Hello everyone! I'm suspecting my 01 Single Cab 5.3 Silverado is having MAF issues. Here is what is leading me to believe this. I previously replaced all 4 02 sensors on the truck because it was throwing code P1133 Manufacturer control. And after I replaced all 4 and inspected the wiring to make sure that wasn't it, it threw it still. I have researched it could possibly be the MAF and I think it's been showing symptoms of just that. It has been idling rough like in the 500-600 range and takes a bit to accelerate when driving and recently not starting first try. Any feed back confirming this and or offering any other suggestions would be greatly appreciated!




Sorry for the long post in advance.

 

P1133 isn't going to be related to the MAF or shouldn't be anyway. The code stands for insufficient switching on the bank one sensor after closed loop is enabled. It does like a test for 90 seconds and see's how many times it switches between that time and sets a code if under the wanted amount.

It seems to be somewhat common with header installs because the o2 sensors are moved from the factory locations and large diameter pipes.

You can always try cleaning the MAF sensor and wouldn't hurt to check for fuel pressure regulator because that can cause hard starts. Prime the fuel system and pull the vacuum line off the FPR, see if it's wet or leaking.

 

Try pouring TWO cans of Techron in the fuel tank, and replace the metal inline fuel filter inside frame rail on passenger side.
. Problem MIGHT go away, if not, you needed a new filter anyway.

 

Thanks for the replies! I will look for any fuel related problems. Didn't really think of that. Fuel filter replacement and maf cleaning or replacement are up next. Hope this solves it.

 

also to go along with with what FFDP said with the FPR, if that vacuum line is wet, whether or not thats the culprit of your issue you should still replace it. its about 60 bucks, and takes less than 5 minutes to do. walmart sells a 2-part MAF/TB cleaning kit made by CRC thats like 7 bucks. I use it every 10k miles or so and can tell a difference with throttle response. if you do clean ur MAF make sure that you let it completely dry (do not use compressed air to dry it!! you'll **** it up) before reinstalling

 

Really? I was a bit skeptical with those Maf/TB cleaning kits, but if you've had good results and the price is low like that I might as well take care of that as well this weekend! I'll also be replacing the fuel filter for another cheap and routine maintenance solution. I did notice this weekend, while changing out my spark plugs and wires, that the stock intake tube is a bit crunched as in it's not straight heading into the intake box. I'm sure that may be a problem but not sure if that would throw that engine code or not.

 

ya i think its one of those things that the people that dont like them didnt do it right, i.e. dowse the MAF with the cleaner, immediately put it back on soaking wet, then go driving. as long as you follow the directions and let the thing completely dry out then it should be ok. and really, with a 7 dollar price tag you could do it every oil change.

what do you mean the intake tube is crunched? like, does it look like something crushed it, or naturally that way from the factory?

 

Agrees definitely sounds to be a win win situation doing the cleaner if done correctly lol!

And I've noticed it's not a normal crunch. Looks to may actually be causing a restriction in air flow. I tried to straighten it out but will most likely get a cold air here soon. But would this cause any check engine light to come on?

 

For code P1133??

 

u able to post a pic of the tube u are talking about?