wot bog half throttle pulls hard

[zachwilliams02]

Ok so like the title says. I just bought a talon tsi and it has a 16g and wideband. Other supporting mods like a fmic and exhaust. Well long story short. In all the gears it seems like I'm hitting almost a fuel cut at around 5k Rpms. It will pull till then then its just like the power drops off. Now the fuel pump isn't rewired yet but when I'm at wot it is almost a 10/1 afr but at idle it is 14.7 I'm only running 15psi on stock internals and injectors. I can't find any boost leaks. So idk what the problem is because if the fuel pump was the problem wouldn't my wideband show that it is running lean? Any help is appreciated

 

[Diamond Star Werks]

I hit fuel cut at 15-16 psi with a 14b. Your most likely cutting too.

 

[zachwilliams02]

Idk why tho because my wideband says that it is pig rich not lean. I don't have any logger or anything like that. I'm not super sure about any boost leaks but I just sprayed carb cleaner around all of the couplers and intake mani and the revs didn't rise. I wonder if the stock bov is leaking. The guy replaced every piece of ic piping with hsrdpiping except for the one behing the fuse box probabily because it would make it so the box was un bolted

 

[jed344]

I don't think your wide band has to go lean for it to hit fuel cut. But i would guess its fuel cut my friends car hit fuel cut at 16psi with a 16g. I also hit fuel cut at 17psi on a 14b. We both went ecm link and have never looked back.

 

[Diamond Star Werks]

Just because it runs rich doesn't man you won't get fuel cut. Its determined by an airflow rate or specific mass air flow and injector duty cycle. Not by air fuel ratio. it will always read rich as your stock target a/f ratio at high load/WOT is 9.6:1

 

[c2ypt1c]

Fuel cut is not caused by lack of fuel, it occurs when the ECU sees too much air (high maf signal). If it was fuel cut, I'd expect the wideband to read lean when it occurs.
EDIT: ^ MJ beat me to it

Try lowering the boost to wastegate pressure (10psi or so). If it still bogs, i'd say it's ignition (plugs, wires, coils) or fuel (pump, filter, injector, 87octane) related.

 

[zachwilliams02]

I just put new plugs and wires. the old wires were so trashed he had electrical tape holding one together. I'm going to rewire the fuel pump tomorrow and I have 2 extra set of injectors that ill try swapping into it. If that doesn't work ill lower the boost. Iremember i ran my 14b at 18psi and it pulled great except for high elms. But that's because it was too small haha

 

[Diamond Star Werks]

I just put new plugs and wires. the old wires were so trashed he had electrical tape holding one together. I'm going to rewire the fuel pump tomorrow and I have 2 extra set of injectors that ill try swapping into it. If that doesn't work ill lower the boost. Iremember i ran my 14b at 18psi and it pulled great except for high elms. But that's because it was too small haha

You need to remember boost is just back pressure. Your forcing air into the engine and it can only breath so much. The healthier it can breath (bigger cams, exhaust,valves, port work) the more air you can get in and out. Which means you can flow more air at lower pressure.

Take a stock 2g, install a 14b, you can probably get 18psi before fuel cut. Then install a 3" catless exhaust, some 272s, evo3 16g turbine housing and o2 housing. Now you well most likely only be able to run 14-15psi. Your not making less power but more per psi because your engine is breathing that much better. So your flowing the same amount of air at lower pressure.

 

[zachwilliams02]

ok well i just turned the boost from 15 to 13 with no differemce stiill going to re wire it and see what tht does. just seems odd to run such a low boost. im used to runing 18. not 13. my onld ones definately had more power than this one. ill just fiddle around with it. next upgrade. i hope my parents are buying me dsmlink for my grad gift.

Hey guys I think I figured out what the problem is. i dont think it is fuel cut. Upon looking around the engine bay I noticed it has tic injectors..... Well imvrunning a stock tune so that would cause it to run rich on wot. I have 2 sets of the stock 450 at my house so ill keep you posted

 

[T is for TURBO]

If you're injectors are larger than 450cc, and no way to control them, than that's likely the issue.

I just sprayed carb cleaner around all of the couplers and intake mani and the revs didn't rise.

Just so you are aware, this in not an effective way to look for boost leaks. The engine doesn't pull enough vacuum find leaks. -18 inHg = -8.8psi.

The only sure way to find boost leaks is to pressurize the intake piping.

 

[zachwilliams02]

Ha ok thanks on the blt I knew it wasn't fool proof but I figured it would show any big ones. I found the other big problem. The two hoses on the boost controller were backwards . So it was causing fuel cut which would then make it only spool to 15psi. I realized this when I decided to try to keep revving it through the cut rt and I saw my boost reach 18 psi thanks for all the help guys

Ok so the boost controller wasn't the problem I got another big suprise. I found out the car has fic injectors. I can't tell what size but I'm pullin them out till I get a safc. I think they may be 750s. They are round with black on the top and grey on the bottom. I can see what I think to be 750 engraved in the bottom of them. What worries me is that I'm not running any tune but when driving around and pulling at half throttle all of the fuel ratios on my wideband are respectable. It's not instill I hit 5k is when my afr really richens out. I caught it at 9.75 the other day