Blew my MAF apart-unglued

[Martin U]

What might cause a MAF to split in 2 pieces. I had just installed a boost controller and made a run earlier in the day. 20# boost-Ok just where it was, no problem. I went home and checked out my PL files, just a hint of KR 1.0-1.2.
Mind you I'm just learning to tune with this WB.
I felt i was safe giving the mbc 2 turns to see if it changed my boost pressure. added more alky just in case
I was rolling in to it at about 50mph. Boost came up-BANG. "DRT" It spit and sputtered home. I took a look on the side of the road under the hood and it split apart from the maf pipe on the TB side. meaning it was getting lots of air AFTER the MAF.
Was able to hold the 2close enough to get it to run-sputtered a bit at tip in is all. When i got it in the garage, I removed the MaF and found it had split along it's long axis. It looks like it was glued that way from factor. Some of the hot glue?? inside the circuit board area had turned soft and jelly like.
I'm thinking I could just epoxy it back together. The hard part will be the round piece thatwas still in the pipe.

It spiked my KR & jumped to 30# of boost.
Question is 1) what would cause this,how much pressure does this thing see at times?
2) can I epoxy/jb weld it back together with some band clamps?
I'm sure the MAF went first then all the readings went haywire.
I'm an unemployed diemaker CNC programmer in mi,so all the fancy$$ parts will until i can learn to make pizzas or something.
It seemd to run smoothe when I held the pipes together,making me think if I did a good fix it should be OK for a short time.
What cha think?
Mart Urbanski

 

[justin84]

Just moved from Flint (also an unemployed diemaker) Chances are it may have been dropped at one time. These things are fragile.

 

[Razor]

Your not using a plastic MAF on the pressure side of the turbo are you?

 

[TrAb]

Yeah that sounds weird like its under pressure

 

[Grumpy]

I have a reman sensor that did that.. POS.. yours a stocker ??

 

[Martin U]

I was given this sensor by tom? a few years ago. he said i couldn't run a 84 maf with a 87 ecm. I believe he said it was org. Ran fine for a couple of years.
stock HOT-AIR setup.
It is a plastic body. I just looked on one half of it near the plug. It has a reman sticker on it.
I will post a pic when I get back from my errands (house B***h)

 

[mikestertwo]

Your not using a plastic MAF on the pressure side of the turbo are you?

+1

 

[Martin U]

Nope! Air filter>maf>inlet tube>throttle body>turbo>round and round>out the other end.
HOT-AIR no intercooler. I asked in the tech forum because it was a 87 MAF & 87 ECM. I didn't know if this would matter much because of these specific pieces..

Mart

 

[Martin U]

Here is a shot of the MAF.

 

[ijames]

The backfire is what split the maf, it normally only sees atmospheric pressure. You had a little knock already, and then turned the boost up. You mentioned a wb, what was the afr before you turned the boost up, and right before the backfire? Sounds like it went lean, knocked even more, and backfired.

 

[bmackinnon]

the backfire is what split the maf, it normally only sees atmospheric pressure. You had a little knock already, and then turned the boost up. You mentioned a wb, what was the afr before you turned the boost up, and right before the backfire? Sounds like it went lean, knocked even more, and backfired.

+1

 

[Martin U]

I had been turning back the chip,It as getting better. No knock. then I added thr RJC controller and gave it 2 turns, I think it was getting closer to 10.3-10.5 from a very rich condition. At least the motor is ttill together. How much boost increase do you get per turn with this controller/
Where is the best deals on a LS1 maf? 7 translotor?
willing to trade some goodt parts for some of the things i need.
Will bone yards have the new MAF's,How much to expect to pay ?

I was working my way up @20lbs boost and the numbers were moving up as i was told they should be.
I have the PL run If you folks care to look at them.
Mart Urbanski

 

[Razor]

Would appear the air filter would have to be restrictive. I mean its like blowing a straw apart. Hard to do unless there is a restriction on the tip.

Change air filter for sure.

 

[DailyDrifter]

I agree with the other guys about the lean misfire. I would be glad if the MAF was the only thing that let loose. Who knows if the important parts of the MAF are good anymore. I would get a new one, but if the MAF still works when you put it back together, who really cares as long as it works . I would still be getting a new one though :wink:

 

[Martin U]

?? I don't know, air filter looks good. It seems to me some how the air got backed up,and tried to stutter like a 87, then it blew,OR it was so old that it just let go,spiking every thing behind it.
I had it off when i added a good intake tube. IF I had it to tight on the clamp behind the electronics, and it cracked,broke that would allow a ton of un-metered air in,it goes lean backfires then takes the whole unit out.
the round seat where the TB pipe was attached was still clamped to the tube, that is where it started is my first guess. I know I have some shorts to wash!!
I'm also pretty happy that my build of this motor is holding up-it's all the ather pieces around it can't handle it.

Here is a log file of a couple of runs

 

[DailyDrifter]

I don't know if your 39lb injectors are going to be able to handle a 30 psi spike at WOT , did they max out?. How old is your fuel pump, filter, injectors, and regulator? Any fuel psi readings? She obviously went lean, to say the least . What was your o2's doing (FWIW, I can't see any of your data logs)? How much alky are you spraying?

Also if you get a new boost controller, just roll into it a couple of times, 2 turns can be alot sometimes. I had a turbonetics MBC with a fresh rebuild and combo and it spiked my 30lb boost gauge on one of my first test runs with ease (TE45a,72lb'ers,no alky), and yeah..... she popped a little , what a great way to start things off

 

[Martin U]

Well i don't think the 30# was intentional, that happened AFTER the MAF blew.

Alky at about 7,pure meth.
new fuel filter
pump about 3yry old hot wire ect
accufab FPR

see if you can read these , I didn't zip them
one run is climbing up on the tune
one is where the maf blew see if you can spot which is which:wink:
At 22.5 lbs boost---WB=10.83
MAF=256
KR=1.8
Alky 6-7
duty cycle=72.3
spark adv. 19.1
It will not let me load an unzipped file & I don't know hot to get a screen dump.

No water in oil, no bubbles in rad, It ran with the maf taped together.
I built this engine strong in case things like this happened.
Now to decide on which way to go on fixing it.,ls1+translator. Or can i find a good maf??any ideas/ I see some venders selling remans are they any good?
Thanks for all your input every one,this will not stop here.

 

[DailyDrifter]

What was the TPS voltage at WOT? Any exhaust leaks? I would get a Turbotweak chip, and maybe even look into speed density system and ditch the MAF

 

[BRAD_PADGETT]

Now to decide on which way to go on fixing it.,ls1+translator. Or can i find a good maf??any ideas/ I see some venders selling remans are they any good?
Thanks for all your input every one,this will not stop here.[/QUOTE]

IMO the reman. MAF route is a big mistake. The LT1 MAF work just fine and are very plentiful at the boneyard or buy new. The MAF translator will be needed. The speed density chip does work as well if you are inclined to program the chip. Good luck. Brad

 

[Martin U]

Hey Brad,
I'd love to have that SD chip,but that also means injectors to. So until i get a job.Diemaking used to be the cream of the crop here in Michigan,now NAFTA. Those things will have to wait.

Any specific cars,engines that run these mafs, so I know what to look/ask for in the boneyards/
Thanks
Mart