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Could you be referring to the air cleaner being removed instead of the intake manifold. Engine can' start or run with intake manifold removed.
If you are talking about the air cleaner, if it is not restricted , we are working toward a fuel and air problem.
Spark is important, but we need to know if full battery power is available to the coils.What kind of test equip do you have to use ?
hi. To confirm. Removing airbox or air filter doesn’t change anything. But removing the actual intake manifold makes it start more consistent and it’ll run for about 10 seconds each time. Obviously I know it’s probably not healthy for the engine to run with it off but it definitely does start/run with it off. Put it back and on and it just cranks. I checked for blockage and didn’t find anything. I have my battery which is new. Hooked up to my diesel truck with jumpers so I can get a consistent crank. It’s definitely air/fuel related. Also the pwm is super high. In the 30-60 m/s range. With the short term fuel trim in the 50-116% range. I’m using a autel mk900 scanner and I have a klein multimeter. A bore scope. I’m a mobile mechanic so I have all the tools. I’ve just never ran into anything like this. I don’t think timing Is off but I haven’t found a good way online to confirm it’s correct without removing the timing cover and redoing which I’d like to avoid. Other then timing the only thing I could think is the pcm is just bad.
The super high short term fuel trim is telling us the PCM has rec'd info from O2 sensors that mixture is lean, agree, if not what do you think ?
I don't like the O2 sensor rdgs in the earlier post.
Did you check if the EGR valve is stuck open ?
As you know when some folks get loose in a vehicle ,anything can be messed up and since you have no idea of what was done , we have to check EVERYTHING.
Could they have removed the timing cover and got loose in there ?
Can you compare the data stream info before starting the engine and then look for what changes after it starts ?
There has to be some drastic change.
Also we have no idea what parts the former owner(s) might have changed and all we can do is look with a fine tooth comb for unusual info from the data stream.
Can't find the CKP and CMP malfunction info, only their removal info.
I found something else as follows:
You said the engine stalls in a few seconds, how about if you give more gas does it last longer? If it doesn't stall that way then you know it's air issue can you clean the iacv, tps the tb? Another same test, but this time you disconnect the MAF connector so that the PCM failsafe values kick in. On iacv fully disassemble it, and have all the new gaskets ready. You know on older cars from the 80s to 90s where there is a screw you can adjust the idle at iacv, of course tps must be disconnected first or pcm will override the adjustment. When that screw is turned clockwise all the way the engine would stall when idle is too low. When the engine doesn't stall then the iacv doesn't do its job and is either defective or must be deep cleaned internally. Cars since the 20s no longer have the iacv adjustment screw, all controlled by pcm but that doesn't mean your iacv needs no cleaning. Same on your electronic throttle body, deep clean it first. Once they are cleaned reset their adaptations, pcm too, reset it or its KAM (keep alive memory). If your car keeps stalling you can't even run most of the diagnostic tests.
I found more diagnostic details on Escape than Tribute. I picked out a few and PDF'd them. If you want to view all download the huge pdf Pinpoint-Tests-ALL below, just that the huge pdf is very difficult to follow.
Here's the index page:
