I'm driving a 1991 Eldorado (4.9 - 126K miles) - and I can't seem to correct an idle problem. Can feel it when egine is running, but stopped (ie: at a stop-light,etc.). It's a small hiccup/miss feeling. I've changed plugs, wires, checked hose connections, etc. I noticed an error code of E071- so I also changed the MAP sensor. Not sure where else to go from here. Currently, the only code I see now is B121 - which I've had that since I've owned the vehicle. (about 3 years now...). My mechanic seems to be scratching his head on what to do next. Any insights would be much appreciated.

Thanks in advance...

 

have you cleaned the intake throttle? tested coil pack?



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