detonation or fuel cut?

[JParrish]

Hey guys, I have a problem I can't solve. I have searched every forum on this site and can't find my exact problem. If you read my stats you know I have the fake evo 16g, maft and 3" gm maf. When the car is at 3500 rpm and above with 15-18 pounds of boost the car begins to have what I call fuel cut. I am running 93 octane fuel. I have checked fuel psi at the time it does this and its a steady 34psi, I have done a boost leak test to 25 psi and it heald. I have the maft mid and wot switches set as rich as they will go and the injector size set at 430cc. I still have the stock 450cc injectors. I do not have a data logger nor the money to buy oneat this time. If some lives in south central Indiana and would be willing to help me pm me please. Sorry for the long message but I am really about to pull my hair out with this one. Thanks guys and gals.

 

[slow4g6392tsi]

Get some bigger injectors.

 

[BoostFrenzy]

You need a whole fuel setup (Both flow and control). In the mean time, turn down the boost to keep it from blowing up.

 

[JayRolla]

What is what you call fuel cut. How can we help you if you say whats wrong is what "YOU" call fuel cut. What is actually happening and how much boost you pushing?

 

[jrohner]

Hey guys, I have a problem I can't solve. I have searched every forum on this site and can't find my exact problem. If you read my stats you know I have the fake evo 16g, maft and 3" gm maf. When the car is at 3500 rpm and above with 15-18 pounds of boost the car begins to have what I call fuel cut. I am running 93 octane fuel. I have checked fuel psi at the time it does this and its a steady 34psi, I have done a boost leak test to 25 psi and it heald. I have the maft mid and wot switches set as rich as they will go and the injector size set at 430cc. I still have the stock 450cc injectors. I do not have a data logger nor the money to buy oneat this time. If some lives in south central Indiana and would be willing to help me pm me please. Sorry for the long message but I am really about to pull my hair out with this one. Thanks guys and gals.

You say you have it set as rich as possible - that's why it's fuel cutting. Fuel cut is based on airflow, richer on MAFT's or AFC's means higher airflow shown to the ecu. Stock, these cars are tuned super rich the way it is.

15-18psi? I would be amazed if you could run 18psi on stock injectors without leaning it out a bunch. 15psi is probably max.

You need to find someone with a logger so you can adjust your MAFT. You can probably go quite a bit leaner but may need to back off your base timing a couple degrees.

Leave the car at about 13-14psi until you can log it. Start saving for a logger and some injectors.

 

[williampaul]

I have a prime reason why NOT TO RUN 18 PSI ON A STOCK FUEL SYSTEM...
92 laser awd 6bolt 4bolt combo. picked it up for 600 and thought it had a blown head gasket... to my dismay i pulled the head off this past weekend and it had a hole in the #1 piston the size of a my thumb. if you want to keep the internals in your car cut the boost down to 14psi maybe untill you can afford to buy pump and injectors and a fuel computer. dont dick yourself just trying to go fast without the supporting upgrades!!!

 

[JParrish]

Thanks guys for the replys. I have no boost controler. 15 to 18 psi is with the wastegate actuator that came with the turbo. I did adjust the wastegate arm as posted on this site and tested it, didn't help. I have an actuator from a td04, will that lower the boost pressure or will the turbo over run it? When my buddy had the td04 on his car it only boosted to about 10 psi. If that doesn't lower the boost I will have to install the td04 because I need the car to drive to work.

 

[JayRolla]

Just dont hit the gas and you wont be in boost, .

Anyways fuel cut is a brick wall, is that what you get?

 

[bmoha2]

Fuel pump rewire, adjustable fuel pressure regulator, upgraded fuel pump, larger fuel injectors (550s minimum). And also a tuning system.

 

[williampaul]

i will recommend 680 injectors and a neo(great now that they fixed it). thats the setup i have on my gs-t now and it is unbelieveable how hard it pulls. also did a fuel pump rewire. that itself allows for i would say around 2 extra psi of boost.

 

[bmoha2]

550s minimum but 660s would work a lot better and do the fuel pump rewire. It definitively helps even though some scoff at it. It's a little extra insurance and is very easy to do and inexpensive.

 

[JParrish]

I appreciate the upgrade tips but I know what the upgrade paths are and I intend to do all the fuel upgrades as soon as christmas and all that other holiday stuff is over. I need to know how to lower the peak boost so the car is drivable. I have 2 kids that come before the car so I need to go as inexpensive as possible right now. I have found a data logger cable for my laptop and I am going to download one of the free program so I will atleast be able to see whats goin on . Do I need to install the complete td04 turbo or can i just install the wastegate actuator from the td04 onto my td05h to lower the peak boost? Thanks everybody.