My Car:
1999 Mitsubishi Eclipse Gs
(Aftermarket JDM t4 turbo)
Jdm bov and intercooler
Precision turbo wastegate
and aftermarket exhaust

My Problem:
Ever since I have owned my car the CEL has been on throwing a code for a p0401, which I cannot seem to figure out because the egr valve seemed fine when I took it out to clean it and look at it. I have also noticed a severe decrease in gas mileage, and it slanted from around 24-26 to 18 which is almost as bad as the awd models. My atf gauge reads rich now and it never used to be that way and I am wondering if the egr valve would be the only issue becuase I have limited funds and I can't go buying tons of parts that won't fix the issue. Any insight will be highly appreciated. Thanks

 

I'm guessing you bought the car already modified?

Is the car a GS 420a, or a GST 4G63?

 

Yeah bought it modded running a 420a

 

We can sit here all day and dick around with this, and never come near the problem. When people hack these cars up and slap cheap ****ty eBay 'JDM' parts on (there's no such thing as ANYTHING JDM for the Eclipse, since the car was made in the United States only) them, anything can happen.

Take the car to a shop.

EDIT: That narrowband gauge is garbage, it doesn't mean anything.

 

Well I mean I might have a boost leak in my intercooler and I am replacing it soon but would that throw a p0401 code for egr exhaust circulation?

 

Why are you going to replace random parts? You're just going to waste money.

 

Well I need to my fmic is sagging in the middle and it looks like a U now instead of a rectangle haha

 

That's because ****ty parts were used making it.

Sell that car, it sounds like a basket case.

 

Not going to disagree there the car definitely needs quality parts but I want to fix that stupid cel before I go any further and it randomly comes on and off when I am driving for minutes at a time

 

You'll spend more than the cars value putting it right.