RB25det hesitating under boost, loss of power. Help!

[streeteg]

Heres the low-down.

Stock rb25detFMICgreddy type s bovavc-r boost controller set to 10lbsstock ECUstock MAFstock ignition.

Was driving the other day and the car was cruising just fine... hitting boost like normal, idle like normal, 10lbs all day throughout the RPM band. Felt very solid. Then as I am cruising back to my house and under load, just as the car builds around 6-7 lbs @ 3300 it just stops making power, and hesitates very noticably. At the time I just chalked it up to heat, but I took it out again today and same thing.... It will cruise out of boost just fine, even build a little under load, but as soon as it feels full boost is going to hit, power just dies off.

My instinct tells me MAF, and I havent checked it yet...but if so... I have access to a z32maf...will that work with a stock ECU?

Sparks look good (little dark, but as expected running untuned). Any suggestions? maybe a ground? vacuum line?

First places I should check?

Let me know! Thanks in advance....

-Eric

[Sil240]

I'm having similar type problems.Check your IC piping make sure you dont have a boost leak.

But no you can't just hook up a Z32 maf.It may run, but it'll run crapy.

[radianation]

I've got a similar issue at 5500 RPM but it's because of my wastegate. It can't handle the boost so it craps out. I have a new one ordered.

[mello88]

Sounds like a classic boost leak.. Pressure check your intake pipes, look for a blown off coupler/clamp, etc..

[Shocker]

Sounds like a classic boost leak.. Pressure check your intake pipes, look for a blown off coupler/clamp, etc..

yes sir it does. Couplers are most likely slipping/opening when a bit of boost hits thus killing power, but when out of boost they are still on ok. Check hard!

[streeteg]

ha wow---totally gave myself up as a noob to boost.... coupler under the throttle body was undone--- redid that sucker and its boostin like a gem.

Thanks guys!

-E

[tgxlayzie]

im having a similar problem da car jus hesitates like its chokin or sumtin wen i hit bout 6000rpm can that also b a boost leak

[streeteg]

learn english, then yes. check for a boost leak

[tgxlayzie]

my english is fine lol but thanx

[tgxlayzie]

would a boost leak also cause a rough idle sumtimes at idle my rpms just drop

[TwoKSiR]

Sounds to me like it's classic loading up with fuel. I'm guessing it's a MAF issue for sure.

[Darius]

Not necessarily. Could be the coilpacks showing their age and wear if it is breaking up in the high rpms.