Highway & Heavy Parts Answers Your Diesel Engine Questions: Fuel Injectors


fuel injectors customer questions | Highway & Heavy Parts


This month we're going through the questions you want the answers to. Today's topic: fuel injectors.

Are you having problems starting your truck? Poor idle or poor performance? We get these questions a lot from our customers, and in most cases it usually ends up being a problem with fuel injectors. So we're taking you through the answers to your fuel injector questions!

You can also check out our video for more information:



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Your Diesel Engine Fuel Injector Questions

Do you have questions about diesel engine fuel injectors? We've put together answers to questions that we often see from our customers about their injectors:


cleaning solution for sticking injectors | Highway & Heavy Parts


If I have a sticky injector, is there a solution that I can use to clean it instead of replacing it?

The potential for an injector cleaning solution working is a possibility, however, a lot of times when you get into a situation where you've got a sticky injector, you may have had some water or some debris go through the injector. This causes the insides to be scored or damaged in a way that makes the injector stick.

So,  if you're using some sort of cleaning solution to go through the injectors, there's a pretty small chance that you're injector will be fixed by that. It's more likely that you have some sort of internal debris or something that's causing the injector to stick. It's probable that you'll have to replace that injector.


Are injector trim codes based off firing order?

So, the trim codes are put on each individual injector to give it some sort of fueling offset, to make that injector fire within the window it needs to. This is really in regard to the amount of fuel that it's putting out. 

So, the trim code has nothing to do with the firing order other than you need to know what trim code is on the injector and what hole you put it in, so you can give the ECM the data. That way you know what injectors to adjust and how to adjust them.

Want to know more about trim codes? Check out our article on what trim codes are in diesel engines.


Could the skipping in my ISX or QSX engine be from a bad injector?

Absolutely. That's one of the main reasons you would have a skip or miss in your engine. 

Do you have new injectors for your ISX? Read our post to see how to install your ISX injectors!


troubleshoot ixz qsx fuel injectors | Highway & Heavy Parts


How do you troubleshoot to see what injector is failing in an ISX or QSX engine?

Probably the first thing you do, if you have insight available, is hook insight up to the truck and do cylinder cutouts. A lot of times you may be out on the road, or you may not have the computer available.

In these situations a laser temperature gun can be really helpful for checking out what your exhaust manifold readings are. If you're going across your exhaust manifold, and you notice one that has a temperature way different from the others, then you have a pretty good idea of the one that's off. So the temperature is a great indicator of what's actually coming out of the exhaust and that's due to the injector either firing or not firing. That's just a quick tip for checking you injectors when you don't have a computer on hand to hook it up to. 


If you have any further question on fuel injectors from any major OEM, give us a call or chat with us on our website. We'd be happy to help you out with any questions you may have!


Want to know more about your diesel engine replacement parts options? We have ASE Certified Technicians on staff who can help you out! Give us a call at 844-304-7688, or request a quote online