I recently replaced the head gaskets. The trucks runs great except for it being rough on idle and a ticking noise coming from the drivers side fuel rail (checked the valve covers and head and I don't hear it). When I push on the accelerator it runs fine. The idle rpm's are right between 500 and 10000. The vacuum line going to the rail on that side has suction and all the injectors are seated with new o-rings, and the connectors are on them all the way.

What could be the cause? How can I go about trouble shooting this?

 

Are you sure you're not hearing the normal clicking of the injectors opening and closing? Clean the MAF and see if that helps the idle. If it hasn't been cleaned, I would also clean the throttle body.

 

Why did you start a new thread?

https://www.f150online.com/forums/v8...-question.html

 

Isn't it just the ticking of the injectors?

 

glc - made a new post since this is the subject that is troubling my truck and because I am under a time constraint to figure this out before I have a kinda long drive.

Bluejay & Halverso_99 - I thought it was the normal sound of the injectors but I don't remember them being that loud and the line on the drivers side is louder than the other side, and there is also the rough idle. Because of these 2 issues I'm thinking there is a problem with something connected to the drivers side rail. My next move , if I cant find someone who has experienced this problem, is to start switching out the injectors with the other side.

 

Well I disconnected each injector and there was no change in vehicle idle. I also disconnected a plug wire at the coil and the vehicle ran the same. Should the idle get worse when I do these things? I did notice the idle with everything on was close to 500rpm's this seems a little low to me. Am I looking at an ignition problem? Or could an injector still be the problem and since its not running correctly then me removing an injector wire plug from one or disconnecting a plug wire would have no effect?

 

The ticking is normal and it's the injectors IF you've determined and pin-pointed the noise within or from the fuel rail. Yea they get loud, some louder than others. It could be just one, who knows.

It's not hurting anything, but you can change them out if you want. Keep in mind, -even new ones will tick like that. How loud would have to be determined.

Careful, -with all the disconnecting and reconnecting going on, you could do more damage than good. It's definitely not good for it. Just keep that in mind.

 

jbrew - Thanks for the info. I don't plan on removing anything else until I have some solid info and what could be the cause of rough idle.

When I removed the plug wire from the coil while the truck was running shouldn't I have notice a difference in the idle, and miss or something of that nature? Could my crank position sensor have gotten messed up when I removed the timing cover?

My main issue right now that I have right now is the rough idle. It seems fine when I bring the rpm's to 1000 but at idle the truck shakes, which it didn't do before I changed the head gaskets. There are no trouble codes coming up just the rough idle.

 

How long did it sit during the HG job? Injectors may have gummed up. I would run some techron through the fuel system just for good measure. Idle at 500 is way too low.. I would start with the easy, remove and clean the IAC valve. You do the HG repair?

Yes, the idle should have bumped when cutting a good cylinder. Not as much as you would think though. If the truck is only idling at 500 and is rough, you would probably not even notice a difference.