Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!

2011 Ford Escape Surging/Stalling No Codes

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1 year 5 days ago #60663 by alades
I have a 2011 Ford Escape with a 2.5 liter engine that I am working on for a friend. The vehicle is surging and then stalling when put into gear, turning on the A/C, or turning on any accessories that place a load on the engine. The throttle body has been replaced twice and it still has the same issue. The learn procedure for the throttle body has been performed when both new parts were installed. The MAF sensor has also been replaced. The vehicle was taken to a dealer and diagnosed with a bad torque converter as being the culprit, however, I disagree with that diagnosis because the engine stalls even when in neutral when turning on any of the electrical accessories or A/C. The engine begins to hunt for idle by surging and dropping below the desired idle speed and will eventually stall while under a load. When in park or neutral and no load on the engine, the engine idle fluctuates a small amount but not enough to be of concern. The fuel trims seem to be normal and there are no codes present. Before this issue happened, the vehicle had a burnt exhaust valve replaced a month prior. Also, test driving the vehicle it appears as if nothing is wrong until you come to a stop and then the engine stalls. The surging/stalling issue also only occurs after the engine is completely warmed up and is not an issue when it's cold.

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1 year 4 days ago #60664 by Paul P.
Sounds like a fun one!!!!

Are you able to verify the to TCC slippage is under 50 rpms with a scan tool? Just to eliminate what the dealer has suspected.

Do you have a scope? This could be very usefull to monitor what the PCM is "seeing" during the surge/stall.

Monitoring various inputs could prove usefull to see what's missing during the stall. IE, Crank and cam signals, ignition coil feeds, injector feeds.

With a scan tool what is the Injector Pulse width and MAP signal doing during the surge/stall?

Just because the TB is new doesn't mean it's good, Scope the signals on the TB and APP during the stall as well.

Some times when it's a no code present, we just test what is good to narrow the path to what may be bad.

Try removing the accesory belt too and recreate the stall condition.

Never stop Learning.

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1 year 4 days ago #60666 by alades
Although I can check the TCC with a scan tool, I don't really suspect it as the culprit because the stall condition occurs when in park or neutral when the headlights, blower motor, or A/C is turned on (anything that puts a load on the engine). Also, the stalling issue does not occur when the engine is cold. It only occurs once the engine is completely warm. As far as the throttle body goes, I plan to replace it for a third time tomorrow, only this time, I will be doing it with an OEM Ford one from a dealer as I've had issues similar to this in the past with aftermarket parts. Identifix is usually my go to when it comes to troubleshooting issues like this but I can't find anything pertaining to this particular issue. Thanks for all your help!

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1 year 3 days ago #60678 by Tyler

As far as the throttle body goes, I plan to replace it for a third time tomorrow, only this time, I will be doing it with an OEM Ford one from a dealer as I've had issues similar to this in the past with aftermarket parts.


Fingers crossed for a fix. :cheer:

I'm following along because I had a head scratcher very similar to yours a few years ago. Same vehicle, engine, complaints. New throttle body of unknown origin. Airflow trim PIDs kept climbing and climbing, never leveled out. :unsure:

While chasing my tail on the idle issue, I ran a relative compression and found a leaking intake valve. Customer didn't like my engine repair quote and left. But I was never fully convinced the leaking valve was causing the idle problem.

Anyway, with your Escape, it may be worth checking physical timing. I know you're not getting any timing faults, but that doesn't mean the engine is in time. It's possible to have the crank reluctor and the camshafts in time relative to each other, but still have the crankshaft out of time.

Last idea I have is the purge valve sticking open. Might be worth a check, despite the good trims and no EVAP faults.

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1 year 2 days ago - 1 year 2 days ago #60687 by alades
I have checked the TCC slippage and have determined that everything is within manufacturer tolerances. I finally determined that the engine is actually misfiring on all four cylinders when running it at around 1500-2500 RPM. Cylinder 3 is really bad. I did finally get it to set three misfire codes for a random misfire and cylinders 3 and 4. I replaced the spark plugs with brand new OEM Ford Motorcraft ones with the same misfire and stalling results. I plan to perform a compression test even though I know that one of the valves has already been replaced. If the compression check passes, I feel that I may be looking at a faulty PCM because it should be setting misfire codes based on the number of misfires cylinder 3 has over the last few engine cycles.
Last edit: 1 year 2 days ago by alades.

