Ford Escort 1.6 Zetec SFI multipiont 1998 L1 - Rising and falling idle speedArchived Message
Posted by Alan Marklew on August 11, 2005, 6:06 pm
Hi had this escort in this week, costomer complained of rising and falling idle when first started in the morning, for about 1 1/2 mins all data seemed ok apart from the o2 sensor was locked lean. checked all usual things IACV, TP, MAF, vacum,no air leaks PCV valve all seemed ok,so did service items and also changed IACV. still exactly the same, so decided to put it on the gas analyser and these are the results Fast Idle HC = 315 CO = 0.10 CO2 = 11.19 O2 = 4.94 AFR = 18.6:1 Lambder = 1.25 Natural Idle HC = 1360 CO = 0.01 Co2 =8.6 O2 =8.7 AFR = 22.7 Lambder = 1.55 From the data I assumed a lean mixture and checked the fuel pressure and operation of the fuel pressure reg valve, all ok.at this point i turned to the mechanical side thinking that the fuel was getting in, in the right quantity but was not being burnt correctly and suspected valve timming, all ok. Now at the end of my tether and begining recheck things again and again and am probably missing somthing simple. hope someone can help me out of my pergatory, TIA, Alan