Dumb question. Have you measured fuel pressure under load?
All great advice. +1
I agree it is ignition or fuel but everything I test comes back clean which is the most annoying part.
Yep, already checked for codes, nothing active, stored or pending.
I looked at the intake valves when I have the intake off, they looked good, other then a little oil/carbon build up everything was in good shape.
Clogged catalytic converter (seen this before) - possible but the scan tool showed the correct temperature in it, I would think it would either be high or low if it was clogged.
Fuel pump or fuel pressure regulator - yes, my next thing to test, I checked the fuel pressure at idle and it was fine, going to test it driving tomorrow.
Fouled spark plugs (I know you cleaned them, but I would change them out for the Motorcraft thin wire double platinum) - yeah, also my next plan is to toss in some new plugs, although the lack of any kind of misfire doesn’t instill hope that this is the issue.
Bad injector (but would have rough idle, hesitation) - It is not a single injector for sure, it runs way too smooth for that, all of them being clogged is possible but no other signs of this being the issue, fuel trims are on point in the ECU.
Vacuum leaks (but you checked-also check evap vacuum lines and egr) - I checked all the vacuum lines, they are good now. Evap was checked. EGR I have only glanced at but saw nothing saying it has an issue and the ECU says it is working fine.
Bad ignition grounds - anything is possible, I checked a few grounds while I was under there and a bit dirty but nothing that concerned me.
Failing ignition coil(s) - I just replaced the coils like 5k miles ago but I do still have the old set (turned out they were ok), I plan to swap those in when swapping the spark plugs to see what happens.
I can only think of 1 time that a car got the better of me, one of my RX7’s was a money pit and finally got to the point I was fed up and put it up for sale and had it sold a few hours later. Broke even on it though lol.
If I could get into the tune on the ECU I am sure I could track the issue down, I always hate working on cars with locked ECU’s.
Not specifically, this was also my thinking since it idles fine (except when coming to a stop it will try to die sometimes) but has issues under load.
It was fine at idle but don’t remember checking under load.
I plan to test this tomorrow.
Thanks for the help everyone, this is the strangest issue I have run across in over 25 years of working on cars. Normally something is wrong and when testing things there are signs that can clue you into where the issue lies.
This car just says everything is great with no clues! lol
We used to duct tape a gauge to the windshield and drive around. Very common for lift pumps to fail this way… check fuel filter too. May be collapsed and clogged.
Yeah, done that before.
In this case it outputs the fuel pressure on the OBD, so it makes it a bit simpler lol.
Ok, just drove around with the ODB scanner and like before everything checks out with what I would expect.
Fuel pressure is good both at idle and while driving.
Only anomaly I found is a rather unhelpful “engine load” and “engine load absolute”
At idle these are sitting at 55% and 30% respectively. If I give it any gas or while driving it basically sits at 90-100%. This is also what it feels like, the transmission constantly downshifts and it just acts like it thinks it is under a high load.
The TPS reads the correct throttle position though, so not sure what is giving it this impression.
Only other thing that stood out was the MAP sensor was reading between 3-14psi depending on throttle position, but I think that is just relative vs absolute values.
Gonna grab some spark plugs later today and try my old set of coils to see what happens, these plugs were new when I got the car and I got the nicer plugs as well. New coils as well so strange they would already have issues if that is the case.
That’s actually not unhelpful. This points to an airflow calculation error, if I’m not mistaken. Could you report MAP values and check units (“Hg vs psi) with engine off, idle @ 0% TP, and at ~1200 rpm?
Before I dive in fully and look it up myself, does this only have MAP, or is there a MAF as well?
Also, when was the last time you’ve done a capacitive discharge/reset the ecm?
Yeah, I said “rather unhelpful” 
I will check the numbers again, nothing stood out when I looked at them before although there are a few different places it is reported.
It is a MAF + MAP setup, was actually not aware of the MAP until I took the manifold off and saw it mounted to the bottom.
I disconnected the battery all day yesterday while working on it, but maybe I need to do the full connect the battery leads together to discharge everything rout? I can try that tonight and leave it overnight.
