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Car Vibrations and poor gas mileage

I have a 98 Ford Escort with a new Jasper Engine amd a catalitic converter. Before the new engine I would get about 30 to 37 mpg. Now I get between 15 and 27 with an average of about 25 mpg. Recently the car started to vibrate and “occasionally” I can smell gas. After looking, a motor mount had to be replaced but the vibrations were still there. After 5 mechanics looking, none can decide what is wrong with my car. Belts are tight, timing good… blah blah blah. The vibrations that the car is making would make a whore happy. Can anyone tell me what is wrong with my car?

If you have a distributor, the wires are going to the wrong plugs. The firing order is usually 1-3-4-2 and you have to look up the rotation direction. If you don’t have a distributor but have plug wires, they could still be wrong.

The instructions for removing and installing the distributor on your four cylinder, 1.8L, Escort: http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528008da49
Firing order and checking distributor position:http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528008d9dc
If the distributor cap has some age on it, replace the cap and rotor. And, replace the spark plug wires, and spark plugs, if they are aged.

great idea, but I have an entirely brand new engine. Could the mechanics just used cheap wires?

I can’t see this being a firing order,plug wire or spark plug problem. If you had a dead cylinder in a 4 cyl engine you would be doing more than complaining about a vibration and poor mileage.

I would like you to explore this “occasional gas smell” more. It doesn’t sound good (in regards to the mechanics you have chosen) that they installed your new engine and did not detect a bad mount at installation time. What other mistakes (diagnostic) have they made or are making?

Is Jasper the company that provided you with the engine? I am suspicious of a possible error made when transfering the old engines external components to the new engine.

The problem might be caused from a leaking fuel pressure regulator. When this happens, excess fuel gets drawn into the engine resulting in poor fuel economy and the odor of gasoline. Remove the vacuum hose from the fuel pressure regulator and if there’s gas at this connection the regulator requires replacement.

Here’s what the pressure regulator looks like. http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528008dd37

Tester

Thanks for this info…I’ll tell my mechanics and get back to you with the results

Depending on the transmission your car is rated for 22-34 MPG. The automatic rated for 22 MPG city 31 highway. 25 MPG sounds about right.

As for the vibration it could be a number of things, a bad plug wire, a bad harmonic balancer (your engine may not have one), or as others have pointed out a bad fuel pressure regulator.