[Rammstein353]

today i pulled codes 18 21 and 41.....18 is loss of tach to computer and spout is grounded, 21 is the coolant temp sensor sayin out of range but i just got a brand new one and 41, hego sensor voltage to low system lean....i dont know where to start but im pretty sure my symptoms are cause of these 3 things im getting hesitation when accelerating slowly stalling sometimes bad fuel economy and feels like lose of power not too much though...this just started recently please if anyone can help me out ...85 t-bird 5.0 tbi

 

[89coupe]

First clear codes, by starting the KOEO test, and as soon as the codes start to flash, remove the scanner or test light, which ever one you are using. then turn the key off. test drive for about 10min. hook back up the code reader or what ever and re run the KOEO and KOER test and see what codes you get.