• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

1996 Chevy C3500 NO POWER and Codes

Here are some pics off my scanner of what I am seeing........... The timing desired and actual sounds like it is doing nothing the actual never changes at any RPM and the misses are instant if I clear codes it goes to 2 and 8 instantly. I dont think the optical sensor is working at all and should it be like that or should it be intermittent seems like there is no connection to it ( if that makes sense )
Here are the pics

trkcd.jpgtrkcrdee.jpg
 
That 8 count is your 251 code....I'm still thinking about your actual and desired....been a while since I've had to mess with it much......

I'm guessing your scanner doesn't display both the high and low res timing signal missed counts. That would help if it did. If the high and low res signal are out you're pretty much hooped for an OS.

A meter that reads freq would further the diagnosis.

Did you check for air bubbles yet?
 
It just quits after 8 and throws the code.............. and it is instant.
is the actual timing reading zero because the optical is not reading anything........ I just want to make sure I dont have some bad wiring somewhere and it is acting like it isnt there at all. So do they usually just go out period and not work at all or will you get a few misses here and there and finally it will throw a code?
 
troe3696 said:
It just quits after 8 and throws the code.............. and it is instant.
is the actual timing reading zero because the optical is not reading anything........ I just want to make sure I dont have some bad wiring somewhere and it is acting like it isnt there at all. So do they usually just go out period and not work at all or will you get a few misses here and there and finally it will throw a code?
Click to expand...

So it's stalling?

it can run a couple different ways: my 98 would kick and buck and then die. A restart would run a little bit and then kick buck and die again. An 8 count would kill it. That's the low res signal. I can't remember how many counts it took on the high res. The high res is a 356 total count or something around that number (can't recall exactly), it takes quite a few to throw a code. The low res is an 8 count, so it's saying the OS is not seeing any of the disc "windows".

Did you say you had the OS filter harness on your truck? Is it removed now? They are a known area for troubles with open circuits. The filter was incorporated into the PCM on OBDII truck so it's not required and is just another point of failure waiting to happen....
 
No the truck is just hard starting after it starts it runs well just has NO Power I mean 50 mph in the quarter mile with it floor boarded maybe........ It doesnt sound bad doesnt smoke it doesnt do anything wrong besides have no power and hard to start........... I did remove the filter inline to the OS no change at all. I might take the upper plenum back off and go through the wiring one more time before I order a new pump. Any words of wisdom on buying a new pump?
 
if you want a good pump try to verify it has a new head and rotor. bummer is those are the expensive parts. otherwise you have no idea how wore they are, could last a long time could last a short time
 
GW mentioned cleaning the OS, did you try that? Your responded to everything else clearly as done except that is why I ask. With it having sat three years the fuel that would have broke down in there will dirty it up bad, especially if it was off road dyed, or bio mix.

The good side of this is if you do go new ip with everything else sounding positive should be a lot of miles in the future.
 
Will L. said:
GW mentioned cleaning the OS, did you try that? Your responded to everything else clearly as done except that is why I ask. With it having sat three years the fuel that would have broke down in there will dirty it up bad, especially if it was off road dyed, or bio mix.

The good side of this is if you do go new ip with everything else sounding positive should be a lot of miles in the future.
Click to expand...

Well, it's not quite as simple as pull the sensor out, clean it and pop it back in.

The OS is not supposed to be a "field serviceable" part as a DS4 is supposed to be set on a test stand, but it can be done if you're careful enough.

One way is to remove the top of the IP, scribe a line on the advance ring and then remove the sensor. Reinstall against the scribe and hope it's the same as it was.

The other is to frig with it until the calculated idle fuel rates are within spec.

Even with the scribe line, you should verify with the idle fuel rates once reinstalled. It's literally fractions of fractions of an inch in the difference between in and out of spec.

This is how gents used to do the "optic bump" (move the sensor on the advance ring) and if done wrong all sorts of odd throttle and fuel behavior can result. Primarily; overly touchy throttle.

You have to clean in behind the LED "eye". Which means you need to get a jet of cleaner up in there and flush the coke out. The stuff that gets in there is just in the diesel fuel itself and it accumulates over time. Sitting is no guarantee that it is a "dirty sensor" as I've pulled one out of a pump that had been sitting with fuel in it for more years than I know and it worked just fine without cleaning.

As much as I don't want to say it, the OP is getting more and more corralled into the bad OS paddock.

If I didn't know my own pump had the ceramic upgraded bits, I would have put the 300 or so bucks the OS is going to cost towards buying a new pump. Mine was worth saving though.

To the OP: if you were to ask my advice on which pump to buy, I'd go with a new unit from Stanadyne. it's going to cost somewhere around 1500 bucks, but it will last another ten years or so. Stanadyne will have a list of authorized dealers near you. Failing that, they will have a list of authorized rebuilders in your area and it should cost somewhere around a grand. At least you can be reasonably sure you will get the updated components from an authorized rebuilder. Not guaranteed, but better chance than anywhere else.

Of course, if you don't plan on keeping the truck that long, you can buy and OS from someone like Kennedy diesel and swap 'em out if you feel you are "savvy" enough to get 'er done yerself....

