Hey guys I was driving this morning and noticed car was idling between "15-17" Afr and sometimes just "---" on aem eugo. Made a wot pull and it was 11.5 or so but after 4.5-5 k it shot up lean so I let out. I'm thinking pump is weak? It's making 415awhp on wal to 255 e85. Car has ran great to this point and boost is 30 psi peak as usual.

 

It just did It all at once so I don't think it's injectors stopped up or anything. No cel, and the car just falls on face like a switch

 

Check the vacuum line going to the fuel pressure regulator

 

Okay I won't be to car till five but I've actually been thinking about that very line in class haha would it make it lean?

 

Clogged injector similar to this?

https://www.evolutionm.net/forums/ev...een-found.html

 

Nice point. I will check injectors and regulator hose both. If not I am gonna lean towards pump

 

check fuel system..its not fuel related check tps same thing happened to me.

 

Hmm I guess if fuel is good I could log the tps and see what it does thanks man

 

OP, this is off subject but do you mind sharing your mod list with me? I'm in the same HP are as you, and just comparing the mods to see how reliable mine could be depending on my parts. Sounds like you've done things right. Want to follow lol

 

Jordan if that fuel pressure regulator hose comes off or splits that would do it like someone else mentioned. Also if you have a boost gauge "t"' into that check that entire line as well. I had a customer that put a "t" in there and the leak was under his dash where a splice came loose. We found it during a boost leak test when someone sat inside the car to watch the boost gauge and it wasn't moving.

 

Evojr they are all in my sig.

Chris thanks for the info I am gonna check this afternoon on the hose to the regulator as well as check the injector tips. If that boost hose came off wouldn't it go rich instead of lean?

 

The gauge still shows 30psi like normal which made me think there wasn't a book leak butttt i will check anyways. Thanks!

 

our cars use a 1:1 rising rate for boost:fuel. That means for every psi of boost you create, the fuel pressure also needs to go up one psi. If the intake hose comes off of the fuel pressure regulator it doesn't raise the fuel pressure up and keep the 1:1 ratio. So you wind up with 30psi of air (because the turbo can keep up with a leak) but the fuel pressure it too low and thus a lean condition begins

It's not uncommon for a car that was tuned to 11.5 AFR to see 13.5 or higher when this happens. That is why our shop makes a point to zip tie that hose on every car before tuning, it's critical.

 

The fpr was the culprit. It is in fact the only hose not zip tied either that or it came off as threw the tie off. Normally I would try to figure out first then post here but I was in parking lot before class when it happened and I just sat in class worried haha thanks for the help guys.

 

When something like this happen especially with evos its always the fuel problem that screw it up lol..Glad u got the problem fixed!