[m52b28] e30 swap problem

[Edm4]

The engine works fine, but if i press gas pedal equivalently (like cruising through) the engine's rpm minimizes till 1000 rmp, starts to detonate a little and i hear air intake noise, after releasing
throttle pedal, the rpm rises till 3000.

It has m50 intake manifold and throttle housing from b20 'sport air filter"

The motor was swapped before in another e30 i just bought the whose swap from him, everything vent fine on the other one e30.

Maybe ther are some holes in m50 intake manifold which were vacuumed and now one of the vacuumed hoses has been pulled out?

[rich318i]

get brake cleaner and spray it around the manifold if there is a leak you will find it easy cos the enigne sound will change. or pay 4 a smoke test

[Edm4]

Have bought engine starter spray for carburator gonna do it tomorow.
Some thing more: on m52 intake manifold, temperature sensor must be connected?

[rich318i]

the m52 body dont fit 100% to the m50 manifold thats ur problem mate if thats ur spec. no dont disconnect any thing also keep it bmw spec for sensors

[Green]

There's a couple of vacuum pipes that need to be blocked off underneath the m50 mani. Check this guide to make sure everything's ok on the mani

http://www.e30zone.net/modules.php?name ... 24&start=0

As said above check for air leaks with some carb cleaner or similar substance, does sound like a leak.