Coyote stumble on acceleration

[Svtfreak]

In a hot rod. Frpp controls pack Gen 2. CMCV'S disconnected and tied open. Factory mass air meter in place just hanging. No air filter. 4 unused vacuum ports plugged (the evap canister purge point, the empty point in TB that went to the cmcv's, the old sound tube point and the empty vac point on outside of the elbow inlet to TB).

Car starts and idles fine. Get going and does OK and very small throttle inputs. Try to be more aggressive and it starts cutting up. Like at about 1/4 throttle. Almost sounds like running on half-6 of the cylinders. Back off and smooths out. Only got up to 20 mph or so. The check engine light is not on.

Any insight? Ford says its the lack of inlet box and air filter. Could it be? Not sure I have room to attach it to test. I'm also going to double check my plugs in the vac fittings. But quick check says they OK.

[michael everson]

I have found the mass air meter to be very finicky. Put he air cleaner on and see if it improves. Also I found the mass air meter worked best if it was straight up at 12 oclock
Mike

[Rsnake]

Mine did the same thing and ford said it was because of the free flowing exhaust and cai. Had Lund send a tune and now runs perfect.

[Dave Howard]

Tune x2. I'd finish off the car and configure the engine the way you intend to operate it then get the ECU tuned. My preference would be a custom tune from a shop with the car on a chassis dyno.

[lewma]

This may be nothing but did you calibrate the accelerator ? I did a first start last weekend on my coyote and I noticed that the engine would stumble as I was advancing the pedal. I read that the accelerator needed to be calibrated. Basically turn on the ignition then slowly press the pedal all the way to the floor, then back again, then turn off the ignition. Not sure if this will help your case but it definitely cured my problem.

mark

[Svtfreak]

Jimland is going to loan me his spectre intake that works great on his car. He hasn't nixed the cmcv's but IL try it. Just to see. I'm going to get a tune but was hoping to do it once once the blower is on. If I have to twice, we'll so be it. Don't think the big factory air box is gonna fit.

Lewma, I'll try that also. I did accidentally start it once without it plugged in. Maybe that freaked it out. Worth a shot for sure.

[Svtfreak]

It was a combination of things. The intake box missing def had something to do with it. I added the factory box and filter. The other problem was even though it showed. 1/4 tank of gas, it was empty. The pickup is too short. I filled gas and added the box and other than the occasional stumble possible due to still being cold, and not having cmcvs hooked up, runs great. Thanks guys. I never would have thought that would make that much difference.

I taint pretty, but it helped trouble shooting.

Soon, all that is coming off to be replaced with a Whipple belt driven intake.

https://i.imgur.com/AeM54as.jpg