• 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!

Hard start & very rough engine

matuva

matuva

Tropical 6.5er
Messages
1,996
Reaction score
21
Location
New Caledonia. An island in south west pacific, cl
Howdy all,

we're facing a problem with a 1997 K1500.

She is very difficult to start, does after several cranking, and when she starts, the idles is very rough, throwing a lot of black smoke.
If you let her idle, she will run very low, about 500 rpms or less, rough, and die.
You can rev it up a bit, always rough and smoking a lot, and as soon as you release accelerator she dies.

More than a month ago, she has been experiencing stalls previously, because of a dead PMD.
Being a bit short of money, he tried to keep running with a used PMD, with more or less luck.

While she was experiencing this PMD problem, we hooked a laptop with AE scanner, and here are the codes we found :
several ones about shift,
others about IP. Note the PO266 showing : cylinder 2 injector circuit contribution / balance defaut
Despite these codes, she was running fine, except stalls
Evan's DTCs- 01-06-2009.jpg

Yesterday, we received the new D-Tech PMD and install it, remote mounted on a heat sync (the one from SSDiesel kit), outside engine bay.
The guy crank, and shefired right away, idling like a charm.
He let her iddle for a while. After 5 minutes, she started herself idling down to 500 rpms and started stumbling hard, black smoke, and died.
He killed batteries to try starting her again, as she was stalling after few seconds.
Then, we tried to swap to the old PMD which was causing stall but was allowing to run fine : same result.
- We pull out the resistor from PMD (#9)
- We connected the PMD on the stock harness to see if te extension was fine
- we disconnect both batteries, then disconnect the PCM for a while
still no luck.

The AE scanner shows these codes :eek: :
Evan's DTCs- 24-07-2009.jpg

I forgot to mention that the IP is 3 months old and was said to be brand new..., remember at previous scan, that P0266 was showing...


What the hell mean these codes ?

After we disconnect the PCM for a while, cyl 1 and 5 do not show up in the code list, and she was running just a little smoother...

any idea ? we're a bit lost, and the young guy is really really sad and disappointed...
 
Some recent advice hit me quite accurately from this site. Always consider the thing you think you just fixed; you may not have. This makes the IP suspect. I think if it had been installed it properly, it would either run well, or run poorly. Since it ran well, we must assume it was properly installed. Well done.

This leads me to consider the IP may be failing. Hopefully under warranty.

Did you note fuel pressure?

Good luck to you, and remember, it's only a guess you read on the internet. Beautiful work bringing your scans into the forum. Good idea.
 
I agree with Veg Out, Is the timing good?

I would also go through the grounds.

Leo
 
with the remote mount pmd did you leave the ground on the pump? And then run a seperate ground for the remote mounted new one?? Is the extension harness bought or homemade.....either check that..
 
625fireman said:
with the remote mount pmd did you leave the ground on the pump? And then run a seperate ground for the remote mounted new one?? Is the extension harness bought or homemade.....either check that..
Click to expand...

You know, I don't remember my Heath remote grounding itself at the remote location.
 
Check grounds but no change. Ground is on IP, extension harness was bought and was working fine...
Going from good running engine to this crappy thing in 5 minutes is weird.
Could it be the PCM ? IP harness ?
Any knows what means injector "circuit contribution / balance defaut" ? There are so many of the injectors involved suddenly that I can't believe they are, mechanically, culprits.
I bet that might be an electronic problem, but can't find which one...
 
Al

is filter mgr full of fuel/lift pump healthy/tank sock clean, as it ran up then died and has no start now, lets progress from tank to IP 1st, when you jumper the lift to run what is the pressure reading on the lift pump output? Air in fuel causes imbalance, last week I changed my IP it took a while to purge the air from it, it ran sub idle and rough for a long time until it cleared it'self of air, 1st several goes at it it died.
 
Tim,

the truck was sitting in the garage for 2 weeks because of a PMD issue. At the time the owner stops it, she was running fine, just experiencing stalls and intermittent reving up.
A scan I performed on beginning of june already shown a problem on injector # 2.

Yesterday he puts on the new D-tech, she started right away, run fine for a few minutes, then suddenly idle went low then she stumbled and "black smoked" a lot.
The first scan (that I didn't recorded) shown that all cylinders/injectors but #3 were supposed to be in trouble.
After disconnecting the PCM, the second scan looked a bit better as #7 wasn't listed.

Lift pump looks fine.
I didn't open the fuel filter manager to check inside. The fuel I can see in the fuel/separator installed between lift pump and fuel manager appears clear and fine, not cloudy

She's blowing a lot of black smoke, should that mean that there's a lack of air, though I tried to run her without the air filter : no change ?
There's also a strange noise coming from the intake, about the same as if something is blowing inside, coming from the engine :confused:

Should I check EGR and EGR pit in the plennum ?

I'll try to see after today job if I can find something wrong in fuel lines and will double check the lift pump----
 
Yes check to see if donut gasket is intact between upper & lower when I was still S equipped I found mine partially rotted away, which causes a full time flow of waste gas, also this trouble started after a IP swap ??? or just just the driver,

If a IP I'm thinking that maybe your timing needs advancing, runs good while TSM is active advancing time on "cold engine" but as it warms up and less advance then you have shutdown and hard start issues, does your scan tool have time set function ??? need to do that and see where the avg is in time set.
 
OK. we cured it.

The culprit was the CPS.

I had a spare one in hands and we decide we must change this :soapbox sensor , the engine running like if it is not timed properly.

She fired then almost well, much better, and smoother. The first scan shows 4 more cylinder/injectors faulty.

I initiate a time set, shut and restart. Smooth! No more codes!

The smile I saw on the young owner's face was worth the time spent laying under the engine cussing while fighting with the CPS.

We will all sleep better tonight :D
 
You must log in or register to reply here.
Back
Top