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Chadsix
March 29th, 2012, 04:19 AM
I know i can check injector balance rates through the pid section. But can you do a cylinder cut out on this software? If so how do i go about it? Thanks for any help

noff
March 29th, 2012, 04:41 AM
are u asking if u can shut off each injector, if thats what ur asking they dont have it yet that i know of, hopefully later on though

Chadsix
March 30th, 2012, 02:15 PM
Yes... If it would do a cylinder cut out test. Hopefully that will come in time. Cylinder balance is good too,can tell you alot by if an injector is trimming fuel back to keep balance or or adding fuel. So its better than guessing or pulling them out and having them tested. Ill live

skneeland
March 30th, 2012, 03:02 PM
Yes... If it would do a cylinder cut out test. Hopefully that will come in time. Cylinder balance is good too,can tell you alot by if an injector is trimming fuel back to keep balance or or adding fuel. So its better than guessing or pulling them out and having them tested. Ill live

you can also check each exhaust port with a heat gun, and/or check the resistance across each injector

DoghouseDiesel
March 30th, 2012, 03:02 PM
This is something that we've brought up before and is on the wish list.

The injector kill test is THE easiest way to find the one giving you a problem.

The problem with checking the resistance across the injectors is it only tells you if the solenoid is bad. Most injector issues that we see are cracked bodies / nozzles. Hitting them with the heat gun is "ok", but the cast iron manifolds are so thick and spread the heat that you don't always see much of a variance at idle, unless the cylinder is just dead.

LReiff
March 30th, 2012, 04:09 PM
In my experience a cylinder cut out test will only show a fuel delivery imbalance. Cracked injector bodies and high return rate can only be diagnosed by mechanically isolating an injector.

Chadsix
March 31st, 2012, 01:32 AM
Im not having an issue i was just curious. Like dog house said resistance is Only going to give you the electrical side of things. If you have a cracked body or nozzle or one returning too much to the tank than a contribution test may be in order but most issues can be found with a cut out test.

DoghouseDiesel
March 31st, 2012, 03:21 AM
Doing a kill test shows a lot more than delivery imbalance. If the truck skips, pops, burps, farts, whatever, killing each one will weed it out. Killing a good injector makes the truck stumble and the ECM reacts. Killing a bad one either causes no change in the running condition OR the issue stops.

It's a lot faster to do a kill test before pulling injectors. Takes 5 minutes to do and normally keeps you from running a wild goose chase.

Doing the Cylinder Contribution Test is what shows the delivery imbalance.

skneeland
March 31st, 2012, 03:30 AM
dont get me wrong, i wish we could do a kill test. I was just giving him some other options to troubleshoot in the meantime

Chadsix
March 31st, 2012, 03:39 AM
Again, im not having any injector issues. it would def be nice to do a cut out test when having issues than having the dealer do it. 05 ecm's still had the data link to connect through cummins insight. but 06 they changed the communication and eliminated the data link so insight can only be hooked to the ecm through a breakout harness. wich i tried once and it still didnt work. Sad i run a service dept and we are a cummins dealer and i cant diag my own truck with cummins software... dodge had that one figured out lol. Nope besides my shotty tuning trucks running fine. I do have the tools to cap the rail and isolate injectors thats more or less to check leak down. hopefully it will come soon.

DoghouseDiesel
March 31st, 2012, 03:49 AM
dont get me wrong, i wish we could do a kill test. I was just giving him some other options to troubleshoot in the meantime

Oh, I know. He had just asked about doing it.

His idle issue isn't an injector issue, it's just the values being used.

If all was fine until you made changes to the tune, then ya kinda know where the problem is.

More than likely he did what a lot of folks do and just made a blanket change to values and it's got the idle values spaced too far apart and is causing the lope. That's almost always one value way too high and one way too low and when the ECM tries to compensate, it over shoots and under shoots the needed values, i.e. the lope.

Chadsix
March 31st, 2012, 04:25 AM
Well that statement pinned it on the nose haha. yes my issue is the guy behind this keyboard. your right i did smooth the table as a hole wile keeping my limit values in tact. im working on that right now