i have a 1998 mustang cobra that has the check engine light on.the technicians read the codes and got running lean in bank one and bank two i had them due a diagnostic on it and they said that they tested it with propane and that the rear of the lower intake manifold was leaking so i have no idea whats going on any help would be appreciated
i changed the two before the catalytic converter with brand new
Bosch ones but the two after the catalytic converter are denso and are a bit older also the idle goes high like 1500rpm and takes a long time to go back to normal idle then it goes below normal like 400rpm but only when i drive the car hard
i finally took it to the dealer and they told me it was a vacuum leak in the intake manifold gasket and that i need the imrc plates so i was wondering if i should delete them or replace them with new ones and if anybody knows a good mechanic in los angeles
seems like a problem very similar to what i'm experiencing also. i just replaced all my gaskets on my intake manifold and an o2 sensor and cleaned my MAF sensor. still got p1151 code. i was told that that code will go away if i drive it about 50 miles. this is what's keeping me from passing emissions. will IMRC deletes cause CEL to come back on or fail emissoins?
thanks,
alan
well my problem got fixed i did all the things you did cleaned the maf bought oxygen sensors i then took it to a shop the guy told me the maf was super dirty so he had some special cleaner and he cleaned it it now runs better with no codes also he said if it does the same thing just replace the maf trust me i took it to the dealer and another shop they told me i needed the imrc plates and the gaskets which was not true. actually the imrc are required for emission purposes and i think you have to tune for deletes and get a scanner to turn off the cel
1998 mustang cobra running lean 