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1 year 2 days ago #60688 by Paul P.
The engine is misfiring on all four, but three is the worst @ 1500-2500rpm

The misfires clear up over 2500 RPM? and is this no load in park, braked torqued or under normal driving conditions?

What are your fuel trims doing during these misfires? (maybe fuel pressure is dropping?)

These are 2 wire cops, can you verify with a scope primary ignition misfires? Do a relative Compression test with a Spark sync as well.

Any resistance to the crankshaft that can cause a slow down of crank speed could be logged as a misfire by the PCM.

It would be good to verify a good crank signal as well.

Is this a flex fuel?

Never stop Learning.

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1 year 2 days ago - 1 year 2 days ago #60690 by alades
I just took the vehicle for another test drive and noticed that the misfire rate significantly drops when the engine is under a load. To test my theory, I ran the vehicle at around 1500-2500 RPM in park and kept getting misfires, especially on cylinder 3. When I turned on all of the accessories, the misfires stopped. I then turned off everything but the headlights and started getting a few misfires but not a lot. It seems that the more of a load you place on the engine, the less misfires are recorded, even on cylinder 3. Even brake torqueing the engine results in almost no misfires.

I just performed a compression check and ruled out a mechanical issue. Cylinders 1 and 2 had 175 and cylinders 3 and 4 had 180.

After performing the compression check, I swapped all four coil packs around (1 to 3 and 2 to 4) to see if cylinders 1 and 2 started misfiring worse. Not only did they start to misfire worse but all 4 cylinders are misfiring bad, with number 3 still be the worst. The misfires don't start until about 1800 RPM according to the scan data. Looking at the balance test, all four cylinder are contributing equally. If I try to disable one injector the engine completely stalls. This is really weird because the engine stalls at idle under a load and starts misfiring at around 1800 RPM when not under a load.
Last edit: 1 year 2 days ago by alades. Reason: Updated Misfire Scan Data
The following user(s) said Thank You: Paul P.

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11 months 3 weeks ago #60830 by MarkBeck101
This is an over head cam engine which just had a valve replaced, meaning you have to remove the head in order to change a valve. When you reassemble the engine you have to position the timing marks precisly in order to time the engine properly at what is called base timing, which is really important at idle, because if you retard ignition timing from base timing the engine torque drops very quickly (especially for a 4 cylinder engine) and in a non-linear fashion. When you go up in RPM and load the timing will advance and can swamp out a mis-timed cam, you will also most likely not be able to achieve peak engine torque.

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10 months 2 weeks ago - 10 months 2 weeks ago #61370 by alades
I have verified the base timing is correct. I have performed a few things I really don't like doing such as parts swapping by replacing one of the fuel injectors and one of the coil packs with new ones. I have also replaced the PCM and I am still getting the same result of a misfire while not under a load starting at about 1500 rpm and up but it will not idle under a load. I'm about to pull my hair out on this particular one because I've never seen a vehicle misfire while not under a load and not misfire while under a load, as it's usually the opposite. The fuel trim data looks normal on both the old PCM and the new one. From what I've seen during my testing of this vehicle, the only reason it idles fine under a load before being fully warm is because the engine idles at a higher rpm to start with when cold and warming up. The misfire that it's exhibiting is one that almost sounds like water in the fuel. However, from experience, a misfire from water in the fuel is more prevalent while the engine is under a load. The only thing I really haven't done on this vehicle is check all of the grounds. Although the Ford garage said it's the torque converter, myself and other techs disagree with that diagnosis because of the weird misfire when the engine is not under a load at about 1500 rpm and up. Also, the torque converter data is within specs on both the old and new PCM.
Last edit: 10 months 2 weeks ago by alades.

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