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1995 Jeep Grand Cherokee Repair Question


Topics covered: Engine, Smell, Black smoke.
Mileage: 170,000 miles.

Asked on October 22, 2012

Jeep Grand Cherokee Engine Problem

In town mileage dropped to 5 mpg from 18 mpg. Highway 20 mpg. No check engine lights.
Avatar Asked by (pending member)

Answer

Replied on October 22, 2012

Look for a fuel leak. The Engine Computer can only modify fuel metering by plus or minus about 10 percent so even if it was getting incorrect information from the map sensor, fuel mileage would only drop by a few miles per gallon. To be getting only five miles per gallon with no leak, you would have to just about have raw fuel dripping from the tail pipe, and there would be a lot of black smoke from the exhaust.

Look under the vehicle for wetness, especially along the right side. Pull the vacuum hose from the fuel pressure regulator to see if it's wet inside. Smell the oil on the dipstick. If it smells of gas, suspect a leaking fuel injector, but that is real uncommon on Chrysler products.

Tiny Answered by caradiodoc (expert)
17,277 answers provided