Mark Bradley

Hi guys,

A couple of months ago I deleted a few things including the double throttle with the butterfly valves and ACV with air pump etc. It is also a JDM model so there is no EGR or AWS to begin with. I decided to leave the idle speed control installed.

When putting it back together I accidently got a couple of vacuum lines mixed up including the one that goes into the MAF. Long story short I drove the car about half a mile down the road before there was a huge bang and a large bloom of black smoke coming out the exhaust. Thankfully, the engine seems fine, and I think it was old build up in the original cat getting released. I quickly fixed the issue, and the car drives fine again.

However, it is now drinking fuel at a much higher rate, and it stinks of fuel coming from the exhaust. I was originally getting around 18mpg which has since dropped to around 12mpg. I also have an idle issue after the engine gets up to temp. I think it might be back pressure in the exhaust throwing off the 02 sensor but when I have inspected the Cat it seems fine with no damage from what I can see. Before I go ahead and get a high flow cat I am wondering if anybody else has experienced this? I have the PFC which I have reset several times hoping to solve the fuelling issue but no luck. I also have deleted the OMP and I now premix which I did at the same time as the delete. I also replaced the 02 sensor and checked the injectors and fuel lines for leaks, and all seemed fine. It also has a fresh set of new plugs and a tonne of major boost leaks fixed at the same time hence why I am struggling to identify the change that has caused the issue.

Any insight would be appreciated.

Cheers.

gracer7-rx7

iTrader: (16)

Doesn't sound related to the cat.
I'd check your fuel injectors. Almost sounds like one of them is leaking during combustion. Maybe try a fuel pressure test to engage the fuel pump and look / listen for leaks.

Mark Bradley

Thanks gracer. I'll have an investigate and post an update. 👍

Mark Bradley

On the money. One of the secondary injectors is sticking open. I could hear a small hiss noise when presing my ear to the manifold with the ignition on. I gave it a small crank without starting it and one of the injectors continued to dump fuel for a good 15 seconds before returning to the hiss sound. Probably explains why it started first crank when I put new plugs in then went back to needing 4 or 5 after. Probably soaked with fuel.

Thanks again.