i have been having some trouble with how my 87 iroc 305 tpi runs..or doesn't run (most of the time). i read somewhere that "over oiling" your air filters will cause the maf sensor to mess up. has anyone heard of this? and if so, is there something i can do to remedy the problem? i am not sure that is my problem but would like to eliminate it as a possibility.
thanks!

 

I've heard the same thing. Is what happens is that when the engine running, the pull of air in the intake sucks up the oil in the filter and coats the maf element and gives a bad reading. I've also heard that it can damage the maf also. I did run k&n's in my iroc a long time ago and my maf went bad when I was using them. Now I just use regular filters so if that was the problem, it won't happen again.

 

This is 100% true and it is also one of the main reasons I discredit
de-screening MAF sensors for performance reasons.


Any codes? I do not reccomend trying to clean the wires in the MAF
or spraying any kind of contact cleaner in it, as it could worsen.

The only I can really suggest is hope your MAF burn off operation
eventually takes care of the problem. Long shot I know, but anything
else is very risky.

Try to drive the car, or even let it idle (if it does) and turn it off
and start it again. You can literally hear the burn off relay as it operates.
Hopefully ..it will burn of the contaminates..

You could try to unplug the MAF and see if the car changes in behavior.

 

i am not getting any codes and will try disconnecting the maf and see what happens. i have no idea if this is why the car is so 'iffy' but when i read about it i thought it could be a possibility.. thanks for the advice.

 

Well you never did say how much oil you used on the K&N's??? If they were dripping oil when you installed them. that may be the problem.
But my guess is you have other problems. For example a vaccum leak or a clogged fuel filter, dirty or not working IAC. And none of these will though a SES code.

 

FWIW, there was a TV show a while back and they did a segment with K&N. This topic was discussed and the K&N rep stated that it would be difficult to over oil a filter and cause a MAF sensor problem. Naturally, they wouldnt say anything negative about their product, but I agree, you would have to have the filter dripping in oil to cause a problem, or have put the oil on the inside of the filter element. I have K&N filters in all of my fuel injected cars and have not had an over oil condition.

 

no it wasn't dripping with oil. i have a k&n on my carburated 68 nova as well and haven't had any problems.. however, when i clean the filters and re-oil i like to make sure there are no 'bare' spots on them.. and i thought maybe i hit it a little too much?? i don't know.

ok.. after rereading george88's post i am thinking that i did in fact oil the wrong side of the filter (an idiot thing to do, i know). i guess my only excuse is that i am new to these cars and wasn't paying close enough attention. at any rate.. suggetions on what i should do?? .. man do i feel stupid.

 

Well, if in fact you did oil the inside of the filter, just remove it, use the cleaner and re-oil. No big deal. I have had a lot of success using an electronic component cleaner on the MAF. However, I would let the MAF burnoff relay try to fix the problem first. A good rule of thumb is to not introduce any more variables than necessary when trouble shooting. With the limited capabilities of OBD I , you can easily get sent down the wrong path and start throwing money at these problems. Dont ask me how I know.

 

i see oiled MAFs pretty regularly behind K&N filters. it doesn't take too much extra oil for it to get on the MAF.
oil on the MAF won't always cause it to set a MAF code. on the newer vehicles, i see mainly lean codes and sometimes codes for the TPS. sometimes there are no codes set, just a performance complaint.
the best thing i have found to clean a dirty MAF sensor is starting fluid.
don't clean it with it plugged in or still on the car. spray it down on the inside & then let it sit for a few minutes to let the either completely evaporate.
do not smoke or use the starting fluid anywhere near an ignition source or indoors.

 

I've noticed on my 87 GTA filter, it is basically a tube & filters from the inside out. Kinda reverse of what one would expect.

I've looked at the filter housing & sure enough, air travels to the "inside", through the filter, then out to the MAF.

So wouldn't re-oiling it on the "inside" be correct?

 

Ive never done so with any of my mine, the filter draws ambient air in
and the red oil helps catch debris, so oiling the inside seemed like a hazard
to me and simply overkill.

Im not sure though.. any luck with car yet?

 

We had this exact problem with our Celica, the oil covered the sensor and made it either run like crap or stall out till it warmed up. Mostly on the really hot days. We took it in for other unrelated service and the place cleaned it up for us and it's run great ever since.

Also had it in my Jeep, and the throttle body was caked with dirt because the oil from the filter created a film and caught all the dust/dirt that made it through the filter. Kinda an oxy-moron really hehe, isn't the filter supposed to catch that?

No more K&N in any of my cars, just not worth the hassle.

 

My point is....You would think my filter would pull air from the outside of the tube, into the center, then in to the MAF. Mine pulls air to the INSIDE, like a straw, then through the element to the outside, then to the MAF.

The filters come oiled NEW & the question is about washing& RE-OILING them.

I made this pic to show what I mean by my "inside out" airflow. Wouldn't it make sense to re-oil it on the "inside"?

 

makes sense to me.. but then again i oiled the wrong side of my filters!

 

I see where your getting at, good sketch too. I dont want to sound like
"you cant" oil the inside of the filter. I presume it would depend on what type
filter element is used and if the car has the factory intake ducting intact.

Since my prior uses have been with the K&N oval cone stand alone type
filter ducted into a CAI.. removed the factory air box to do so, I thought it
was unnecessary to oil them internally.

Ive never had a problem associated with a K&N filter "alone".. excessive
oils though can potentially cause MAF problems. It is better to replace them
after a few oils.. even though they are marketed for long life.

I had a code 33/34 plague my car for 3 months which actually
turned out to be a real problem, similar to your condition! Im glad it
had nothing to do with the K&N filters 'cause I had been using the
same style filters since the rebuild.

 

I have been using the same set of K&N filters for my TPI for the last 15+ years with NO problems. If anyone would read the K&N instructions for Recharging (aka oiling) it clearly states NOT to over oil and air dry before reestalling. Just follow the instuctions and you will not have any problems. My opinion: they are a very good product.

 

For me, I had 2. While I was cleaning/oiling one I would put the other one I had done the last time I swapped them, this resulted in months between swaps. I wouldn't re-oil them for days/weeks while waiting for the filter to dry out from the wash. If that isn't meticulous enough to stop it from happening then I dunno!

 

Have to admit, I havent seen that style before. You would think that the most efficient use of a filter would be to expose the largest surface area to the incoming air. I checked mine ( SLP cold air kit) and the fresh air enters thru a hole in the side of the box and is pulled thru the filter's outside diameter , in to the inner section and up thru the duct to the MAF. So the outside of my filter gets the oil.

 

instead of using this weird inside and outside terminology, lets stick with engine side (filtered air that goes to the engine) and intake side (unfiltered air on its way to the filter)

IMO, unless the filter was wet to the touch and oily and greasy, you shouldnt have a big problem with filter oil...
however, if you have determined that oil is the cause of your problems, i would re-evaluate how you are oiling your filters...