map sensor problems

[d_tuck]

i picked this car up from a friend who replaced the engine with another one just like it. i had to redo the entire vaccum system he had it all messed up according to the diagram and that didnt help it. when i plug the map sensor up it seems to lean out some but the idle goes up to about 2k. i checked the map sensor voltage i have 5v at the cpu and 5 at the plug under atmospheric pressure when i simply plug the map back in the voltage drops to 3 volts. is that right? the computer is kicking the map sensor and the coolant temp sensor codes the coolant sensor is new the car has overheated a time or 2 on me i believe because it didnt have a thermostat in it when i bought it i put one in and apparently didnt blead the system correctly any help would be greatly appericeated

[328FTW]

Is it leaning out under hard throttle or partial throttle, maybe both?? Your map sensor is probably right but if the Throttle Position Sensor (TPS) has been ****ed with it may think the throttle is at less than it actually is leaning it out. Also it would help to have all the little sensors fixed as well they can add up to one big headache. Could also be a bad O2 if it happens when your under full throttle, hard to tell from the description.

[d_tuck]

Originally Posted by 328FTW

Is it leaning out under hard throttle or partial throttle, maybe both?? Your map sensor is probably right but if the Throttle Position Sensor (TPS) has been ****ed with it may think the throttle is at less than it actually is leaning it out. Also it would help to have all the little sensors fixed as well they can add up to one big headache. Could also be a bad O2 if it happens when your under full throttle, hard to tell from the description.

with the map plugged up to vaccume idle goes to like 2k and leans out u give it gas it seems to break up the coolant temp sensor is new. you unplug the map it goes back to idle but puffs black smoke seems to break up over 2500 steady. but revs fine just smokes alot with awful economy

[328FTW]

Unplug your TPS and leave the map plugged in then try it again, with the TPS unplugged they are not the most fuel effecient of things but it can tell you if its badly adjusted or fizzed. You can do the same with the O2 its just a cheap way to check them without a miltimeter or engine diagnosis machine.

[d_tuck]

Originally Posted by 328FTW

Unplug your TPS and leave the map plugged in then try it again, with the TPS unplugged they are not the most fuel effecient of things but it can tell you if its badly adjusted or fizzed. You can do the same with the O2 its just a cheap way to check them without a miltimeter or engine diagnosis machine.

i unplugged the tps...it didnt change a bit not even for a second

[d_tuck]

ok it idles high with the map hooked up and still a little rich its tripping map sensor and coolant sensor codes but engine light does not come on unless you actually unplug the sensors.there is a 1 wire sensor for the coolant guage ,the bsvs ,and then there are two 2 wire sensors all on the coolant neck the 1 wire sensor was put closer to the fill cap.looking on the old engine there was only one 2 wire sensor. there are plugs going to all of these and vac. going to the bsvs.when i unplug one of the 2 wire sensors the engine light comes on when i unplug the other 2 wire the light is not affected nor does it trip any other codes.what are the possabilites im running out of ideas