I just had an engine put in my '94 rx7.. when i get it started it idles very rough "like a blown motor" and then eventualy dies out.. i've heard the MAP sensor can cause this to happen.. so my question is how do i check MAP sensor to see if it is the problem?


'94 white
no mods

 

this is a silly question, did you verify that the vaccum hose from the MAP sensor is connected to the UIM?

 

let me look.. i know the vacuum hose is connected to the map sensor.. give me one sec to look

 

yes. the hoses are connected

 

did you just put in d engine yourself?

there are a lot of factors for rough idles... it can range from a simple loose hose to fuel system...and ect... we cant diagnose it until you describe what you did to your car... and hopefully maybe we can pinpoint the problem...

 

no i didnt put it in myself.. the systems it has right now though is that when it does start there is a very rough idel that shakes the car and a white smoke comming out the tail pipe "which as far as i know is normal when starting up an engine for the first time".. the car runs for about 5 seconds or so before dying out and a little longer when give it gas.. any ideas?.. i heard the MAP sensor could cause an idel like that.. is that true?

 

It's true, but it doesn't necessarely mean it's your current problem.

But if there's a problem with the MAP sensor, the turbos are not going to spool for sure. But I'm assuming with this kind is bad idling you didn't even think about trying to actually drive it... unless you're really sick

 

my car starts for about 5-10 seconds and has a nice cloud of white smoke when it does with a strong smell of gas with a very rough idel and then dies out.. and ideas? ... and how do i check the map sensor?

 

i blew my engine last winter and bought a j-spec engine.. i had a shop up the road from my house put in the engine.. also my rmp gauge isnt working

 

You should be talking to the shop that did the install if it's been like this since you got it back. I assumed you paid them for the install. If so, you should get your money's worth.

 

Check that all the connectors on your ECU is properly connected!
When I rebuilt my engine I actually forgot two of them (I know, I know...). This resulted in that the car would start, but after 5 seconds the fuelpump would cut out and the engine would die. I shorted the fuelpump and it would run fine. Took me half an hour to find the loose connectors.
This also resulted in dead RMP-gauge....