I just completeeted a single turbo conversion on my 20b. The car started first time and idled fine, however it would not drive under load. As soon as I go to accelerate the afr jumps up above 15, fluctuates wildly and the car splutters and has no power. I suspect a vacuum leak, however I am after suggestions.

Edit...
I am also still running the factory afm.

 

you can't do a single turbo swap without making adjustments to the fuel system....

*beats head on desk*

don't see FD guys swapping to singles on the stock ECU do you?

depending on the turbo your airflow may be radically different than the current ECU is mapped for, even out of boost, because the turbo is ALWAYS pushing or pulling air affecting your maps.

 

Sorry Karack, allow me to elaborate;

• Computer is a Panspeed ECU with a GReddy Emanage Ultimate.
• Fuel system is 6x 1000cc ID1000 injectors with a Turbosmart FPR2000 and Guru rail kit.
• Boost control via Blitz DSBC (currently turned off)
• Wastegate is a Turbosmart Pro-Gate 48 with 7PSI spring.
• Wideband is a Innovate LC-1 with XD-16 gauge.

Car was working fine, prior to the single turbo.

Now, the AFM is reading consistent voltages - which to me indicates that turbulence created by the new turbo is not the issue.

The wideband is reading crazy figures on even the smallest acceleration under load. I have not taken the car past 1500RPM yet under load. Anything more than 1200 RPM causes wild AFR fluctuations.

So - it seems like there may be some type of leak, so I suppose that what I am asking for is; before taking it in for a tune, do these symptoms sound like there is an underlying issue which will prevent the car from being successfully tuned? - i.e. is this maybe a symptom of a failed fuel delivery component and / or a vacuum leak?

OR is this to be expected given the change to the single turbo - i.e. everything is fine - you just need a tune.

 

i don't know the specs between the twins and your turbo but i would double check your fuel pressure, it has alot to do with how the car will react under a load versus idle.

 

I've got an '84 SE running (it sat for many years) and it ran great. Then it dies and would start and idle fine but it wouldn't go anywhere. Since I was close to home, I turned and held the ignition switch in the start position, it probably killed the starter motor and I have no idea why it worked but I was able to get my car home. I took the inlet line off of the fuel pump and there's a tiny conical filter that goes into the inlet side of the fuel pump before you put the hose on. I was tempted to leave it out but I'm not interested in paying $200 or so for a fuel pump due to my stupidity. I cleaned the filter and it ran well. I filled up the tank and added some additive for cars that have sat for a while. Still, it happened again so I bought an enormous metal filter for the fuel pump inlet side. I think the hose diameter might be either 7/16 or 1/2 inch. I was lucky that the guy at the AutoZone knew they had a filter with the correct size connections. It fits like it's supposed to be there in the little tray that's behind the drivers seat in front of the rear wheel under the car. I carry a spare just in case. I posted to someone else within the last week or so who had the same problem; I wonder how wide spread the problem is. Cars that have been turfed for years; I kind of expect it but if it happens on the daily driver, I don't have a clue.

Ideally, it would be nice to pull the tank, boil it and, I can't remember what it's called but it seals your tank if it has tiny leaks but it also locks in rust and debris if it didn't get taken care of during its bath.
Good luck, a turbo 20B, I'm jealous! Just don't run it lean!

 

Did u ever figure out what the problem was?