What are some symptoms of a bad one??

 

Two quick ones are loss of power and poor gas mileage.

 

I've heard that when they go its like night and day. The whole car will all the sudden feel very weird, hesitation and like shoebox mentioned, very bad gas mileage. Disconnect your MAF and if your engine barely runs, most likely your MAP is dead.

 

When mine went out,the car would spit and sputter,and was undrivable,but it would idle,but try to give it gas,and it felt like distributor probs.Driving down the street it would buck,and miss under load.(had it towed to the mechANIC ,and all it was is the map sensor.)Last week had the connector replaced(leading to the map sensor),it was toast.My02

 

the easiest way to diagnose your prob would be to hook up a scan tool to your car and or get whatever codes you are getting out of the car. If you don't have access to a scan tool than you can back probe the map sensor with a volt meter. If i remember correctly your voltage should go up towards 5 volts as your vaccum goes down. Either way you should see a smooth voltage change between 1volt and 5 volts as you bring your rpms up. A lot of similar symptoms can be caused by your ect sensor and/or your tps so its I wouldn't call the map the culprit at this point. Most of the time when a sensor dies the car ends up in a very rich mode causing it to run bad and die on ya.


Good Luck mike