I finally got off my a** and installed a turbo on my ED, im running an EMS 8860 with a 'Turbotrana' base tune. Anyway it started all good and then idled fine until it started to get warm, at that point it started surging from virtually 0rpm to 1500rpm and continues to do it until it stalls (usually after a half a dozen surges) I can get it to idle if I hold the throttle, but is very laggy.

I thought it was a vacuum leak as the MAP hose was split on the end, but fixing that didnt help. I also thought it maybe the ISC as it makes a rattling noise when the ignition is on, but there was no effect when I disconnected it.


Any ideas?

You need to tune it. There is nothing wrong, when you put the turbo on it has changed the fueling requirements and it needs to be adjusted.

You need to get a wideband connected and learn how to use the autotune feature on the EMS8860.

This is something that you can easily tune yourself.

Its probably running in the lean area so the easiest way to get it running a bit better is just to "trim" the fueling up till she settles.

It started fine because the choke (extra fueling) was on when cold.

But you really have to adjust the fueling map to the desire Air/fuel ratios. The n/a tune is a good starting point.

I'd say turbotrana is on the money.
Stay with it man you'll get there.

the ecu dosent know what to do yet