I have a 99 1.8t it says apr1 bar on my ecm and hits 20psi but since the battery died it has lost a ton of power but still hitting 20psi just bought the car and already had upgrades on it looks like just the ecm and apr exhaust.
any help tuning plug gap fuel pressure ect... before the battery died it would cut out at high boost at low rpm.

 

When the battery died did you make sure to turn the key to the ON position for 30 seconds before starting the engine for the first time?


If it was cutting out before it most likely just needs new spark plugs that should be gapped around .028-.032.

 

read the stickys and search for boost issues!

 

Unhooked battery for about 1/2 hour and left key on for 30 seconds before starting. No change, I also pulled the plugs gap was at 40 took them down to 30 smoother accel but still not the power it had. Was looking on line about apr chip says it can have diferent programs tried there cruise button way to change it but does not flash the engine light like it calls for. would the battery being removed set it to default?

 

Yes if it is an APR chip with multiple programs it will in fact go into a default "stock" setting if the battery is removed.

 

I also have a 99. When I got the APR chip put on my car they had to install a push button switch in order to change the programs. Mine was installed under dash right below the steering wheel. Take a look around and see if there are any unusual buttons any where.

 

Correct. They also installed buttons near the ECU. IIRC the cruise control only worked for the APR chip on the DBW cars.

 

looked everywhere no button found. There is alot of wires under the dash leds,alarm,stereo the prev owner had in it so I'm going to pull the lower panel off and get rid of most of the junk maybe the button got tucked under there.
looking through the other threads and my car mybe a 99.5 if that makes any diferance. Build date 3/99 one piece headlights and longer side markers, maybe just mods, but look stock.