Last week I posted about how my PSD vibrated AND had a slight surge at idle. I have driven a few others since and they just don't do it......sooooo I know it is not just diesel vibrations (the good kind). Talked to a yacht mechanic today and he said it sounds like a fouled injector. How do I know? I have no codes and no lights. I keep the fuel filter changed regularly, and the truck has only 23000 miles on it! I did run it by the dealer for the gas pedal replacement and they said they thought it had to do with that....yea! right!. Anyway, any imput on this would save me from pulling the rest of my hair out.

 

There are two ways that I know of to clean injectors. One takes a little time, the other is quite quick. Both require that you get hold of some Stanadyne Performance Formula. This is readily available at truck stops, or through Diesel Injection Service. The slow fix is to start using it whenever you buy fuel, adding 1 oz per 4 gallons of fuel. That will do it over a few tankfulls. If you're impatient, then remove the fuel filter cap, and fill the fuel bowl with straight Stanadyne. Replace the cap, and let the truck idle for a few minutes. This will "douche" the injectors in a matter of minutes. This procedure was explained to me by two separate diesel mechanics, so it's used in the trade. It's just a lot cheaper when you do it yourself.
Good luck.

 

Hey, thanks Quadzilla. I knew Stanadyne was preferred by most. I'm gonna give it a try and see if it eliminates the problem.

 

I also have a loaping engine problem and loss of power. I had an electrical diagnoistic test run with no problems. I couldn't figure out if it was a bad injector or valves. I noticed unburned fuel at my muffler. Not a good sign. Did the injector cleaner work for you?
Mike

 

Mike, my buddy works for a heavy equipment dealer and brought me hme a couple f bottles of the Stanadyne performance formula. I am meeting him this morning and will let you know if it works. I am going to dump some into the tank first, then if that does not make a difference I am going to do what Quadzilla said and dump a straight shot into the fuel filter bowl. I have me fingers crossed. Also, next week I am going to call a guy I know through a friend at our local diesel injection shop and let him take a look and listen and see what he thinks. However, I will post my results.

 

As long as the injector is functioning electrically, you won't get a code. Also, the problems with injectors that existed on the earlier models (pre 99.5) have not been prevelent on the late models. So, if I were you, I'd attempt to find the offending cylinder (unplug the EBP device on the turbo and start the engine up cold. Have an assistant help you. Hold your fingers on the exhaust ports -- the one that doesn't get hot is the one that is not firing), then check for a broken rocker arm on that cylinder. We had some defective rocker arms on the engine serial number range of 167XXXX.

 

Where, exactly, can one find the engine serial number, Joe?

Thanks.

-David

 

It should be on a stick-on label toward the front of the drivers side valve cover. If that label is gone it will be stamped into the rear oil cooler pad with a matrix stamp (not very easy to read).

 

Thanks, Joe, I'll try it. If there is a defective rocker arm will that cause the injector to act up?.....or better yet, give the type of vibration at idle that I am experiencing? At just off idle RPM's, the engine is smooth with no loss of power.

 

No but if you've got a defective (broken) rocker arm it will cause that cylinder to not be firing which would produce the vibration that you described. Also, if it is a rocker arm that operates the exhaust valve, the fuel that is being injected will be captive in the cylinder and the rings will either "hydroplane" causing the fuel to find its way into the crankcase oil or, worst case scenario, could bend a connecting rod. If it is NOT a defective rocker arm then you may indeed have a bad injector but we've not had much trouble with the post 99.5 injectors.

 

Joe, my serial number is 1944386. It seems like it is well past the s/n's that you were having troubles with. I am going to take a look at the cylinders like you said to see if I have a firing problem, then just attempt to go through a process of elimination. I know the dealer will not take the time to trouble shoot and the only way they are going to fix anything is if there is total failure. I have already started with a tankful mixed with Stanadyne, AND dumping a few ounces straight into the fuel filter bowl. It has not made any difference in the hundred or so miles driven so far, but I guess I have to be patient.

Also, Joe, if there were a broken rocker, would I have a noticeable loss of power? Other than a resonant vibration at idle, power or anything else has not been affected. The truck runs great, it just has that anoying vibration. One stupid thought I had was the exhaust. Could a baffle in the muffler be broke causing a back up? I put my stethescope to it and the only real place I can get a duplicate of the vibration is through the exhaust. It is less as you go from the tail pipe up to the down pipe. Just a crazy idea, I guess, but I am just trying to pinpoint it.

 

You are correct that a broken rocker arm would kill that cylinder through out the RPM range and you'd have a noticable loss of power through out that range. If you are going to pull the valve covers, shine a light down the push rod holes and look for a bent push rod (why you should have a bent push rod is a mystery to me but if the valve covers are off anyway...)
I'd be surprised if the exhaust system is the problem. If there were a restriction it would be giving you a problem at higher RPM under a load.
You may have to take it to Ford for diagnosis. They have a scan tool that runs a cylinder balance test at idle and since that is where your problem is occuring, their scan tool should be able to pick it up. It will tell them if any cylinder is not firing -- it won't tell them why. If the compression on the offending cylinder is OK they'll replace the injector (about $400). If you are under warranty, that is the way to go.

 

Joe, thanks for all your expertise and help. I am going to go ahead and let the Stanadyne work its course and in the mean time I am going to schedule an appt with Ford for some warranty diagnostics.