Hey guys, I have searched quite a bit but have not found much in the way of diagnostic info for a low power situation without other symptoms.

If there is a 'checklist' of things to consider that someone knows of, please direct me there.

My engine starts well, runs smoothly and I generally have no complaints, but she doesn't seem to have the power it once had. It is noticeable when towing heavy.

I have a newer lift pump, have replaced the fuel filter and air filter, and have fixed up some shoddy piping on the pressure side of the intake. I have added a boost guage and it reads up to 30psi under heavy load, which from what I've read is normal...so I figure I'm looking for a fuel related issue.

My next step is to get a rail pressure guage and see if I'm getting good pressure. I'm also considering doing a valve adjustment...to my knowledge it's never been done.

Any other suggestions on where to look for my missing hp???


Thanks,

Chay

 

I should have mentioned it's a 2003 Dually, by the vin it's a HO. There is no check engine light on. It doesn't smoke, except for a bit of blue at low temps (Under freezing).

There is very little (Near 0) blowby. Truck has about 270k on it, unknown history prior to about 170k.

I was reading trying to figure out if there was a way to diagnose injector spray pattern issues without pulling them and sending them off. I guess the answer is no.

Chay

 

Try a heavy dose (32oz) of Power Service Diesel Klean (gray bottle) and drive it like you stole it to see if it clears up. And definitely adjust the valves.

But at 270k miles and possibly with the original injectors they're probably tired and worn and in need of replacing in the not to distant future.

 

For sure. It's 270km, not miles, but still not new by any means. I did do a cycle of injector treatment right in the filter housing. Sea Foam...it was recommended by somebody. It seemed to smooth the truck out a bit, but no power gains really.

I wish there was a way to check the injector without pulling them and sending them away.

I'm used to gasoline injectors which you can check yourself. I could cycle 100% injector cleaner throught them easily, with a diy setup. This 5000psi thing is hard to manage!!

Chay

 

Finally getting back to this issue. I adjusted the valves but there were all withing spec for sure. Just tweaked them and extra couple of thou as I was there anyway.

BTW for me a barring gear was not necessary, just a 15mm socket on a 3/8 ratchet with a bit longer handle, and go slow so the compression bleeds as you go. Also marked TDC and 180* out so that it's easy to get the right spot looking at it from below.

So, next for me is a rail pressure guage and also check to make sure the exhaust isn't sooted up by my BD exhaust brake. The turbo spools fine so I'm pretty sure it's ok, but I'd hate to be wrong and chasing ghosts in the fuel system.

Any further ideas are welcome. If the rail pressure and exhaust check out, then I think I'll send the injectors for a cleaning, or figure out how to do it myself.


Chay

 

After fighting with my ipm-pdc circuit board and winning (lights work again!) i have my power fully restored. I did clean the battery posts well before returning the clamps. Not sure which did it but the truck has more pep than it has in years. Thought id post for others that its a possible source of issues

Chay