My symptoms before the cure were that if I was in a high gear and a low speed (Say 4th at 30 mph), so cruising at 1500 rpm, and I gave it more than 1/4 throttle, it would buck, fart, sneeze, wheeze..You name it, it made the sound. Heck, it even sounded like it was missing (Or dieseling).

I tried unplugging my MAF, and the problems disappeared. I took the MAF off, and it was filthy! All of the sensors were covered in a good 1/16" layer of gunk. I cleaned them all off with contact cleaner, and though I might as well descreen the MAF while I'm there.

Since I've put the MAF back on, I've had it back up to operating temperatures, and my symptoms are 100% gone.

Maybe we should start an LT1 stumble FAQ, including a check list, including tests that will eliminate the parts of the motor that might have an effect on it. Problem is, there could be so many

 

good fix dude, something so simple, and yet hard to figure out, lot of guys overlook the maf, i know i did, when i was cleaning out the tb i took the maf off to, and was surprized how much crap was in there

 

I also took my buddies MAF off of his car, and it too was pretty filthy. They may not look all that dirty, but once you rub some of the dirty off, the danglies get really shiney.

 

never thought about that one i'll try that one once i get my dam car running again like next week. nice fix!

 

jeez thats alot of junk. I see you have a Moroso CAI could you be oiling the filter to much?

Z~

 

I don't think I'm over oiling it, because I always give the filter a light coat of oil, and then let it sit. All of the excess oil always drips off, leaving (I'd assume) the right amount left on the cotton.

And this gunk wasn't new by anymeans. It was really gunky, caked on carbon. It was just like cleaning a rifle. Who knows where it came from.

 

Well if its dripping off, I think thats to much oil. Think about it the oil stops the dirt right? Now if your oiling the filter to much its gonna suck it straight into the MAF. Just because its not dripping off the filter doesn't mean you don't have to much oil on the filter.

I know this is from an Explorer site but have a look
Over OILING the Filter

Under the hood search

Z~

 

Definetly. Although, as per K&N's instructions, I just spray until it looks like it has the same redness as a new K&N. I then let it sit, and if there's any excess, it drips off.

I definetly over oiled it the first time I put the CAI on, since it was bought used and needed cleaning. This time around, I used it fairly sparingly.

But the carbon on the MAF didn't remind me of filter oil. It's the same kind of gunge that builds up on the throttle body. Maybe it's filter oil that is cooking off on the hot engine parts. Who knows?

 

I fixed my low rpm stumble the same way. I replaced my MAF and the problem went AWAY!!!!!!!!!!!! I agree that the MAF is generally overlooked.


Chris

 

I have the same symptoms, i checked a few things like plugs and wires.. but never found the problem.. Guess I'll check there and hope thats it

 

I just started noticing my very low desiel sounding stumble under eaxy throttle. Then when I go to about half throttle it is fine. I have had burnt wires before but this stumble is different then that stumble was. I have never cleaned my MAF so that is what I will try.
Thanks & I hope it works....

 

holy crap dude! I haven't thought of that!
My car is doing the SAME THING, for a year!! and i still can't get it fixed!
What else could I clean it with, i have heard some people just get like a q-tip and rubbing alcohol or something and just be gentle.. i know that you can break the MAF eaisly but what do I have to be sure Im extra careful with when i clean it!?
Thanks!
I agree that we sould make a FAQ about stubles!! I have tried LOTS of stuff!!!

 

Thats cool, see LT1s have other problems other than the opti.

 

Please post back when you clean your MAF, and let me know how well it worked.

I did it on my friends 96 TA, and it worked wonders.

 

Great post. I never thought about the MAF being dirty either. Maybe going bad or something, but whenever i see these stumble posts, I always think opticrap or coil. Think I look at mine just for the hell of it. Thanks man..