1999 Mercury Grand Marquis LS, 4.6L V8, 220,000 miles
Originally the check engine light came on showing an error code of P0174 – engine too lean bank 2.
The shop that we took it to said that it could be one of three things, because the engine is getting too much air and not enough fuel.
- Air conditioner malfunctioning
- Fuel filter needs replaced
- Car needs a tune-up
All of those items have since been done. The check engine light went off, for about 2 hours (drive time) then came back on.
We brought it back in and they hooked it up to a diagnostic computer and this time said its the MAP sensor. So we replaced the MAP sensor. Less than 45 minutes of driving, the check engine light came back on.
The engine runs extremely rough. Also lately the speedometer on the digital dashboard has been acting strange. The speeds it displays bounce all over the place, and frequently get stuck at 0.
Although these problems arrose at the same time, the speedometer seems to act up whether the check engine light is on or not.
A video of speedometer problem can be found here: https://www.facebook.com/amy.jo.iannone/videos/10210980608297703/
So I have a few questions now that I seemingly keep poring money into my car but the problem does seem to get fixed:
- What could be causing the check engine light to chronically continue to go on, and the car to run rough?
- What could cause the odometer to not work correctly?
- Is it likely these problems are related?
- I love the car, and I have poured a lot of money into it, but it does have a lot miles, is it perhaps time to look for a new car (meaning do these problems sound so serious that its just one of those situations where the car needs retired)