I recently installed a mr manifold and o2 housing, I know the mr is a ****ty manifold, but I just stuck it on while I'm sending my cast mani to get ported and coated. Anyway ever since I've installed it, I've been having problems with the power cutting out. The car drives fine down low, but when I get up around like 6500-6800 rpms I hear a loud noise and the power shuts off for a few seconds, then when I shift to 3rd, everythings fine again. The check engine light came on the last time it happend. Anybody have a clue what this might be??

 

describe the loud noise

 

Well it's not so much a loud noise, kind of a thud, it doesn't sound like like a pressure release. Imagine launching, but just dropping the clutch, it's the same kind of feeling, like you can feel the engine torque back from the power just leaving all at once. I've checked all the lines, nothings leaking, boost is still holding like normal.

 

you need to pull the code and see what gave you the cel

 

you just hit fuel cut

 

Ok so I've made about 5 trips to Autozoze to figure out whats throwing the cel, and the only thing I can figure is that Autozone has started a "speacial people" program like Mcd's... because everyone there is a complete moron, apparently they only have one employee that can run the diagnostic, and nobody knows when he's working again. Why would I be hitting the fuel cut though? my only other mod is a tbe.

 

Yeah, Fuel Cut.

What are your other mods? It's probably a combination of things that the new Ex Man and 02 may have brought on. You are likely flowing more, which means the ECU is seeing more air / boost.

This happend to me when I replaced the stock diverter valve. The tuner that I was using back then had kicked up the boost to 24 with the leaky DV on the car, when I replaced it, I began hitting 28+ under load. Not even reving it, just accelerating at a moderate level in 4th.

You might turn the boost down till you get things back, and then get things dialed in again.

 

I don't even have a mbc on yet, I have one, I just wanted to get this problem figured out before I put it on. Do you think a flash would take care of it?

 

One of the Cardinal Rules that DynoFlash states, is don't bring him a sick car to flash

(not meaning that he and others don't fix cars and them flash them - he is talking about things that slow down tuning events),

... so if you haven't had a flash yet (ie, raised boost level), and don't have a MBC, then I would also assume that you could have gotten away with your current installs till the good stuff was put in. I'm going to look at your posts and mods to see if I missed something.

I have run 272/264's, TB Ex with High Flow. 10.5 HS, 22 psi boost (pill removed -but with ball and spring boost controller) on stock maps at 5800+ altitude with out FC,

Not the best approach I agree, but I was waiting to install a Tuner, a Wide band and EGT unit) although without getting into the details, I did have to cut things back a little, still it was manageable.

 

Ok so when I got home from work today I figured i'd try autozone one more time, so start out my driveway and I notice the cel is gone. I really didn't want to throw the cel again cuz it took hitting the cut like 4 times to get it to come on, lol and it's kinda painful, felt like I was hurting my baby. So I just went back to the garage and installed my mbc and it fixed it. I just didn't expect that installing a tbe, header and o2 would be enough to hit the fuel cut. Oh well I'm happy now, thanks for the input though.