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Discussion Starter · #1 ·
I have the 6.5 detroit diesel in the truck when I bought this truck on Saturday they seller said to me that the truck runs rough as hell so I thought maybe 2 thing air or fuel .... I started with the air system changed the filter I checked for any blow by or oil in the turbo or anything wrong that I could tell from my experience as a diesel tech I checked the fuel system and even changed the filter and bleed the system. The seller told me that there was the feed the beast mod on it and tbh I don't know what that is but I tired looking it up to see what it was seem to be a fuel upgrade but I haven't heard of this mod so I have 2 issue I see that makes this engine bad atm When you started the truck it takes a lot of turning the key off and on so I don't over crack the starter but if I hold It and keep slamming on the gas it seem to kick but if I hold it all the way down to the floor and it start it runs but when I let off the gas it seem to die out in secs but if you hold it down you keep it up around 1rpm and if you hold it down for 1 min straight it seem to recorrect it self it revs to max once I let go it idles like nothing never happen but I get two codes on it 35 36 or even 34 but I know it around them 3 because I kept repeating it in my head but anyway I noticed when I get it warm up and seem to have the throttle service light on and as well for the service engine soon go on and off fast . But when driving it it all goes away its just a horrible start up and a rough 5-10 mins of trying to get it to idle.
 

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Welcome to DieselPlace
The "Feed the beast mod" is a modification to the fuel filter housing that allows more fuel to flow thru. ( You can read about it in our 6.5L FAQ page)

Start by performing a lift pump test Reference Material: Lift Pump/OPS
Install a piece of clear fuel line on the return side of the Injection Pump to help locate any air in fuel issues, as shown in this link Question: - 1999 GMC Bluebird 6.5L TD - PMD &amp...
 

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You need to get the correct trouble codes. They can only be retrieved with an OBD2 scanner.
1996 Sub in your sig is OBD2. All codes will be more than 2 digits. The 2 digit codes you listed are OBD1. 95 was the last year for OBD1.
OBD2 codes start with a P followed by 4 digits. ex P0123.
There is a sticky at the top of this forum that reads Info: - The 6.5L FAQ's... The Master List of... there is a wealth of info listed in there Including free downloadable shop manuals for your truck. Might want to spend some time there to get familiar on how these engines operate.
Check out the section on grounds. Bad grounds will cause all kinds of issues.
 
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Discussion Starter · #4 ·
Welcome to DieselPlace
The "Feed the beast mod" is a modification to the fuel filter housing that allows more fuel to flow thru. ( You can read about it in our 6.5L FAQ page)

Start by performing a lift pump test Reference Material: Lift Pump/OPS
Install a piece of clear fuel line on the return side of the Injection Pump to help locate any air in fuel issues, as shown in this link Question: - 1999 GMC Bluebird 6.5L TD - PMD &amp...
thank you I will be out there tomorrow doing this I might as well just jump the steps ima buy the ops because the truck has a updated lift pump but ima still try to see if I have the right pressure in the system because again it runs fine after it clears it self up because I can drive it like my other 6.5 with no issue its just when the start up it seems to lose fuel pressure and the acceleration pedal doesn't go to max right off rip its stays very low at 1prm or lower then that I have to hold my foot and keep it there and once I hold it will stay fine when I let go it stay at a very low rpm and but again 5 mins later I hit the gas the pedal just seem to work just fine when I let go the rpm drop when it hit it it goes up it's just something that is simple or it could be something major but yes thank you again I have been reading what you told me to watch!!!
 

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Discussion Starter · #5 ·
sorry I typed the wrong year in the post I just bought this truck on Saturday but its a 1195 chevy suburban with the 6.5 dd in it with the OBD 1 in it
 

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OK. I guess I should have read your post title. LOL.
Anyhow. Make sure you dont have air in fuel and LP is working properly. If all good...
Codes 35 and 36 many times are related to a bad PMD. Bad PMD will cause all kinds of problems ranging from No start. stalling, poor performance, to a full runaway condition.
Is PMD still on the pump or is it relocated? If relocated, the extension harness could be bad.
 
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If you replace OPS, you need to buy ACDelco NOT the part store brand OPS.
 

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Discussion Starter · #8 ·
I only buy acdelco I have an account with rock auto and autozone so I got the truck to run today no stalling but there is the long crack time and a lot of smoke when starting and still no respond from the pedal but once it idle for like 1 min or 2 it will run like nothing happen think maybe there is an issue with the floor pedal or a grounding issue because there a grounding strap on the frame rail by the pass side / starter is located I can't seem to figure out where that goes does it go to the start or to the engine block ca anyone tell me what ground to look for on the frame rail by the starter
also big question I get smoke coming out of my dip stick and oil cap is that a head gasket??
 

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IIRC, From the engine block to the frame.
Anywhere on the frame.
I suspect, there is probably still a bolt there somewhere.
 

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also big question I get smoke coming out of my dip stick and oil cap is that a head gasket??
A head gasket would put compression in the coolant system. Pressure in the crankcase is usually blowby the piston rings. Some, is normal for these engines. A lot or a distinct pulse in crankcase pressure is bad, like broke ring, hole in piston kind of bad.
 

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The flat grounding straps go from the frame rail, by starter, to the firewall and same spot on firewall to rear of passenger side head. Take apart and clean ALL grounds. The 2 main grounds for the ECM and dash are on the rear of the intake manifold.
 
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