:)
 
in addition to scribing the line, I used a set of feeler gauges to get the distance between the optic sensor and the edge of the IP before removing the old one.

I checked the vendor pages and didn't see anyone offering an IP. Heath used to but his new site doesn't list one. You could call him though.

If you're not planning on 10 years, The Diesel Store has rebuilt DS-4 for $940 (they keep the credit card number on file and will only hit you for the core if you don't return it in 30 days. Read the core policy. These aren't the ULSD models though.
 
I use conestoga diesel for my pumps and injectors. They build the moose pumps.

They DONT build a modified ds4 but I have faith that the care they take on mechanical pumps trickles over on their electrical pumps. I have personally never had to buy a DS4, I have 3 spares (not for sale)
 
tanman_2006 said:
I use conestoga diesel for my pumps and injectors. They build the moose pumps.

They DONT build a modified ds4 but I have faith that the care they take on mechanical pumps trickles over on their electrical pumps. I have personally never had to buy a DS4, I have 3 spares (not for sale)
Click to expand...

I also have spare pumps, the rebuilt on mine was on the truck when I bought it many years ago.

DS4 pumps get a bad wrap because of the electronic bits hanging on them but the pumps themselves have been pretty solid in all the ones I've worked on...
 
No I have not tried to clean the OS on my pump yet......... I would think I could do it but I do think that it is far from a for sure thing and dont want to have any real down time with my truck....... I would want to have a good pump on hand to swap out right away if it didnt work, I may do it tomorrow and keep my fingers cross that if it is the problem its all good or if it isnt that the truck still runs well enough to get me to town and back. You guys have all given great advice and really been a HUGE Help with everything! Thanks again I will keep you updated and let you know how tomorrow goes.
 
NEW UPDATE!
Well I did not drive the truck for the last 2 days and this morning I started it and it started right up no hard start! The truck was LOUD Injectors hammering! The injectors are still pretty loud but the truck has all kinds of power (for a 6.5 anyway). I dont know what happened but it seemed like something broke lose inside the pump and is putting out the fuel it should now. It blows some black smoke under heavy pedal. I had put a bottle of seafoam, a bottle of marvel mystery oil, and 1 bottle of PS Fuel and injector service. I guess it just broke down whatever was in the pump and started working, I still have a injection pump timing code that I cleared and about 20 minutes later it came back, I am going to run this new tank of fuel through it and hope that it clears up the code. The injectors being loud and hammering I dont know how long they will hold up...... What do you guys think? Thanks a million for all of your input on my truck I really appreciate it!
 
troe3696 said:
NEW UPDATE!
Well I did not drive the truck for the last 2 days and this morning I started it and it started right up no hard start! The truck was LOUD Injectors hammering! The injectors are still pretty loud but the truck has all kinds of power (for a 6.5 anyway). I dont know what happened but it seemed like something broke lose inside the pump and is putting out the fuel it should now. It blows some black smoke under heavy pedal. I had put a bottle of seafoam, a bottle of marvel mystery oil, and 1 bottle of PS Fuel and injector service. I guess it just broke down whatever was in the pump and started working, I still have a injection pump timing code that I cleared and about 20 minutes later it came back, I am going to run this new tank of fuel through it and hope that it clears up the code. The injectors being loud and hammering I dont know how long they will hold up...... What do you guys think? Thanks a million for all of your input on my truck I really appreciate it!
Click to expand...

pop your scanner on and see what the timing and TDCO values are at....
 
Ok here is what the scanner is saying My tdoc is at -3.1 and my actual injection pump timing is at +25.5 all the time it does not change.......... Desired at idle is 8.5......... I have a 1216b code for Injection pump timing circuit...... IDK It seems to be getting louder and that Timing sounds CRAZY...........
 
troe3696 said:
Ok here is what the scanner is saying My tdoc is at -3.1 and my actual injection pump timing is at +25.5 all the time it does not change.......... Desired at idle is 8.5......... I have a 1216b code for Injection pump timing circuit...... IDK It seems to be getting louder and that Timing sounds CRAZY...........
Click to expand...

OBDII should code any TDCO value over -2.02

+25.5 makes no sense at idle.

Personally, I wouldn't drive it until I found out what was going on. None of that makes sense so you have no idea (the PCM either) what is actually going on inside the engine.

It could be fine or you could be beating the piston crowns, skirts and wrist pins in to an early grave.

What scanner are you using to pull this info?

The electronic 6.5's don't "play nice" with a lot of the aftermarket ones when it comes to timing values.....
 
I am using a OTC Genisys 3.0 version scanner same as a Matco Determinator Idk if it just getting a crazy signal or what. I am going out right now to throw it back on and see what it reads......
 
IDK what is going on ............ Runs great fires right up just the injectors are LOUD!!!!!! Like a cold start in -30......... Here are the pictures of what My scanner is telling me. HELP!!!!!!!


20131001_152623.jpg20131001_152703.jpg20131001_152740.jpg
 
You must log in or register to reply here.
Back
Top