So I bought my Evo back in 2005 all brand new - nice and shiny.

Did the responsible thing and since it was a daily driver didn't mod it too much for the first 7 years of its life. Just did a catback exhaust, intake, tune.

Since it's been paid off a while and I got a new daily driver, I decided it's time to finally have some fun with the car.

At 102k miles I installed a set of BC 272 cams (still stock springs & valves), and added a downpipe and high-flow cat.

Just got the car back on Friday, and it hadn't been tuned yet, so I was going pretty easy on it, but still getting into boost. Didn't look like it was running lean, and was around the 11 mark when it did go into boost.

Switching highways on the on-ramp, went through 3rd gear with some moderate boost just fine (and this is after 35 minutes of driving already), and then switched to 4th gear. As soon as I get back on the throtle and the turbo starts spooling again I hear a nice "boom" sound , and the car kind of feels like what happens when you have a spark plug not gapped quite right..like it's not firing.

No check engine light comes on, and the car is still running, but when I press on the gas, nothing happens...it just keeps on winding down in RPMs. No smoke, no rattles...sounds like a normal engine winding down.

When I get to the side of the road and press the clutch in, the car stalls and won't restart.

No leaks - nothing.

Any ideas on just what I broke here?? Scared to death it's the motor, but it was still running after this, and no smoke or fluid leaks, plus looks like it was running in boost just fine?

 

double and triple check your intercooler pipes? they might look to be tight but I had an issue with them popping off all the time and it would do what you described. good luck

 

Sounds like one of your ic pipes might have come loose.... Have you checked all of your ic plumbing to make sure they are nice and tight....

Go through your engine bay and make sure everything is plugged in .... no loose lines etc....

That's my initial guess....

I'm sure someone else will have a better suggestion for you to consider.

GL!

 

Yep, sounds like you popped an IC coupler. The "boom" sound is the pipe or coupler popping off.

 

Thanks for the quick replies!!

Everything looked OK with the intercooler piping believe it or not....

Any other ideas?

 

Ya, do a boost leak test.

 

Looks can be deceiving for a boost leak!

 

check the lower ic pipe where it connects to the ic , mine looked ok and untill i removed my bumber i noticed it wasnt all the way in from the top ... good luck fixing it

 

Double check...pipes. by throttle body. best is the boost leak pressure test.

also try and start it with MAF disconnected. if its an IC pipe usually the car will stay running with the MAF disconnected.

 

Ha same exact thing happened to me. Check the first time, and couldn't see the coupler that came off. Freaked completly out thinking I blew my motor.

Finally got the car up on the drivers side, and it was my lower IC pipe.

GL bud!

 

Yeah, you need to physically check the IC piping, as stated looks can be deceiving.

Also of note is the pipe at the throttle body, it tends to balloon under boost and force itself off.

 

As your looking at the car from the front it's usually the First left one that comes off the intercooler

 

Maybe the pipe under the maf I had that blow off before and car didn't run if u hit the gas

 

Turned out to be a crank sensor....anyone else had this problem?

 

You mean the code you got?

The ECU throws that code any time the car falls below sustainable idle and dies. I'm sure your sensor is fine, especially considering there's no way for it to make a "bang" noise. You NEED to check all of your IC piping like everyone here is telling you.