Stumbling, missfire, A\F Ratio off? Help!

[wrknmike924]

So i have finaly found some time to mess with my own project. A turbo 420a. Heres the problem

I have a known exhaust leak which i will be fixing soon.

Start the car, run for 20 seconds and it will start stumbling or looping. I am running the portfuler setup and also stumbles out of boost. The second i hit boost it clears out.

Currently only have a narrow band gauge but i want to fix this problem before i go drop a few hundo on a wideband. At idle the car should run as stock.

I have changed all the sensors on the intake, have a new cam and crank sensor, changed plugs and wires.

I have also bypassed the portfuler system to check for a leaky injector. Still no go and i am out of ideas. Really need help because i am at the last step until i can drive this thing and i just want to get her back on the road.

Thanks in advance guys!

 

[Locke]

Look for vacuum leaks where the IM mates with the PF injector block thing, and where it mates with the head.

 

[wrknmike924]

Checked that out. All bolts tight, no leaks. Also ran over the whole motor with intake cleaner trying to change the idle looking for a leak. no go. Still pulls a vac on my boost gauge. No diffrent than before.

Truly out of ideas. Anyway i have so many things running off vac now that my intake is too small?

Thanks again.

 

[dsm9]

by A/F ratio off do you mean its not showing a number? if so the car is probably too lean at idle which will cause the stumbling.

 

[wrknmike924]

My air/fuel ratio according to narrowband is reading right at rich. I have not invested in a wideband yet because i need to know if i need the few hundred bucks to fix this problem.