We had to do an engine swap due to a chucked apex seal and no time to order parts and rebuild. We took EVERYTHING off the old engine (which ran fine) and put it on the new engine. We have removed the sequential hardware and wired open the flapper so that we are running twins all the time (was that way before the swap). The car will start and idle fine. At easy throttle, will run up over 6000 RPM with no problems. On hard throttle (or under load), it will lay down at atmospheric pressure (transitioning from vacuum to boost). It feels similar to hitting the rev limiter. Will not make ANY measurable boost. Some info on what's been done so far:
- tested with an auxiliary boost gauge which verified operation of our original
- fuel pressure is good - 30-50 lbs depending on throttle
- primary injectors are firing
- secondaries are not (though it is our understanding that they should not until the engine gets into a boost condition - is that right?)
- we have spark at all 4 plugs
- turbos are spooling fine when we disconnect from the intercooler (intake)
- we tried plugging the BOV lines to see if we could build boost - same symptoms
- checked power to and wiring from injectors to ECU (OK)
- checked every vacuum line (OK, though there is a chance we could have one or more improperly connected - will follow up with a diagram over the weekend - any place we should start?)
- no codes for crank angle or throttle position sensors

My assumption is that a solenoid or relay is faulty (or not properly connected), and the ECU is killing us at boost to prevent damage. But we don't know where to start or what else to check. Any help will be greatly appreciated.

 

Check the wastegate solenoid wiring and routing as well? Verify WG actuator with vaccuum pump and also consider running WG solenoid disconnected to manually test to 7 psi without the ECU getting in your way. However - you probably still should be hitting 7 psi but I would head in that general direction.

Yet another reason why single turbo is the way to go eventually - KISS.

 

Thanks. That is where we'll start. If interested, I can post the solution (if we know what it is by the time we get done). Greg