Questions and Answers

Ford Escort ZX2 Engine Hesitation Q. I bought this car about three weeks ago. Upon purchase the check engine light was already on, I had the code read and it was P0420 - Cat System Bank 1 Below Efficiency. I had the mechanic turn the light off and it has not come back on. Since then I have noticed that when I am at idle, whether the car is warm or cold, and I give the car gas, there is a slight hesitation, followed by a sucking or hissing sound, THEN the engine accelerates.

I popped the hood and listened while revving and the sound seems to originate from the area where the intake meets the fuel injection system. I have looked around for any loose or cracked hoses and could not find any, if you have any suggestions it would be greatly appreciated.

• 1999 Ford Escort ZX2
• 2.0 liter DOHC
• 5 Speed manual transmission
• 97000 miles
• EFI
• No ABS
• P/S - A/C

Thanks...

A. I'm having trouble picturing "intake meets the fuel injection system" but it sounds to me like a sucked in intake manifold gasket.

What you can do is get a can of carburetor cleaner and a red straw and spray little puffs around the suspect area. When the engine picks up rpm, that is where the vacuum leak is.