Here are the values at idle, exactly what I would expect:
Here it is at ~1000-1200rpm:
And here is the load at idle:
I did see my first sign that it might be an ignition issue though, when watching the O2 sensor and holding ~3k rpm, I was getting a stumble / misfire intermitently and the O2 sensors would freak out when it happened leading me to think it was a misfire.
So maybe it is ignition related. I guess I will know in a little while.
Quick experiment proposal…
Pull the intake hose off so that the MAF isn’t in the flow path. Does it still run? How similarly?
Interesting idea, I will give that a try.
The second screenshot shows 0g/s MAF. Was the engine running at that time?
No, the first 2 were with the engine off as a baseline. The next 2 are with the engine running at ~1000-1200rpm
Ok, I pulled the intake pipe and got some interesting results.
First as you would expect, it died and would not even stay running BUT only after about 5-10 seconds.
During those first 5-10 seconds it runs perfectly, obviously it is still int he start up map and not in closed loop yet.
This explains why the first take off after starting it up always feels so good, having the power I expect but the next take off is far far worse ever since I got the car.
The question is, what sensor is throwing things off. Since it runs good during the start up period (had to restart it while rolling a few times to make it around the block), it basically rules out any mechanical issues, timing issues, almost rules out clogged cat etc.
Doesn’t give me hope for spark plugs / coils either as when I restarted it when already rolling it drove basically normal for the next ~5 seconds.
did some more testing, I disconnected the MAF and tried that, interestingly, it ran basically the same as with it connected? Maybe even a little better in some ways.
I also figured out how to do some basic logging with the app and discovered what I think is the root cause of the lack of power, lack of timing.
At the points where it has zero power timing is almost 0, and points where it has a little more power timing is in the 20’s. Although even at 4k WOT Timing stays in the high 20’s. Seems like it should be closer to 40 degrees but could just not be used to this engine.
The short term fuel trim is also pulling a lot of fuel now after disconnecting and reconnecting the MAF.
The butt dyno says it is getting too much fuel and too little timing, which falls in line with the load calculation being way too high.
How do you know what is causing the high load readings?
I have been looking up MAF sensor readings and I am thinking that my numbers are much too high for my little 2.3l.
I am seeing 5.4l ford trucks with lower readings at idle, I am getting about 5-5.5g/sec at ~750rpm idle it looks like.
Hmm, more testing to do, I cleaned it a few months back but can’t hurt to do it again. Also going to double check the idle numbers now that I have something to reference it against.
Edit: Confirmed, once idle settles down I am sitting right about 5g/sec on the MAF, which would seem to be almost double what it should be. Just cleaned it again, it was already super clean so naturally didn’t help.
Also found the open/closed loop output and sure enough confirms my hunch that it runs bad in closed loop and open loop run ok (not great but ok, although pretty sure I fouled the plugs when messing with the MAF, it was running pig rich for a bit).
I found a new old stock OEM MAF sensor on ebay for $20, I made an offer for $15, see what they say. Figure I will rule that out for good and if that doesn’t do it I am out of ideas.
I am open to any ideas on where to look next.
Our Toyota Corolla is a 2006 model, though we got it in 2008.
It still runs great, and our family is frugal so we don't get newish cars very often.
Funny enough the Escape is actually the newest car I have ever had.
My first car was a 2000 toyota 4runner, I still have it to this day in the driveway and was driving it up until we got the ford.
I hit a dip in the road one night going 35mph and went fully airborne! Seems my 20 year old bushings could not handle the sudden shock and I blew out most of them. So it has been down needing those replaced along with struts and possibly shocks. Although for some reason at least one of my rear brakes is also locked up, so got to figure that out as well.
It was actually cheaper to get this escape then it was to fix the 4runner, hence why I did it lol. Plus the ford gets better MPG which is nice.
I have had ~20 other cars but they were mostly fun 90’s cars I would build and tune and then eventually sell to pay for the next project. Had a lot of RX7’s, 300zx, MR2, supra etc. Still miss that 300zx, it was MINT, same for one of my black on black RX7’s.
After several years of that I ended up coming out of it with a profit and a lot of fun under my belt :innocent:
MAF is looking pretty suspect at the moment. I’m curious if you can rotate the MAF 90 or 180 degrees to disturb the flow and get lower readings at idle. (load and g/s)