Hey all...

We've been asked many times for our opinion about miscellaneous engine failures, especially those relating to "windowed" blocks. After reading hundreds of posts on this subject, speaking to dozens of owners and manufacturers, reviewing carnage photos, and comparing countless files from damaged engines, we have a few theories. In fact, we've just finished writing a calibration simulator for the <acronym title="Power Stroke Diesel">PSD</acronym> that helps quickly identify just how significant a role tuning may or may not have had in relation to the failure.



In order to rule out isolated issues and identify any trends, we are conducting an independent survey of all 7.3L Power Stroke engine failures to see if there are any specific commonalities among the failures. The failures in questions will be specifically related to MODIFIED vehicles (i.e. Chips, Injectors, Turbos, HPOPs, etc.) and we would appreciate anyone who has suffered an engine failure of any type to please take a moment to fill out the survey. All NON-PERSONAL data collected will be made available for download to any individuals or companies that are interested.

The survey is located at --> Survey of Power Stroke Engine Failures <--

I do want to take a moment and remind people to please be considerate and use this as an opportunity to get past the old issues and move forward in a positive fashion, NOT as a means of complaining about what damaged the engine. We've all read the posts and heard the arguments, but it really doesn't accomplish anything except getting a lot of tempers flared up. We may not all have to get along, but we are all striving for the same thing... making the Power Stroke a reliable source of performance.



We appreciate everyone taking the time to fill out the survey and hope that it will provide valuable information for all 7.3L Power Stroke Diesel owners and vendors, past, present and future.

 

The survey can be accessed at Engine Failure Survey.

 

Thanks
Clickies for you.

 

Thank you!

 

Just wanted to say a quick to those of you who've taken the time to fill out the questionnaire about engine failures. Your answers have been very informative so far, and I'm happy to report that EVERYONE'S been totally objective with their comments. Your time is very appreciated!

 

Wasn't there a survey like this done not to long ago?

 

I know that Dennis from ITP had one posted on another forum (not sure if it was posted here as well) awhile back, but it's nowhere to be found. If there was another, we don't know about it.

People keep coming to Bill for answers about their windowed blocks, and he thought that posting information without getting all the facts wouldn't be doing anyone any good. Therefore, we created a survey asking for very specific information from drivers who experienced engine failures.

So far, people have been great at providing data to help Bill with his conclusions about the cause(s) of the failures.

 

That is the one that I was thinking of. Thanks for jogging my memory.

 

Good luck with your survey.. What is preventing someone from filling it out with bogus information... Multiple times?

 

There are always ways around security measures (obviously, I won't post about what they are on here ), and if someone wanted to take the time and figure it out, I guess they could do it. Most survey questions are multiple choice, but there are many that allow the driver to provide comments, and most people have chosen to do so -- WITHOUT bashing, mind you. Additionally, we are asking them to provide name, address, phone number, and e-mail (there is a message right above this question that states that it WILL NOT BE SHARED WITH ANY THIRD PARTIES WITHOUT [YOUR] WRITTEN CONSENT). Our hope is that this might ward off anyone who would fill out the survey with a hidden agenda.

The whole survey takes about 20 minutes to fill out (if someone chooses to provide comments). I guess someone could probably take the time to thwart the "system," but we haven't seen anything that would raise any eyebrows -- not to say that it couldn't happen... we just haven't seen anything like that.

It's early, but some trends in the data are definitely evident. One is the injector(s) affected at the time of engine failure, but there are certainly others. A lot of thought and time went into creating this survey, but it looks as if our hard work is going to provide us with much needed information, which is what our intention was all along.

Thanks for the "Good Luck!"

 

Reps to you and Bill for conducting this survey. Looking forward to the results.

My bet is that injector nozzle size and/or injection timing may be at the top of the list of things that are causing failures. I am leaning toward the injection timing. JMHO

 

Thank you so much!

It looks as if you may be right about the injection timing. The screen shot in my OP shows a program that Bill recently wrote that simulates the PCM's calculations for start of injection, injection pulsewidth, and ICP. Using these calculations -- along with flow characteristics for any particular set of injectors -- we can determine what would be ideal start of injection based on a desired end of injection point.

In his own words:

PCM . I got tired of the fact that the PCM doesn't provide any type of SOI values for datalogging so we had to resort to basic math to achieve those values.

There are 4 inputs...

RPM
ICP
EOT
TPS

...which can be manipulated to simulate a number of operating conditions.

Since Desired <acronym title="Injection Control Pressure">ICP</acronym> is actually calculated by the <acronym title="Powertrain Control Module">PCM</acronym> based on RPM and Mass Fuel Desired values, there are two way <acronym title="Injection Control Pressure">ICP</acronym> can be handled - either automatically or manually. The reason we added the manual option was to be able to force a situation where <acronym title="Injection Control Pressure">ICP</acronym> may be less than (or greater than) desired in order to see the subsequent affect that <acronym title="Injection Control Pressure">ICP</acronym> has in relation to the overall outputs.

Aside from the manual inputs, the software is able to run CSV-based scripts to feed inputs into the calibration and then datalog the outputs which can then be exported into a CSV file for further analysis and graphing. With the scripting capability, we can simulate runs at full throttle, light throttle, cold engine, warm engine, high <acronym title="Injection Control Pressure">ICP</acronym>, low <acronym title="Injection Control Pressure">ICP</acronym>, and varying RPM ranges.

All the base fuel and timing functions are covered and at some point we may even include some basic shifting outputs to see just where we can expect shifts to occur at specific throttle values. That's a ways off though. As it is, I've already got more than a month tied up in the software.

We've been able to look at several calibrations that would astound anyone in the tuning industry -- even a novice like me! -- and his results are being backed up by the data in the survey.

Bill's just trying to get the entire picture into focus and not simply look at bits and pieces here and there, which is what we've seen done a lot in the past on the forums.

Thanks for the support!

 

Well reps to you for taking up this important project, nothing like getting to the core of it all, subscribing..

 

Something that I would like to see in the survey is what voltage IDM was in use. 110V, 120V, or modified to 140V. The modified 140v IDM does slightly advance SOI. Maybe it's just not that significant.

 

You are absolutely correct. I completely forgot that one as well. Adding now. We've also added a question about how the vehicle is driven while the engine is cold (< 100º).

Well, so far there have been some interesting results.

One thing we have found QUITE surprising from the failure data was that out of 61 specific failures, 38 of them occurred on cylinders at the front half of the crank with 23 occurring on the rear half. Also, cylinder #2 experienced more individual failures than any other cylinder.

This brings the question... has ANYONE ever checked the crankshaft to see if there was any twist between the rod throws? It's possible that the reason we see more front cylinder failures is that the back half of the crankshaft is a few degrees ahead of the front and is causing the rear cylinders to respond to the combustion differently.

One of the factors we now want to take a very close look at is how the vehicles were started and driven. If you have already filled in the survey and have the time, we would appreciate if you add a quick comment as to how you started and drove the truck, particularly on cold days. Basically, are you a "Start and go" kind of person or are you a "Start and warmup" type? This information would be extremely helpful in further tracking the nature of the failures.

Anyway, we're up to 23 extremely detailed entries and getting more each day. The survey is really providing a lot of insight and is helping to validate some of the theories we've been kicking around recently.

Thanks to all who have participated so far. It is greatly appreciated.