Jump to content
SAU Community

4g63t not making boost?


Caleb_M35
 Share

Recommended Posts

Hi all, new to the 4g63t world and I figured this would be the go-to section to ask questions. I am purchasing a vehicle running a 4g63t from an Evo 3. Apparently it was running wonderfully although untuned until parked up 2 years ago. It had been started regularly but not driven on the road. The motor and turbo (eBay spec GT3582 A/R .70 'Anti Surge' turbo) look, sound and seem generally healthy. The problem is that the car now makes no boost. The turbo spins and spools happily with no shaft play or funky noises,  the motor revs happily but no boost gets to the motor. My thoughts are that there is an issue with the external wastegate or actuator, BOV or a serious boost leak. Would I be correct in assuming so? 

Link to comment
Share on other sites

On 5/29/2018 at 8:52 PM, KiwiRS4T said:

You are testing it while driving, not revving it in neutral?

Correct, test drove up to 100km/h and through all 5 gears

Link to comment
Share on other sites

You really need to do a boost leak test to see if a silicon hose is split, or if the intercooler etc has damage such as a crack. Even with a significant boost leak you will see some positive pressure (boost) reaching the engine and you will usually hear the gush of the escaping boost unless your exhaust is very loud. 

You also need to check to see if the wastegate or bov are seized in the open position, or if some foreign object is stuck on the seat of either of these and bleeding boost.

Check for back pressure in the exhaust. Something may be obstructing the flow.

Good luck

Link to comment
Share on other sites

On 6/1/2018 at 12:01 PM, 360CF said:

You really need to do a boost leak test to see if a silicon hose is split, or if the intercooler etc has damage such as a crack. Even with a significant boost leak you will see some positive pressure (boost) reaching the engine and you will usually hear the gush of the escaping boost unless your exhaust is very loud. 

You also need to check to see if the wastegate or bov are seized in the open position, or if some foreign object is stuck on the seat of either of these and bleeding boost.

Check for back pressure in the exhaust. Something may be obstructing the flow.

Good luck

Thank you, all the above have been thoughts and this has confirmed my suspicions on where to start. The exhaust currently dumps at the firewall so there is zero obstruction. The previous owner only had an eBay wastegate on so that will be the first thing to come off and be replaced. 

Cheers

Link to comment
Share on other sites

Found the issue! It turns out the guy before me didn't install the metal o-ring that seals the wastegate valve. New Turbosmart gate on the way...

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share



×
×
  • Create New...