Poor running when Cold

[KansasDiesel]

my truck runs poorly when it's cold as well, but when it warms up everything works great. could that be a problem or is that kinda normal?

Normally the truck will run smooth after start up. And intermittently I have a rough idle, where you can not only hear the miss but also see the
Tach drop.

The no start problem after it has been running a min. or two only happens when the OAT is below 40*. Above that It usually dose not die on me.

 

[JOAT]

I had a chance today to connect my Auto Enginuity program up to her.

I ran the Cylinder Contribution test, the results were:

P0263 Cylinder 1 InjectorContribution/Balance Fault
P0266 Cylinder 2 InjectorContribution/Balance Fault
P0284 Cylinder 8 InjectorContribution/Balance Fault

Can anyone give me some insight on what this means? Do I have an injector problem there? The Buzz test was normal.

Was this hot or cold? I'd try the contribution test both ways and see what happens. If you end up with the valve covers off at some point check the injector armature clearance. Possible some wear there is causing poor injector operation till heat causes expansion. Just a wild guess tho...

Another thing worth checking is an EOT sensor or wiring issue, tho that wouldn't explain the rough idle. Try disconnecting it for awhile and see if there is any change when it's running the default program. Some PCM's default to a cold setting when it's disconnected and some to a hot setting. If it defaults hot and the truck is cold, it will be gutless till the engine warms up. May help narrow things down a bit, maybe not...

 

[KansasDiesel]

Was this hot or cold? I'd try the contribution test both ways and see what happens. If you end up with the valve covers off at some point check the injector armature clearance. Possible some wear there is causing poor injector operation till heat causes expansion. Just a wild guess tho...

Another thing worth checking is an EOT sensor or wiring issue, tho that wouldn't explain the rough idle. Try disconnecting it for awhile and see if there is any change when it's running the default program. Some PCM's default to a cold setting when it's disconnected and some to a hot setting. If it defaults hot and the truck is cold, it will be gutless till the engine warms up. May help narrow things down a bit, maybe not...

The test could not be done cold, i tried, I kept getting a message like oil temp too low. So the test was done at operating temp.

I will look into the EOT thing. I should have a chance Friday and Sat to look at the truck, if it doesn't rain.

 

[action4478]

This problem has been occurring every winter for the past 3 years, that I remember. When cold and not plugged in, She will start and run but if I do not let her warm up and just start driving she will die and then takes several times to get started again. I also have a miss at idle that is intermittent.

I thought it could be the EBPV that was causing it, but that was gutted last summer.

Yesterday was the kicker, while letting it warm up she died and it took forever to get her running, once I got it on the road, I noteced the miss at idle worse and not only at idle.

When it warms up here I plan on doing a compression check and trying to figure this problem out, but until I get it fixed I can't trust not getting stranded.

Any ideas?? where should I begin??

NOTE: This problem was occuring before the WVO conversion so I am taking that out of the equation. Actually it runs at idle a little smoother on WVO but occasionally still has the miss.

Read here...


http://members.cox.net/calico5string/HPOP Manual.pdf

Scroll down to # 5). read about the oil...

 

[JOAT]

The test could not be done cold, i tried, I kept getting a message like oil temp too low. So the test was done at operating temp.

I will look into the EOT thing. I should have a chance Friday and Sat to look at the truck, if it doesn't rain.

Sorry, I always forget to mention this. In order to do the test cold you need to disconnect the EOT sensor and jumper a resistor across the leads to make the PCM think the oil is hot, then you can run the CCT. IIRC a 5k ohm resistor works, but I'll check my notes to confirm.

EDIT, looked at my EOT mod cheat sheet, 5k may be a bit high, try 2k ohm resistance. 96-97 however have a different resistance curve and I don't have that info handy. I still think 2k would be fine tho, as the main difference on newer EOT sensors seems to be at colder temps.

Also, the fact that you can't run the CCT cold now but can hot indicates the EOT sensor is behaving properly, so probably no reason to suspect it. Still, trying a CCT and Buzz cold may give different results and could be somewhat useful in diagnosis.

 

[KansasDiesel]

Read here...


http://members.cox.net/calico5string/HPOP Manual.pdf

Scroll down to # 5). read about the oil...

Great link... #5 sounds like what has been happening. I will also investigate.

 

[JOAT]

Great link... #5 sounds like what has been happening. I will also investigate.

Interesting. Besides an oil change you might want to take a sample of old oil and new oil and throw them in the freezer overnight. Compare the thickness. Also if you have any polymerized veg in there it will create jelly like chunks or extra thick oil.

Have you checked the level in the HPOP res when it doesn't want to start?

 

[KansasDiesel]

Interesting. Besides an oil change you might want to take a sample of old oil and new oil and throw them in the freezer overnight. Compare the thickness. Also if you have any polymerized veg in there it will create jelly like chunks or extra thick oil.

Have you checked the level in the HPOP res when it doesn't want to start?

Funny you should mention this, I happen to be at oil change time 3000 miles. So I decided to change the oil, remove all the oil in the HPOP. New fresh oil and connected my AE went for a drive expecting to gather data of the problem. Well the idle isn't rough and it hasn't had the hesitation or dying problem. I am also using an additive right now that has helped a friend with carbon buildup in his MB. I believe this is helping too.

I think the oil was the problem right now.