Try removing the ottomind chip and see if engine still has issues.

The chip may have gone bad, or is not seated correctly. Sometimes they can work loose.

Cleaning the contacts can help too.

Then I would check to make sure alternator and battery is good. If alternator can't put out enough volts the fuel pump will suffer, causing low fuel pressure at high load during closed loop to open loop transition.

The chip is my last resort though..I can't think of anything else.

 

As mentioned, the fuel pressure even at the highest RPM is still 40PSI. There is a volt meter guage and it has never shown any drop in voltage.
Early on I removed the chip and cleaned the contacts. No help. After getting the scanner I removed the chip and test drove it. Still bad. Might have been a little worse, but really could not tell.

 

I took a test drive to record the engine timing advance.
at idle about 30
drive,50-60MPH 20-25
accel 10" 15-17
accel 5" 12-15 engine shaking.
4000+ RPM 20

I see no relationship to how the engine is running, only it's RPM

With about 10 gal. gas in the tank, I added 10 gal. of Premium
It ran better, not good, less shake under most problem conditions.

Thinking there may be carbon build-up.

Any suggestions on what to use?

 

totally unsuccessful at finding any engine problems, so, while continuing search,
went on with other maintenance. The transmission was overdue for a fluid change,
I normally changed the fluid in the pan(less than 1/4 the total). Saw about a
fluid flush. Decided to do that. Torque converter has a drain plug. So I drained it.
Used Dextron III/Mercon fluid. No filter change.

SUPRISE!!!!
When doing the drive to adjust the fluid level after the flush, the severity
of the problem was substantially less. Now more of a shudder than an outright banging.
The fluid change is the only item that has had any effect on the problem.
Might be a transmission, not an engine issue.

Searching for transmission problems, I found the following:

Complaint:
E4OD/4R100 Torque converter shudder, feels like running over washboard

Cause:
Several things can be the cause here, one simply being the fluid is
deteriorated badly and a fluid and filter change may remedy the problem.(lessened but not eliminated)
Second is the converter clutch is glazed, damaged or other issue in the torque converter.
Third is that the bushings in the transmission are worn and causing leakage in the converter ckt.
if changing the fluid does not remedy the problem and there's some mileage on the vehicle we recommend rebuilding the whole unit with good reman converter to rule out any issues. On the Diesel and V-10 engines its highly recommended to use a converter with Billet front cover to prevent warpage and HD clutch.

Cooler flushing:
If you have a 1998 and
newer truck with an auxiliary cooler like
the one pictured to the right and your
rebuilding or replacing the transmission
you must replace the cooler with new from
Ford or aftermarket replacement. this will
not flush debris out with using machine
due to its internal construction. reuse can
result in debris getting back into your new
transmission from this cooler.

Where can I get a post/thread for help on the transmission and get
Mark Kovalsky's take on this?

 

I'll tag him: @Mark Kovalsky

 

Changing the fluid in the pan will change about half of the total. Dex/Merc is the wrong fluid. I recommend changing it again, but use MERCON V and this method: https://www.ford-trucks.com/articles...-transmission/

MERCON V has anti-shudder properties that Dex/Merc does not.

 

I have a recently new symptom with my van that I now wonder if it is shudder.
Mostly noticed at speeds under about 40, if I am lightly accelerating or holding steady it does feel a bit like washboard. Very fine washboard; I would say.

I was afraid it was maybe maybe a spark plug/coil/boot...

 

It usually is low grade misfire.

 

with the severity of the problem that I have, is there any advantage to using synthetic?
How often do you recommend a fluid flush in a 34' class A motorhome towing a car?
I also see reference to short and deep filters. Do I have to wait till I pull the filter for comparison to see which I have?
It will be about a week before I can take it out of storage and do this.

 

Synthetic is better for every application.

Flush the fluid every 30,000 miles.

You have a deep filter.

 

is mercon LV acceptable? such as in
valvoline MaxLife full synthetic.

 

If it says both MERCON V and MERCON LV, it's probably OK. If it only says MERCON LV, it will destroy your transmission.

 

Thanks, severl synthetics I looked at list mercon LV.
Seems to limit my choices.

 

I think it will be fine as long as it also lists MERCON V.

 

Here is the link to Valvoline maxlife ATF

http://content.valvoline.com/pdf/maxlife_atf.pdf

It appears that it is compatible with both Mercon V and Mercon LV as well as older Mercon formulation (unless I am missing something )

Product Information - MAXLIFE™ Multi-Vehicle ATF

A PRODUCT OF VALVOLINE TM INC. Suitable for use in:

 Allison TES 389*, C-4
 Audi/VW G-055-025-A2, G-052-162-A1/A2, G-052-990-
A2, G-055-005-A2, G-055-162-A6, G-055-540-A2, G-060-
162-A2, G-052-025-A2, G-052-162-A1
 BMW LT71141, LA2634, M-1375.4, ATF 3.0, 7045E, ETL
8072B
 Chrysler Diamond SP-III, NAG-1, 3403 M115
 Ford MERCONŽ* (in California use Valvoline Dex/Merc)
 Ford MERCONŽ V*, FNR5*, XT-9-AMMF5*, (in California
use Valvoline MERCON V)
 Ford MERCONŽ SP*
 MERCONŽ LV
 GM 9986195
 GM DEXRONŽ II, III