Engine Performance problem
2000 Dodge Caravan 6 cyl Front Wheel Drive Automatic
Hi Bob and Ken,
Does a MAF sensor does something to make the hydrocarbons high? And where do I start to check for a vacuum leak?
Thanks once again because all your advices are so helpful and hoping for your most appreciated reply once again.
Yes. Any unburned fuel that escapes through the exhaust, is called Hydrocarbons(HC). I have been dealing with hydrocarbons for the State of New Jersey for as far back as 1983. A spark plug, wire, any secondary secondary ignition problam will cause a misfire and high HC's, a state failure for emissions testing. Of course a mixture that is too lean will have an incomplete combustion, causing the same problem, especially with a Mass Air Flow type of fuel injection system. The areas to look are vacuum hoses, intake manifold leaks, EGR leaks, positive crankcase ventilation system leaks, and many others. I sometimes use a tachometer, and a spray bottle to check different spots for changes in RPM's while engine is running when I spray water, or carb. Cleaner lightly in spots.
Any loose clamps in the air intake, before, but especially after the air flow sensor. A leak down test can also be used. A good visual check is first. I hope I have helped you in some small way.
I appreciate you.