Well, I searched about every post I can find to fix my two problems and I’m lost. Both seemed to appear after I changed my oil, filter, fuel filter and air filter. The first part is that the engine is extremely loud now and doesn’t seem to warm up and quiet down until you’ve driven it 30 minutes or more. The engine is louder now after 1 hour of running than it was at cold startup before I did the maintenance. The other problem is loss of power at about 2500rpm when WOT. The truck runs very strong up to about that and then it just won’t go much over 2500 rpm and the truck feels like it’s a got a throttle limiter. So far, I’ve followed other posts and built a boost tester and sprayed the boots down with soapy water. No leaks detected unless I did something wrong. I pulled the red hose off the wastegate and drove it WOT with no change. I guess I’ll check the fuel bowl later to see if I’m getting enough fuel pressure and post a pic of the flow. Thanks for any help.

Matt

 

When you changed the fuel filter how was the bowl? Did you fill it back up without starting the engine? I'm thinking air in the system?

 

Not being a smart azz, but you did use 15qts of oil, right? If so which I am betting is the case then I agree with Jim, check the fuel bowl.

 

Matt -Dumb ? but what brand & weight of oil did you use?

 

I actually pulled the cap first then I drained it and replaced the filter. I then put the cap on and cycled the key three times. How do I purge air from the system?

I took a pic of the fuel coming into the bowl. Doesn't look clogged to me. I

 

Brandon & Bill - I put in 15 qrts Rotella-T 15w40 and it's at the upper mark on the dipstick so no problem there.

 

If there is air in the sysyem it will eventually purge itself out. How many miles have you driven since then?
Did you do anything else while under the hood?

 

I replaced the glow plug relay but it looked identical to the dead one other than it was oriented a little different.

I just test drove the truck with my heavy duty trailer hooked up and at 3/4 throttle there's no problem. Mash it alittle more and it's wasted. More turbo and rev but no more power.

Jim - I been almost 1000 miles since I changed the filter.

 

Matt any smoke, white or black, during this? Have you tried plugging the block heater in to see if that makes a difference?

Dumb question...is the air filter clean?

 

Matt, are you saying when you go WOT, you start climbing more RPM but not going faster????. If that is what's happening, you may have a transmission problem. I don't have enough systems to make sense of this yet.

Do you have more mods then what is in your sig?

 

No. I haven't messed with the block heater as it's not been below 30F here. There is no smoke at startup anymore since I fixed the GPR. The Fuel Filter is new. I'll plug in the block heater tonight and see what it does in the morning. Tomorrow I'll get a new filter, Mobil 1 synthetic and do a change out. See if that helps the truck as I know it won't help my wallet. I can deal with the lack of power for now but I can't tolerate hearing my engine sounding like it's flying apart. Thanks for the help and any more suggestions will appreciated.

 

Matt how old is the oil? When you changed it did you use something different than what you normally use?

 

I'm wondering this too. Different oils have different characteristics with some trucks.

I like your picture of the fuel bowl while the pump is turned on. Maybe I'm just picky, but I don't like any fuel entering the bowl without the filter in place. Remember that whatever specs of dirt or debris that happen to be in there now have a possibility of going straight to your injectors since there was unfiltered fuel floating around in the bowl when you stuck the filter in.

Since you mentioned changing to a synthetic, that makes me think you may have had a synthetic oil in there before the Rotella. If that's the case, then you may not have any problems other than the increased noise.

 

The previous owner said he used the same (Rotella-T 15w40). I bought the truck in September, changed all the fluids, begain having the loud noise afterward.. maybe the "Cackle" is what its referred to but its MUCH louder now. Wouldn't I smell clutch plate if it was my transmission slipping plus is doesn't seem to "slip" until it hits about 2500 rpm.

Rick - the only mod on the truck is a chip that the previous owner had put in by the Ford dealership. I don't know what it is.

 

It makes me wonder if he used Synthetic. With you using dino that would make a difference.

Chris brought up a good point, When you filled the fuel bowl with the filter out, did you drain it then out the filter in, then refill it?

Can you hook up a temp fuel pressure guage to monitor the fuel pressure as you drive. I'm starting to wonder about a weak fuel pump. 1K miles is more than enough to bleed any air out of the system.