Low power and low idle

1

12valvetater

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Nov 4, 2009
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Ever since I got my truck back from the shop after blowing the turbo it's seemed like it had a slightly lower idle speed than normal. It also felt like it had less power than I was expecting it to. I went from 181 delivery valves to 035s when the charger blew, so I don't really know what the power difference was between them. I put a bd killer b on it to replace the hx 40 that blew up, and it really didn't feel like it had much if any of a power difference which I thought was strange. Now today the idle was down around 350 to 400 rpm it is really low on power it doesn't get as hot as under load as what it had been and under no load it breaks up and smokes blue and it sounds like it has a miss. The fuel pressure is good like it normally is between 42 and 48 lbs. Oil pressure is good the coolant isn't getting hot and it doesn't have any more blown than typical. Somebody please give me an idea of what is going on. Is it injection pump related or could I have burnt a piston?
 
First off easiest things to do is to rule any internal engine issues. Compression test and most notable a leak down test. This will give you a good foundation to start from.

Low power can be caused by timing, fuel shutoff not engaged up all the way and a few other but this will get you started.

Idle should be around 800.
 
The fuel shutoff is on a pull cable and I checked, it seems like it's fully against the stop. As far as timing goes could that cause the blue smoke while it's breaking up?
 
Yes very much so. Easiest thing there to do is to check base timing.

Pin the engine and pin the p/pump. Now if it's been advanced some you probably won't get the go/no go pin in, however the timing pin should be in the window.

Only accurate way to tell is with a dial indicator in MM increments.
 
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Thank you sir. The smoke has always seemed a little more grey than typically what I was used to. I always attributed it to the lower than stock compression, but it has always seemed to run pretty well. After I put the new delivery valves in its seemed like the idle has been dropping off. Will delivery valves effect timing that much?
 
All things being equal no it should not.

Start with the basics and press from there.
 
I would look back at the DV's you swapped in since that's the only fuel related thing you changed. Other then that Rob covered it!
 
try cracking the fuel lines at the injector. ive had lines get airbound a few times and refuse to clear themselves. its an easy thing to rule out by listening for idle drop and rise when you open and close the nut.
 
That makes sense because the truck didn't seem to like the Rs as much after them. I haven't gotten a chance to mess with it at all, but this is my early week at work so hopefully I'll get to it soon.
 
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