I have an 04 6.0 and a couple of months ago I had a rough start issue that when I started the truck in the morning it felt like the motor was about to jump out of the truck finally one morning it just would not start at all so I had it towed to the shop and had a diagnostic test done and he came back with a 2 page list of possibilities and said it was showing low circuit on 6 out of the 8 injectors then he told me a bunch of parts that we should start with then finally end with changing all 8 injectors. Well after looking at my check book and reading lots of posts on this forum and others I talked him into taking a FICM out of another truck that he was working on and sticking it in mine and sure enough it started. In his defense that was on his long list of possibilities anyway I bought a new FICM and also changed the injector harness due to some chafing issues that we found and all was good for about 2 or 3 months (4k miles) now its starting to have some cold start issues again no where near as bad though it fires up pretty good as good as it ever did maybe 2 sec of crank time then it gets a little rough but then it will smooth out for a while then it will get rough again and so on until it warms up then it runs perfect. My mechanic of course is very quick to shout out injectors just like everyone else I just have a hard time believing that it fires up that quickly and runs perfect after warm anyway this morning I lifted the hood to get a better listen when I started it and noticed that my hood light goes on and off in sequence with the way it runs in other words when it runs rough the light gets dim and kinda goes off and on then when it smooths out it is on solid and bright. My question is if it was running rough due to something mechanical would the light do that or does it seem like something electrical like batteries alternator or maybe even a short that gets better when it warms up. Please help!!

 

that sounds like possible Glow Plugs control module, that will cause bad cold starts, and if its bad will cause lights to dim. another possibility is you have bats going bad, did you change them yet? 04 they about to be on their last leg, and this might have been a cause of you FICM going bad too.
if i were you check the GP module and batts.....

 

I bought the truck used but the batteries have a sticker 10/07 but I am sure I put a pretty big strain on them when I had the no start we tried doing things to get it to start for a week and ran them down a couple of times and had to charge them up. Is there a way to tell if its the glow plug module?

 

if it is, you can have it scanned and see if you have any GP codes. im new to 6.0 but i bet there is a way to check them, i know they are going bad and if your glow plugs are not operating normally or not at all you might have hard time getting the truck started in very cold or freezing weather.

 

Just an update, I went to autozone and had them load test the alternator it came back good at 13.9 volts and one battery tested good battery (passenger side) Driver side battery came back good low charge battery. What does that mean I drove 20 miles to get to autozone should it say low charge?

 

Replace BOTH batteries ASAP before they damage the alternator.

 

+1 on what he said ^^^^

You need to get those batteries replaced ASAP. Also when you get them replaced go back and have the alt. rechecked. The truck should be charging around 14.4 volts or so. If the alt. is bad it will destroy your batteries and possibly wipe out the new FICM again.

You could have an issue with the main engine harness also. I believe in 04 there were some chaffing issues with this harness. Hopefully someone with more info on this will chime in.

Good Luck.

Sarge

 

Another little update I was tinkering around again under the hood cleaning the battery terminals and notices that the clamp on the positive side of the driver side battery is over half way missing. I did'nt see it earlier because the red rubber was covering it but when I took it off the top of the clamp was still there but most of the clamp that goes around the battery post is gone and it had alot of corrosion on it. I cleaned it up and put it back on the best I could until I can get out and get a new one tomorrow. Could this be the problem or am I just really wishful thinking. That was the battery that said good battery low charge on the test.

 

Thats a great place to start.

Sarge

 

OK this morning I went to start the truck and I had a really weak buzz, normally when I turn the ignition on and the glow plug light comes on I get a solid buzz for about 5 or 6 sec and then a pphhsstt sound then I start the truck this morning I could'nt really hear the buzz but I heard the pphhsstt I heard either a weak buzz or something running before I tried to start it so I ran to look under the hood to see where it was coming from but it stopped right when I got there but it sounded like something by the passenger side fender they have a little silinoid looking thing right there not sure if that was it or something in that area. Does this make any sense?

 

Can you have it scanned for codes. If your FICM is going bad you will have a code P0611 in it. Those were the same symptoms I had. When the FICM was replaced my injectors now sound like they used too.

The noise you hear from the R/F is probably the vaccum pump running...does it sound like a motor running? If so its the vaccum pump.

Sarge

 

6.0L Tech Here-

the buzz you are hearing is the injectors cycling before you start the truck. sounds like they are getting a little weak. 6.0L are funny like that if something is run out of specs long enough it will want to stay there. My bet is that your FICM was going bad and its great that you replaced it BUT. and this is a big but, when the FICM doesn't fire the injectors properly they tend to get internally damaged. they are made to go off at the right time and dont stand for much more or less then that. so im really sorry to say this but your Ford Tech was right. the injectors do need to be replaced. and im not tanding up for him cause i am one. i do my very best every day to rid the world of hack jobs and hes not one of them. id make the very same recommendation. people figure that if they are getting injectors replaced thay they should upgrade but this just backfires again in the electrical circuit making the FICM intermittant. anyways thats what ive got for ya. hope it works out ok.

 

When my injectors where misfiring due to my FICM I had smoke so bad I could hardly see behind my truck now I have the normal little puff right when I start it just like you see on every truck start. When I go on line and look at video's of trucks with injector issues every one of them smokes horribly, mine does'nt. When my FICM was failing it was obvious that it was not hitting on all cylinders this time its not like that its more like a weak idle that can hardly stay running but not bucking and misfiring like before then after awhile the idle gets stronger and stronger.

 

you know im not sure cause everyone i have had has gone for the new injectors so i couldnt tell ya. you got something new to me on your hands if its not the injectors.

 

replace that cable end, do a voltage drop test on all of the battery cables,check the fluid levels in the batts too, charge the battery and retest. possibly what you heard running was the vaccuum pump, its just behind the passenger battery i believe. i believe in fixing the small cheap things before i reccomend replacing expensive parts. when injectors fail you should be able to see it on a scanner for the first couple minutes on the first start of the day. if it don't code don't waste money. i believe in the scientific method not the throw parts at it method. i just don't understand any tech whether its car,truck, motorcycle, whatever who says i don't have proof but lets change these real expensive parts on your dime and see if it helps, oh by the way you can't return them once the box is open. i really do not like being the techs guinnepig