1997 Escort with surging RPMs, code P1131
 

I have a 1997 Escort LX Automatic Wagon With 123,000 Miles. I Have Had Code P1443 (EVAP Emissions Control) Code Appearing On And Off For 6 Months With No Driveability Issues, So I Ignored It Since It Passed The PA Emissions Inspection. Within The Last Month, I've Been Experiencing Intermittent Issues With The RPMs Surging While Driving. It Starts Up Fine, But Usually Once Per Day I Can Feel The Car Stumbling And The Tach Goes Up And Down - Feels Like It's Going To Stall, But Never Does. While It's In This Mode, I Can't Accelerate And It Usually Lasts For Only 1 Minute. It Seems To Happen Whether The Car Is Cold Or Warmed Up. Having The Heat Or Defroster Turned On Makes The Problem Worse And Fuel Economy Appears To Have Dropped From ~27 Around Town To ~24. Today I Checked Codes Again And Got The Original P1443 And Also Code P1131, Which Appears To Be The Upstream O2 Sensor Indicating A Lean Condition. I've Read Lots Of Comments On The Web About How To Resolve A Code P1131, But They All Seem To Point To Different Hardware Depending On The Symptom. I'm Hoping Someone With Experience With My Particular Symptom Can Advise On The Best Place To Start. Maybe The Two Codes Are Related? This Has Been A Great Vehicle For Me, But Every Repair Needs To Be Weighed Against The Value Of The Car At This Point. Planning To Up-size To A TaurusX Within 6 Months To Accommodate Growing Family.:)

RE: 1997 Escort with surging RPMs, code P1131
 

Check the lines at the canister purge valve to intake for cracks or damaged/rotted hose, or could be a bad valve.. Fairly common, and if unmetered are enters the intake can set a lean code as well as cause the surging..

RE: 1997 Escort with surging RPMs, code P1131
 

Here's a pic of the canister purge and the flow sensor..In line withthe EVAP canister

[IMG]local://upfiles/6756/D31138EE0E3E4B1886D90383CA85A438.gif[/IMG]

RE: 1997 Escort with surging RPMs, code P1131
 

Thanks for the quick reply. Did some checking and it soundslike the best way to inspect this equipment is to take the front passenger wheel off and remove the splashguard. Hopefully I'll have the chance this weekend. The lines are original so I'm sure they're not in great condition. I may justreplace the valve and sensor while I replace the lines just to avoid having to go through the procedure again. Looks like the parts are ~$60 total.