Cat 3126 2004 in pete 330 fuel injectors help

supertom · Jan 16, 2010

does any body out there have experience in changing out fuel injectors in cat 3126 2004 version? recently truck wouldnt start checked diagnostics gave code 39, whick is injection actuation pressure fault,i assume becuse i got it started it ran fine for 4 hours that it cant be the pump so im assuming its the injectors,my question is how do you find out which ones are bad and how much trouble is it to change,cause i want to do it myself ,and like to know if anybody out there has a diagram of the fuel injectors and what it takes to find out how to test and find out which ones it is ,cause for the price i would hate to change all out.
and are these rebuildable or can they be unclogged if they are clogged? thanks would appreciate any advise i could get,

bluejaybee · Jan 16, 2010

Here is a whole thread on your subject. It includes the mistake I made by doing what you want to do. Some good info and advise in it.

http://www.expeditersonline.com/forum/truck-talk/34800-leaking-injectors.html

I wouldn't think you would be equipped to rebuild your injectors or even test them as they are electronic. And a word of warning here, there are good rebuilders and there are bad ones. Alot of rebuilt injectors you see advertised are used injectors that passed the test. They are sold as "rebuilt" rather than "tested as good".

greg334 · Jan 17, 2010

His problem is the IAC or the IAC sensor/wiring - not really the injectors themselves. I would start with checking the oil and making sure it is up to the right level - it needs oil to operate.

There are a lot of places to get the info about 39 code on the Internet but I would call Cat tomorrow and talk to a tech about what to look for before you move the truck into a bay. It may be a simple issue where the sensor is bad or the wiring may be needed a splice.

supertom · Jan 17, 2010

greg334 said:
His problem is the IAC or the IAC sensor/wiring - not really the injectors themselves. I would start with checking the oil and making sure it is up to the right level - it needs oil to operate.

There are a lot of places to get the info about 39 code on the Internet but I would call Cat tomorrow and talk to a tech about what to look for before you move the truck into a bay. It may be a simple issue where the sensor is bad or the wiring may be needed a splice.

thanks for all the good advise i will call cat tommorrow ,at least you gave me a good starting point ,if that dont work it will have to go to the dealer see what they can do ,yea and i know bring money! thanks guys!

Deville · Oct 4, 2010

Any new info on this? Did u reslove ur prolbem?

supertom · Oct 5, 2010

Well the problem ended up being a sensor on top of the front left of the engine head . wasn't sending the signal back to the ecm
soory I forgot the name of the sensor it was not the actuation valve sensor. when the sensor is discconected it reverts back to factory default settings so you can still drive the truck,I removed almost every sensor to test except this one .

Deville · Oct 5, 2010

supertom said:
Well the problem ended up being a sensor on top of the front left of the engine head . wasn't sending the signal back to the ecm
soory I forgot the name of the sensor it was not the actuation valve sensor. when the sensor is discconected it reverts back to factory default settings so you can still drive the truck,I removed almost every sensor to test except this one .

Did it look like this?