Boost issue (hitting brick wall)

[Everthrill]

So I'm looking to buy a clean DSM Eclipse 106k miles rust free. When I test drove it it ran and drove fine out of boost (0-3k rpm) sounded healthy idled good no excessive smoke or check engine lights or anything. But the moment I went to build boost it would start to build and even gave me a few good pulls but then it started to cut hard. It's hard to explain but it felt like it was about to go crazy then hit a brick wall with 0 acceleration.

The boost gauge (stock one) would hit in the middle of the gauge then all of a sudden go back to 0 once it cuts. I have nothing as far as charts or anything as I don't own it.

Any ideas would help greatly as I'm a naturally aspirated person not into turbos but want to learn

 

[luv2rallye]

First EASY check is to make sure all the intake air hose clamps are tight and not missing (from air box to turbo, turbo to intercooler, intercooler to throttle body). Any leaks can cause that. Second would be if the blow off valve is bad (not holding pressure - opening too soon).

 

[Everthrill]

First EASY check is to make sure all the intake air hose clamps are tight and not missing (from air box to turbo, turbo to intercooler, intercooler to throttle body). Any leaks can cause that. Second would be if the blow off valve is bad (not holding pressure - opening too soon).

So the issue changed a bit it was running poorly only around 3kish but not it runs poorly at all rpm till like 6k. The plugs were very Rich and compression is good. Air to fuel is very wrong its flooding itself basically and the only engine code I'm getting is miss fires I drove it to work and back today and it struggles to move once it gets going it clears up the higher the rpm. If I try and push it past quarter throttle it'll miss bad again. Really wierd cause all timing and compression is good now it's up to vaccum and turbo. It has an exhaust leak somewhere near the front and under my driver seat so I'm going to see if they are pre o2 or not.

 

[pauleyman]

Please fill out a profile. You haven't even told us what year car it is yet. We need to know all the details of what the car is about.

 

[motomattx]

I would recommend that you not push it, it could be detecting knock and pulling timing to try and protect the engine from damage.

 

[pauleyman]

So I'm looking to buy a clean DSM Eclipse 106k miles rust free. When I test drove it it ran and drove fine out of boost (0-3k rpm) sounded healthy idled good no excessive smoke or check engine lights or anything. But the moment I went to build boost it would start to build and even gave me a few good pulls but then it started to cut hard. It's hard to explain but it felt like it was about to go crazy then hit a brick wall with 0 acceleration.

The boost gauge (stock one) would hit in the middle of the gauge then all of a sudden go back to 0 once it cuts. I have nothing as far as charts or anything as I don't own it.

Stock boost gauge at zero is indicative of no airflow assuming the car has no other issues. If the car has an aftermarket boost gauge how does it compare?

Any ideas would help greatly as I'm a naturally aspirated person not into turbos but want to learn

Give us info. Fill out a profile. What car is it. What's been done to it etc.

 

[Wizeman76]

Fuel cut would be my first thought, too much boost.

 

[Kryndon]

Building boost then hitting a brick wall is a dead giveaway for fuel cut. MAF is sensing more airflow per given engine load than it has fuel mapped for it, so it activates the failsafe which is to cut all fuel delivery. Things to check would be MAF (connector, sensor, wires), check if you in fact have the stock T25 turbo (if 2G) or TD04-14b (if 1G), you can take a picture of it and attach it here so we can tell you. Also, pull the ecu and inspect it; check if it is the right part number for your generation car, and open it up to check if it has been tampered with (chipped, damaged, piggybacked etc.).

The more details you can give us, the more accurate we can be with troubleshooting.