I have a customers 1999 Mercury Cougar 2.5l v6. It has codes P340, P420, P171, P1000, B1600 in that order. The customer just bought this vehicle from a used car dealership. It sometimes starts and sometimes does not. It sometimes just dies on the road as well.
Country: United StatesMake: MercuryModel: CougarYear: 1999Engine: 2.5l
Thanks for your question. Sorry you're having car problems. If I go off line, just leave a message and I'll be right back. DO NOT leave feedback yet. The first code has to do with the CAM sensor circuit, either a bad sensor, wiring or computer. The second code is for a bad cat on bank one. The third code is a lean code for bank one. The fourth code is a clear history code, no biggie. The last code is a PATS key code which is most likely the starting problem. Sure hope they got a real good deal on this car, it can be costly to repair. Thanks, Ron
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Thank you, Ron
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I saw you were off line so I had to switch us over to Q & A. I would certainly do some O2 sensor and CAM sensor tests with a scope first, then look for a vacuum leak in bank 1 to start with. Thanks, Ronrpmdiag41113.7305677431
How should I go about diagnosing the problem for the first code P340? Also, does the catylitic converter need a definite replacement? And I will need help diagnosing the PATS issue as well.
You need to diagnose everything with a scan tool and a lab scope to confirm their operation. Don't replace the cat yet until you know for sure that the O2 sensors are working right, again by testing them with your scope. Please don't forget to rate me as high as you see fit and I can still assist you afterwards if you need me to. Thanks again, Ron
I apologize for the late response I was off this job for a day or so. I checked the oil on this vehicle yesterday because the customer called me yesterday to inform me that there is a coolant loss in the system. The engine oil is all milky from being mixed with coolant. Any ideas or suggestions of what to do next?
Sounds like a blown head gasket, we need to get that fixed before anything else. Please don't forget to rate me as high as you see fit and I can still assist you afterwards if you need me to. Thanks again, Ron
37 years experience