m50b28 running rough

[iloveshaorma]

hey i rebuilt a m52b28 and transformed it into a m50b28 with:
m50 iron block
m50b20 head
m52b28 rotating assembly
m50 intake
s-tech software
i fixed all the errors like cam sensor failure and maf failure but the engine keeps running rough, the whole care shakes while idling, i checked for icv vacuum leakage the ccv valve is canceled, engine has all it's power runs great wot. what should i check next? also new intake gaskets

[qbuilt]

How did you check for vacuum leaks? The best way is always with a smoke machine. Do you have an air/fuel gauge installed? What is the air/fuel ratio at idle?
You need to be 100% sure there is no vacuum leaks before you start looking at other stuff, especially if there are no codes for the maf sensor, etc.

[iloveshaorma]

How did you check for vacuum leaks? The best way is always with a smoke machine. Do you have an air/fuel gauge installed? What is the air/fuel ratio at idle?
You need to be 100% sure there is no vacuum leaks before you start looking at other stuff, especially if there are no codes for the maf sensor, etc.

i'll ask around to see where i can check for leaks with the smokey thing, could be sparkplugs? also i think my fuel pump or fpr is going bad. when i start it in the morning when it's cold it feels flooded it can bearly make it through 1st gear and when i put it in 2nd and let go of the throttle it backfires a lot till 1000rpms and after 1-2 minutes it goes normal

[10Toes]

hey i rebuilt a m52b28 and transformed it into a m50b28 with:
m50 iron block
m50b20 head
m52b28 rotating assembly
m50 intake
s-tech software
i fixed all the errors like cam sensor failure and maf failure but the engine keeps running rough, the whole care shakes while idling, i checked for icv vacuum leakage the ccv valve is canceled, engine has all it's power runs great wot. what should i check next? also new intake gaskets

I dont think the M50b20 head will flow very well for a 2.8 but that's probably not why its running rough.

Do you have the right temp sensor for the DME?

[iloveshaorma]

I dont think the M50b20 head will flow very well for a 2.8 but that's probably not why its running rough.

Do you have the right temp sensor for the DME?

yup right sensor it's a high compression engine and it works perfectly in high revs not so much in the low's but in the highs it's fast like a mofo, i found the problem. the throttle body was of the old m52 and i had an m50b25 intake. the throttle body had groove for a gasket so did the intake. is the m52b28 tb smaller then the m50b25? should i change it? for the moment i put 2 gaskets and it seals good

[cormier]

Ya it's obd 1 vs 2. You can use an adapter plate (basically a thin piece of metal that both gaskets seal to) or switch TBs

[iloveshaorma]

Ya it's obd 1 vs 2. You can use an adapter plate (basically a thin piece of metal that both gaskets seal to) or switch TBs

i'm talking about a smaller diameter on the obd2 tb