
2007 Mitsubishi Raider(Dakota in disguise)
2019 Chevy Cruze RS hatch (wife's little red sporty car)
Dallastown, PA
1991 Audi 80 quattro (20vt project)
1991 Audi Coupe Quattro (project: my first 20v)
2007 Mitsubishi Raider(Dakota in disguise)
2019 Chevy Cruze RS hatch (wife's little red sporty car)
Re: VEMS dirty 1.8t IAT sensor symptoms
Nice! I'm satisfied lol
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