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Dead Burb...

A

Acesneights1

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Northeast CT
Drove about 40 miles, all hwy , to a horrible truck pull. Then went to a place to get boots. Pulled in the parking lot and the truck was idling funny like cutting out. I raced it up and it seems to clear a little. I noticed the speedo was bouncing around a little while it was idling weird. I shut it off and it hesistated to shut off. Went in and got my boots. Came out crank but no start. Opened the bleeder on the FF and it had residual pressue(I was bymyself). No test light but with key on took wire off IP a few times and saw it sparking like it was getting power. Went back in with foot to floor and it finally started as the POS interstate batteries nearly died(Those gotta go).
No smoke that I could see, was still idling bad and had to kepp it raced up a little to keep it smooth. Drove 40 miles home with no problems, plenty of power and it's running fine now. I'm at a loss here. Maybe I should have went to church with it again. I think this thing may see the torch yet. I'm losing patience quickly. Grounds are clean cause I cleaned everyhting up when I had the heads off a few weeks ago. All I can think of is ign switch, LP or IP. When it was idling rough it felt like someone was cutting power to the IP quuickly. Is the IP power looped through the ecm in this thing or come directly from the key ?
Followup:
I tried to start it a little while later and no start. I ran a jumper from Batt to the IP ESO. Still no start until I cranked the heck out of it with my foot to the floor and it finally came to life but was acting like it had run out of fuel, was idling a littel rough and then cleared up Shut it off, started back up . No fuel leaks along the chassis. Either the Mech LP is going or the IP I got is junk.:mad2:
I'm going to grab a LP from Auto APrts tommorow, stock replacement for 93 6.5TD. If that doesn't do it I guess the IP is coming back off.
 
Head and rotor are probably too loose,try cold water on the pump next time,but not while its running or it could seize,. With my one pump I used to carry a gallon of water with me in case I stalled while it was hot,a good douse of water and it would start again.
 
That's to bad,hopefully they will stand good for it,you can't beat a new head and rotor,the fit has to be perfect. I had one shut off solenoid that would intermitantly shut off,but that is rare.
 
Well, I think I know what the problem is hopefully. So after all is said and done and I was ready to rip the IP out ... The truck is running like total crap banging knocking has a low rpm miss. I installed a New LP from a 6.5TD. No difference. In fact, almost seemed worse. I put a volt meter on the ip ESO and gounded to the IP itself and it read 13.8 consistently even when I revved it up a bit and it was making so much noise I thought it was coming apart. It sounded so bad I actually was thinking some sort of catatrphic failure was taking place. Then I took a minute and thought about it. The high idle has some sort of problem. It's always on so I had unplugged it and it didn't bother me enough to figure out why. I'm not excatly sure what the other wire does that goes to the side of the IP and it tied to the high dile but I think it's some sort of cold advance. I thought , wait if the power is constant to the high idle sol then it must be constant to that too so I unplugged it. Now maybe it's a coincidence cause it's raining and getting dark and I didn't have a chance to hook it back up, but as soon as I unplugged it truck ran much better. All the horrible noise was gone. I drove it around the block and was fine although it seemed to have a little less power but when I drove it home on Sat after it started acting up I noticed it felt weird almost like a gas engine running too lean. So if there is a problem causing constant power to this thing when it shouldn't I'm assuming it has a sensor ?? The truck has an ALDL connector but the pin that you would jump for engine codes is missing and I was told that in this truck all the ALDL is for is the ABS brakes. So what's next ? What does that green wire do on the side of the IP ? would that cause this ?
I'm lost now.
 
Also when I installed the 6.5 LP the only fitting I could get locally were Fuel line repair kits so I figured screw it I'll splice right into the steel and make it look all factory instead of hack with rubber lines.
These pics are the right way to add a LP.
 

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The Pump has an electric "Cold case pressure advance" This is connected to the high idle solenoid.

Running the advance after its warm will make it Rattle a lot.

Try dumping a gallon of 30wt oil in the fuel (mix with a gallon of diesel the dump it in)

This will sort out if there is a head/rortor issue. If it runs far better then the IP has too much clearance.


Missy
 
OK but what I am thinking is should this thing be staying on "electrically". When I unplugged it the truck ran fine. If I plug both green wires in the truck high idles even when warm. Something is keeping power to the high idle. where is the sensor to it ? I'm wondering if it's shorted.
 
the sensor is in the right head at the back.

EDIT:it may not be 'shorted' so much as gunked up. the connector on mine was full of oil/slude from a valve cover leak. needless to say it worked better after it was cleaned
 
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given the mess they made of the fuel pump/filter it wouldn't surprise me if the mucked up the wiring for it. I think the power supply doubles with the fuel heater. It's an on/off switch only, nothing in between.
 
Make sure the fuel heater is not on,last thing you need is hot fuel going into a worn injector pump,the injector pump is already to much of a heater.
 
So today I tried again. It was dying driving up the street like it was running out of fuel. I sight glassed the fuel line going INTO the FFM and at idle it looks fine but under high rpms I see bubbles. I'm wondering if the pickup tube is shot. Also the truck is back to not shutting off. I'm ready to just junk it. That is obviously where it was destined to go. what a POS this thing is. I give up. I'm gonna pull the plates cause I'm outta ideas.
 
Did you check the fuel hose at the tank? Also you could blow compressed air back through the line to check if its clogged,you should also do this to the return line,just remember to loosen the cap first. Does it surge alot and rev up and down on is own and then shut off ? Also with the key on,plug and unplug the shut off solenoid,you should hear a healthy click sound. You only need one wire to make this engine run and it should come straight from the switch. If it was mine I would get rid of anything I don't need ,like the factory fuel filter and heater,and run that spin on filter that's on the firewall,the simpler your fuel system the easier it is to diagnose,and you really should have at least a temporary pressure gauge. Suburbans are pretty long are you sure the pump is close enough to the tank ?
 
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do the fuel line leak test. that'll tell aleast if it's leaking. do you still have the mechanical pump on it? as for the glow plugs it's got the newer style controller?
 
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