2003 Town & Country running rich
 

2003 town & country with 3.3 liter flex fuel engine runs rich and has p1297 map sensor code. replaced map sensor still same way.has 5 volt reference and good ground to sensor plug.

1. Check your air cleaner and any restrictions in air flow

2. Check your exhaust system has no blockages causing high back pressure . A collapsed catalyst matrix can do this.

3. Check your O2 sensors

4. Take out your plugs and read them - they should be nice and grey/brown. If they are black and sooty or wet you have a problem on that cylinder.

5. Check your compressions on each cylinder

6. Check valve clearances when cold to ensure hydraulic cam lifters are releasing correctly.

7. Check resistance of plug leads and check distributor cap/rotor arm. Check quality of spark on each plug.

8. Check for binding brakes or any other possible cause of resistance to movement e.g. too much oil in transmission of it is an automatic.

9. Check fuel pressure bypass valve and check fuel cap to ensure air bleed is not blocked.

10. Run some injector cleaner through the tank OR use some carb cleaner (must be catalytic converter safe) into the air filter housing to dislodge any varnish that may be causing an injector needle to stick.

Mine did that also when I had EGR gasket issue. In my case I noticed missing EGR gasket and replaced it which caused the SEL to kick on a 1297. After running engine for some time and clearing the code all was well again. Strange how the SEL never came on with "missing" gasket.