The car runs fine for a few minutes and then it tends to bog for a few seconds and then suddenly BURST forward, then bogs, and then burst forward...

this started after swaping my engine... only thing i switched was the intake manifold from my old engine to my new one.. all my sensors all worked fine and the car idled fine... i replaced the spark plugs and even used my original distributor..wired to my msd box and external coil ... but when even giving half throtle at low rpms it bogs.. feels like its engine braking.. then it burst forward... i also got a check engine light for oxygen content and electronic idle control.. the car is a 1995 LS and the engine i put in it is a 94 b18b

 

but wen giving it full throttle the car is fine and drives great!!

 

upzzz!!

 

wat exactly is the code description? until then... i would focus on ignition. was the msd box professionally installed? you try restoring the ignition system back to stock?

 

i thought about that but the ignition was fine before i swapped the motor

 

Does it feel like ur getting rear ended, it kinda sounds like ur throttle position sensor

 

Yezzz exacly it feels like im getting rear ended!!! lol you gave the besst description... well im gonna adjust my tps and see what happens!! thanks!!!

 

yeah might be tps i was having the same problem a few weeks ago when i changed intake manifolds

it actually kinda starting doing that again today but went away. also ive been getting a CEL when i start the car and its cold, but will go away when the car is turned off so i couldnt get a code. whats the code number you are getting??

 

i get that too, and i think its cuz of my IACV

 

Glad I could help.

 

i adjusted the tps and it solved one problem it idles better but wen its warm but still ildes high like at 2,500!!!! and surges then drops to normal from time to time so im gonna replace the iac and see wa i get

 

had the same problem on my 98,,turned out to be the oxygen sensor even though it was not throwing a code for it....start there

 

might want to check hoses, the nipple on my TPS was brkoen and there was a mad leak, would rev high then drop then high then drop until i put it in gear or stopped the car. check hoses

 

UPDATE!! i grabed an iac valve from anotha manifold and cleaned it and put it on my car and the problem is solved no more surging!!!! the car feels way better... idles smooth except wen i turn on the radio or the fan turns on the idle drops like its about to turn off but picks itself back up to normal

 

i got a q? can u adjust tha iac. or clean it?

 

the iac has to be cleaned