99 rodeo engine swap nite mare

well its not that bad, i did a motor swap on a 99 rodeo the car starts up and runs but has a definate mis at idle , the owner of the rodeo , ran it out of oil and by the time i saw it, it had a hole in the oil pan . so a used 60,000 mile motor later , and here i am the thing misses at idle and runs smooth off throttle , any suggestions ? comments ? blatant insults??? all are appreciated thanks in advance . tom

any obd II codes? did the salvage yard do a compression check?

i did a compression check this morning , 150 across the board , there is an o2 sensor code and a random multiple misfire code all of the odd numbered cylinders (on the passenger side head )are missing according to my sca nner

try squirting carb cleaner in the intake manifold seems. if it stops missing right away for a second then you got a bad intake manifold gasket. po 300 usually indicates a bad i.m.g. in 98 and up rodeos (some of the time). some other codes that pop up to indicate a bad img are in the po 17o range and up.
i am not saying it is an bad img just very possible since the dual cam 3.2 from 1998 up eat them alot. since you mentioned the passenger side head make sure you diagnose that img more carefully.

look up in the F.A.Q. section at the top of the forum po 300 is discussed in that section more than once.

lastly is it physically missing or are you just getting the po 300?

p.s. my rodeo is on its third set of i.m.g.'s. also keep in mind year 2000 and above will throw a p0 300 if you put the wrong spark plugs in! (ask me how i know) they use an ion sensing type spark plug. yours is a 99 but the salvage motor could be from a 2000 or above. in which case you only have around two spark plug choices to get rid on the po 300. one of the two choices is the factory plug at 14$ each. their is a cheaper choice that others on this sight know about. i forget what it is.

i sprayed carb cleaner didnt seem to help , how about timing? could i have one cam off? (passenger side )