Ok I have a 1988 firebird that use to have a blown 3.1 in it and i got a really good deal on a 2.8 from a 86 firebird. The swap has been done for over a year now and engine runs fine only recently it has been acting up. On colder mornings when first cranking the car the rpms rise way up to 3000 then drop back down to 500 and sometimes it will die, but when it does not die it rises up and down for a few min as it warms up the more it warms up the the lower it rises until finally it stays at a constant idle. Second while accelerating say i start out at 25mph and push and hold the gas pedal half way to the floor the rpms drop and stay at like 1500rpms and after about 5 seconds its almost like i can feel it get little bursts of power and slowly it will begin to get going, usually once it hits 3000rpms it really opens up the rest of the way. if I put the pedal to the metal then it will jump into passing gear and accelerate with no problems. Some modifications i have done are: custom CAI, ford injectors (i believe they are E67E-9F593-B1B), paceseter headers, almost all sensors are fairly new, due for a transmission fluid and filter change not sure if this will affect anything. PLEASE ANY INFO WILL BE GREATLY APPRECIATED!!!!!

 

Anyone...

 

Don't know anything about the mods you got bmx, but your 3000rpm then drop to 500 sounds alot like what my car has been doing. see my post (Engine fitted (and new freeze plugs!) but won't run!) post. I also have new sensors fitted, these being the knock sensor, coolant temp, EGR etc.
My problem I think is due to a bad air leak in my LIM, don't know if that helps at all but the symptoms sound similar and might be a place to look.

Speed.

 

Ok so I cant really tell if it is sucking air from the LIM, although i was thinking maybe the injecctors are wrong for my car does anyone have any information on the ford injectors listed above?