No Power Until 4K Revs

[firstcar_205gti 2 1 Cars]

hi guys I've recently fitted a new engine in my car and since I've put it in its been running like dog... when you start it it runs fine but you can hardly rev it all (misfire) when it warms up it drive fine idles ok ish but on full throttle holds back quite a lot until you get to 4k revs then she goes like the wind! I've checks all wires etc ht leads and all that haven't found anything, spark plugs look ok but sooty. also when you try full throttle you get quite a lot of black smoke

[DamirGTI 342]

If the plugs are black/sooty , and if theres black smoke from exhaust that indicates rich mixture .. so start from there .

 

Check the AFM and ECU temp. sensor (replace it as it's really inexpensive part which if faulty over-fuels engine badly) , also check if you haven't by mistake mixed connectors from the SAD heater to the ECU temp. sensor ie. plugged them other way around as they're both 2pin connectors one black and another is blue - blue connector goes on the ECU temp. sensor , black one on the SAD heater element ..

 

Check also for air/vacuum leaks , and try playing a little bit with ignition timing (advance it a little and see if it then runs better on mid range)

 

D

[firstcar_205gti 2 1 Cars]

ive checked the plugs and there where all fine and in the right place on sad and temp sensor, I've got another afm hanging about tried it and it revs better and no black smoke, but now it won't idle what so ever, even if change idle on the throttle body this afm is from a 1.6 if that matters. connor

[ALEX 98 1 Cars]

Vac advance stuck open?

Dizzy adjusted correctly?

[Anthony 1,003]

If it's much better with another AFM that suggests that the original AFM is goosed.

 

It not wanting to idle on the new AFM might be partly down to it being incorrect and might be that it just needs setting up properly in terms of mixture, idle speed and ignition advance.

 

Was it a running engine in the donor car and if so, was everything like the dizzy left untouched prior to fitting it into yours?

[firstcar_205gti 2 1 Cars]

thanks guys I've set it up properly ish and runs fine thanks for help