nasty98z28

2001 Camaro
408'' LQ9
F1C Procharger 4.13 pulley
Walbro 450 and 255 (Both are less than 1 month old)
-8 Feed, -6 Return that drops down to the factory line 2 feet after the regulator
A1000 1:1 referenced
SD 3 bar

My problem is, after installing the 255, I left my shop and made a pull, the car blew the midpipe off. After reinstalling the midpipe I drove the car back. After this, I started having a rich issue. Pig rich at idle, it will make your eyes water, longterm trims jumping into the 20s etc.

-I have already smoke tested the car for hours looking for vac leaks.
- New plugs
-New upstream 02s
-map sensor is good and tight in manifold

I damn near don't know what else to look for or do. I have logs from before the issue and after the issue.


The first log attached is before the problem, 2nd log shows the problem occurring.

tim wellington

check or change map sensor,if back fired any when mid pipe blew off .bad map will run rich ,,,been there

kingtal0n

iTrader: (1)

What is with all the fuel pumps? I assume that with $1000 in a fuel system you must have $10k+ in the engine and so obviously you own a $97 fuel pressure gauge and have verified that the pressure at the rail is not overpowering the regulator (What with 3 fuel pumps). I also assume you arn't just blowing the cash without doing any research and are running only a single pump at a time, and adding more as boost comes in (boost activated fuel system). Next, Ill assume since you have 160lb injectors you also have a stand-alone, which means you can adjust how rich and lean you want the engine manually... thus begging the question of posting here online... ? If its runnin' rich you inspect the laptop screen for clues, and then tune the engine how you want it. Next...

forcd ind

iTrader: (7)

Prob need more answers to some questions, lol
Not sure what your calling mid pipe, but a map sensor will throw off the fuel table, I went thru that with my Holley HP, fouled plugs, but I used the CL comp. to save the next set. You don't have a very big return, so the pumps could have overloaded the reg, but I guess you mont. the fuel pres.
You may need a retune-how does the map sensor read with ign on, engine off

nasty98z28

[QUOTE=kingtal0n;19396484]What is with all the fuel pumps? I assume that with $1000 in a fuel system you must have $10k+ in the engine and so obviously you own a $97 fuel pressure gauge and have verified that the pressure at the rail is not overpowering the regulator (What with 3 fuel pumps). I also assume you arn't just blowing the cash without doing any research and are running only a single pump at a time, and adding more as boost comes in (boost activated fuel system). Next, Ill assume since you have 160lb injectors you also have a stand-alone, which means you can adjust how rich and lean you want the engine manually... thus begging the question of posting here online... ? If its runnin' rich you inspect the laptop screen for clues, and then tune the engine how you want it. Next...[/QUOTE

I'm not sure what you mean by "all the fuel pumps", I have two fuel pumps in the tank, a walbro 450 and a walbro 255. Very common for cars of this caliber to have 2 pumps, the only difference is usually they're two matching pumps. Secondly I never verified pressure at the rail, I verified it at the regulator and it was always within range. I don't know why you would assume I had a stand-alone just because I'm running 160lb injectors, they are high impedance.

nasty98z28

I'm calling my midpipe (x-pipe) the exhaust that attaches at the headers, it attaches to the collectors and runs back to the axle. I will get a map reading with ign on and engine off.

nasty98z28

The map sensor reads 105kpa with the ignition on and the engine off. Both my brand new and my old map sensor read the same.

forcd ind

iTrader: (7)

I cant open the logs, do they show CL comp adding or sub. fuel
My map sensor read 100, 101 at 600' above sea level, so you are close
Sounds like something is telling it to add fuel-strange it changed after the exhaust came off
Did you do any welding on the car, I know with just a couple tack welds on mine, it courp. the tune, I had to load the backup-now I disc all the cables
(Holley HP)
I remember my old 408, had a D1SC, blow thru carb, sucker was bullet proof
While I like the FI, it doesn't take much to **** it off, lol

nasty98z28

No welding, it's a factory ecu. I did not touch anything on the car, I was making a pull, exhaust blew off. The problem was either from, installing the new 255 or the exhaust blowing off. I installed the pump, started the car and left to make a pull, these both happened within a few minutes of eachother so hard to tell which effected it.

I attached a picture of a good log vs a picture of adding fuel.

nasty98z28