Thanks for looking ahead of time. I have an 01 Escape (V6, 4x4) with about 105K. Engine light came on a few weeks ago for the wife while I was out of town. The truck stalled many times at idle and occassionally while driving over the next few days. Autozone pulled the code of P1507, which is:
Vaccuum leak
failed IAC valve
open or short
air inlet plugged

After checking the codes, the check engine light went away and the truck seemed to run like it did before. The only real difference though is a drastic change in MPGs. Before this started up to 20MPG...now between 11 and 14MPG. What the crap? Any ideas?
John

 

Not that this is the solution to your problem but the following was my dilema which as of this morning at -20*F I can say is fixed.

First, my wifes 2001 escape began acting up for her, of course I didn't beleive her because when I was able to check it out the escape was warm and worked "fine".

The symptoms w/no codes, running rough w/very low idle speed at stop lites to the point of stalling. At startup the engine would race at high rpms, I said a fast idle at startup is normal. (3000-4000 when I got vehicle cold is not). No codes.

1st fix attempt was to inspect plugs and connectors, at 85000 miles the gap was in spec and they looked good. I cleaned the boots w/denatured alchohol and put it back together running fine.

Next, complaint cont.. this time multiple cyl. misses stored aswell as other codes P1131 and P1151 (HO2s11,HO2s21 sensor lean)I replaced plugs and connector and upper intake gasket. #5 cyl miss cont. swapped coils 5 and 6 and miss followed to cyl. 6. cleared codes and car ran great (warm). Proved this to my wife w/test drive and all seemed good.

Next day complaint is the same. I inspected voltages of tps w/graph on scanner, graph indicated small blip and wouldn't rise past 1.03 volts in town test drive. Replaced and all seems fine.

However. the cold start rev and poor idle cold, continued to the nth degree considering severe cold ambient temps. All parameters seemed good including short term fuel trims of only +1 or +2 cold. I replaced the IAC solenoid as a guess. (wrong guess).

Finally w/use of propane, and carb cleaner and monitoring O2 sensor outputs drastic changes occured in voltages. These changes went unnoticed as far as idle changes of less then 50 rpm. The location seemed to be the area of the intake flanges. Realize the upper intake gaskets were replaced when plugs inspected and changed. I disassembled the upper and lower intakes cleaned and replaced the lower intake gaskets aswell as the upper. At startup and testing the rubber elbow on upper manifold collapsed now. (must have great vacuum now) Replaced it too.

The only difficulty in this repair is that the connectors on the injectors do to continuous high heat, break the lock when depressed. I have assembled w/the addition of electrolite on the prongs and thus far the connectors have remained in place. The fuel economy improvement can't be varified since I am on the most recent tank, I am not giving back the escape w/a full tank of fuel. (Gotta continue to test drive to make sure all is good for my wife.) She can fill it up when I return the vehicle.

Bottom line is that vacuum leaks can be very elusive, check all hoses visually hot and cold, if any repairs made to correct vacuum leaks check the hoses again for collapse. The 5.4 L navigators w/32 valves have similar rubber elbows that connect mannifold to pcv. My fix is a 90 * spark plug boot since the nipple is greater than 9/16 on one end and 3/8 on the other and the ford dealership doesn't stock the replacement assy.

Hope this helps good luck.

 

In my previous response I did not indicate that I had replaced the #5 cyl coil. The cost $136.00 from ford. I didn't specify why when lean codes came up I went to the spark plugs and spark plug connectors. It is my experience when a spark plug misfires the O2 sensor will note the condition as lean. The O2 sensor votage does not realize raw unburned fuel as rich the relative amount of oxygen is relayed based on voltage created. Therefore the most reasonable correction seemed to be plugs and wires (when no codes present)or rather connectors and boots for the C.O.P.

The cost of the IAC was $65.00 aftermarket a bad guess based on trouble shooter protocol. The TP sensor was $44.00 aftermarket (not the culprit but flaky so I'll call it a good replacement decision). The platinum spark plugs are Motorcraft as are the boots and connectors. I believe Motorcraft spark plugs are your best choice if you ever need to replace. The Fel Pro lower gasket set came from an aftermarket parts house for under $20.00. I have temporarily replaced the 90* rubber vacuum boot with 1/2" od heater hose and home made spring inside to form the bend w/o collapse.

Some times codes are used for reasons to replace sensors or actuators. Sometimes previous experience dictates, right or wrong. I hope you take the info I have provided w/a grain of salt but the symptoms NOT nessesarily the codes were similar and as hard as they can be to find, vacuum leaks have to be top on your list. Take care, please post an update when you find the solution.