power loss in 87 325i

[mathillois]

my brother got in an accident and its up to me and my dad to figure it out since all the mechanics in my area cant figure the issue. the car starts fine but bogs when accelerating. can't go over 30mph. my dad said that it starts really strong when first cold then starts to get rougher when warming up.
whats been done:
-smoke test
-new distributor cap and rotor
-new intake manifold gaskets
-new idle control valve
-new ignition coil
we dont really know where to look and unless new information comes up, we ll be focusing next on fuel: pump, filter, injectors, lines.
anyone have an idea?

[Regnar75]

first start by telling us what kind of damage was done in the accident, then start by eliminating possible issues with fuel, air, and spark. although it starts and runs i would do this first anyway. what does it do when you try to go over 30mpg? buck? shut down? choke? does it matter what gear your in or is it just 30mph all together?

if you did a smoke test and no leaks were detected I would try and use a known to be good AFM (especially if you had front end impact) AFM issues are usually apparent upon acceleration. also check to make sure your CPS was not knocked around or loose. while i dont think that is your issue, it may be and i've seen it happen before.

hopefully just doing the first step and checking off individual fuel/air/spark components you will find the problem and not have to chase replacing parts.

[George Sydney]

it stops like 200 rpms higher then drops down a half second later.we also replaced the fuel pump cuz it nearly failed and the fuel filter wasnt in good shape.we replaced it with a 91' bmw 325is pump.the engine is out of a 87 is and the cpu and harness is a 91 325i.the plugs and wires apear to be newer.and i cleaned off the corrosion in the cap.it did help some with the shimmy and the power loss but only mildly.the car is still lacking power and shimming.and the check engine light blinks on and off sometimes.

[mpowerful]

Stomp test it. Itll have a code in memory.

[mathillois]

he swerved off course and crashed on in a ditch. the most apparent initial damage was a broken oil pan and oil pump. we fixed that and then noticed these symptoms. the smoke test found leaks all around the intake manifold, when i was working on it 3/4 of the bolts were loose. thats why i put new gaskets on the intake manifold.
it doesnt shut down, once it reaches at speeds of 20-30 it will all of a sudden loose all throttle and buck like you said i guess, and then works its way back up.
we have a backup AFM and tried that one on and the issue remained the same.