So today I was taking one of my friends out to look at another car he was planning on purchasing for his g/f. On the way we were at a light next to some random amg and he decided to get on it so I quickly followed. Upon accelerating in 2nd gear, about 5k rpm's the car just died almost as if a charge pipe had popped, only after the car dropped to 1200 rpm's and giving it gas it would no longer go. It just sputters around.

No check engine light
No abnormal smoke coming from exhaust
Reset ECU
Checked fuses under hood

All Pipes and sensors seems to be connected properly and snug (Just put the new intercooler and t-bolt clamps on all piping this past weekend).
Car idles and starts perfectly
Fuel pump seems to be on and running with ignition on. All injector plugs seem to be ok.
Car revs parked in neutral. Once you try to move the car in any gear it just bogs down if you give it any throttle above 1%. Park, back to perfect idle and revs, move back to sputtering at 5 mph.

Unplugging the Maf sensor plug at the intake allows the car to drive up to about 2200-2500 rpms (how I got it home).

Now my question is what happened, what did I do. What can I do check/try to resolve this issue

In case needed.
Mods: Buschur TBE (installed about 14 days ago, ETS 4" intercooler installed this past weekend, Perrin intake kit installed about a month ago). Car has no mbc or any other modifications as I was getting ready to order my tactrix cable for self tuning.

 

boost leak....do a boost leak test

 

something is leaking!

did you take your bumper off and check all the coupings? maybe you tightened the t-bolt too tight and it cut into the couple?

 

We checked all the hoses/clamps/pipes several times over and couldn't find anything. There is no undertray on the car so we were able to stick our head under the front bumper and few all the intercooler connections, licp, uicp, etc. If it were a boost leak wouldn't the car take gas up until boost and then proceed to fall on it's face? Right now it won't go anywhere above 1000-1200 rpm's, but with the maf sensor unplugged it will go up to about 2000-2400 rpm's.

 

did you check behind the intake manifold to see if any of those small hoses poped off?

do you have a boost gauge? if so whats the vac reading?

 

Due to the lighting we had I couldn't really see under the manifold. Engine was still a bit hot as well. From what we could see it looked ok, but obviously we couldn't see much back there. Have a lift available where the car is at, but unfortunately I've been finagled into working all day tomorrow/night and all day saturday for some server room projects. I won't have a chance to get out and look at the car until saturday night/sunday

 

^^ do you have a boost gauge?

 

The stock boost gauge is in there now and have a prosport sitting in closet

 

Your out of gas!!

No but really, It sounds like something is caught in your Maf. Check it out

 

Check the BOV.

I've had a similar experience... I had just put the upper pipes back together, and took the car out for a test spin. Heard a hard sputter... and coasted off the side of the road. Turned the car on, it idled just fine... tried to move the car in 1st, and it would almost die. Checked under the hood, and the BOV had popped off the coupling on the intake.

This may be your problem... I know you said you checked all your pipes and connections, but take another look there. Sometimes its difficult to spot; it could be just hanging off - half on/half off.

 

Yeah definately. I appreciate all of the help guys.

Plans for the weekend once APC gets the new UPS poo in and I get servers operational. Should be able to get out of here by 6 on Saturday and get to the piece to do some work.

Take Front bumper off
Take LICP off
Take UCIP off
Take Intake piping off
Inspect the MAF plate and honeycomb filter or w/e it's called
Inspect plugs
Replace plugs/wires (Tune up in process)
Check all vacuum lines
Put all piping back on
Boost leak Check
Replace fuel pump (walboro in closet)
If same problems and no leaks/issues found.
Compression test and back to boards

 

Checked the 20 amp fuse in the fusebox for Ecu under hood ?

 

had the same problem it was the bov as well

 

Yeah, we checked the ecu fuse.
Tonight I got a ride over to the car after work from a coworker.
In the pouring rain I put the car in the air and took the LICP and UCIP off. Took the recirculating hose and BOV off, checked the intake pipe on the turbo, inspected all the pipes, hoses, and couplings for cracks, holes, anything that could cause leaks. Did not find anything. Put everything back on and double checked all the clamps and car is still doing same thing. I got tired of swimming in the rain so called it a night. I did inspect all the vacuum lines while I had the pipes out, but did not see any problems.
I won't get a chance to get back out there until late Saturday night or Sunday to look at more stuff.

Next things to do are pulled the intake and maf out and inspect thoses, pull and plugs and check and then run a boost leak test.

Had my friend's grandfather do a ride along tonight. He's in his 60's and still racing and has been working on cars his whole lifes. We both agree that it doesn't seem like a boost leak, vacuum, or piping issue. It almost seems like an ignition issue or something with the ecu. It feels like the ecu is in limp mode or something and the fuel cut off is set to 1200 rpm's. It seems like a really weird issue. If we can't get it resolved by the end of the weekend, I'll probably have to tow it to a shop to take a look at.

 

boost leak test my friend... have a water bottle to spray