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My 6.5 ran perfect Sunday morning! not the dog like usual. But I don't know why?

N

nealpellecchia

Active Member
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Location
Visalia, Ca.
I used to notice this when very low on fuel and suspected it was related. Full advance power real soon and it is now no dog! The new air filter is still in the box too. So what gives? Gas cap venting I thought too might be related. Fuel pump on the rail.
 
Tell us more about what kind of truck you have..... Year, model, F or S engine code, is it all stock or have you done mods, how many miles, any smoke from the exhaust, etc........

We will definately help you out, just have to know a little more to get started.
 
Chief915 said:
Tell us more about what kind of truck you have..... Year, model, F or S engine code, is it all stock or have you done mods, how many miles, any smoke from the exhaust, etc........

We will definately help you out, just have to know a little more to get started.
Click to expand...

An F, I have no S's. 93 Silverado 6.5 Turbo Diesel 4L80 E 4 wheel drive HD. No modifications, got from my brother at 100,000 mile I put on on 210,000 miles. He went through 5 tranney's I fixed 1. But that's another story.
 
nealpellecchia said:
An F, I have no S's. 93 Silverado 6.5 Turbo Diesel 4L80 E 4 wheel drive HD. No modifications, got from my brother at 100,000 mile I put on on 210,000 miles. He went through 5 tranney's I fixed 1. But that's another story.
Click to expand...

Oh!, Ok I get smoke when going down hill with my foot a little on the accelerator to maintain speed most of the time. Sometimes no. In fact I got a ticket for it and thought the new supply pump fixed it. I have to push it past 70 and coast back to 65and repeat to minimize the smoking... now only a bit when you first hit it. Not black smoke I guess blueish white.
 
Blueish white smoke is normally bad news..... Especially enough smoke to get a ticket.....

Do you ever have to add oil or antifreeze to the engine? If so, how much and how often?
 
it's only on a long down hill, I think smoke is darker. Assumed it was timing...low advance on low throttle with the engine turning fast already... it can't take anymore fuel. Or it only happens when the advance piston is stuck or slow. Antifreeze? what would that do? Has exhibited this problem for years.
 
antifreeze going into the combustion chamber, through a crack or bad head gasket, can cause low power and white smoke.

If it's been doing this for a long time and you haven't been losing antifreeze....then that probably isn't your problem.


Does it seem to run alright while it is having low power and smoking? Any missing, rough running, or strange noises?
 
Free stuff first. Try driving with the fuel cap loose. A plugged vent in the cap can cause fuel starving[doggy] How old is the fuel filter?
The downhill smoke is normal. My dad's Dodge would do it also.
3 trannys is unusual with those miles. The 4l80e trannys are very stout. I have more than 1 with close to 300,000 miles on them. The TCM[transmission control module] are somewhat failure prone much more than the tranny itself. Here;s a thread on replacing all the electrical components in the tranny for $135 http://www.thetruckstop.us/forum/showthread.php?29925-Installing-A-Electrical-Kit-In-A-4L80E
 
how much oil consumption do you consider normal? decelerating or going downhill with blue smoke would usually indicate oil getting past the rings. Might check the cdr
 
Fight the ticket, It is a 1993 and the emissions on those years you can see smoke. Ever change the injectors?
 
Brooklyn Tow said:
Sounds like your your turbo starting working.....Maybe Boost solenoid stuck open......WAG
Click to expand...

93 has no boost solenoid but wastegate actuator[gm turbomaster] may have been stuck open untill sunday. Check for binding or stiff linkage.
 
bk95td said:
Free stuff first. Try driving with the fuel cap loose. A plugged vent in the cap can cause fuel starving[doggy] How old is the fuel filter?
The downhill smoke is normal. My dad's Dodge would do it also.
3 trannys is unusual with those miles. The 4l80e trannys are very stout. I have more than 1 with close to 300,000 miles on them. The TCM[transmission control module] are somewhat failure prone much more than the tranny itself. Here;s a thread on replacing all the electrical components in the tranny for $135 http://www.thetruckstop.us/forum/showthread.php?29925-Installing-A-Electrical-Kit-In-A-4L80E
Click to expand...

it melted the overdrive sprag 5 times one time proceeded to break the shaft. I added coolers 2. My brother thought the engine oil cooler was a trans cooler. The 4l80 e is a car trans.,when i pull that 3/4 ton up a long hill i put it in 3rd gear. I installed a trans temp to know where i'm at. people said that the trans didn't look like it over heated just the sprag parts. once they were so hot after the plastic cage melted they welded stuck to the other parts in the overdrive section. a guy also stated that it's the sprag with all that weight on it...it keeps the trans from turning the other way...the heat is hotter their than elsewhere in the trans. MY guy also said that you don't need a heavy duty torque converter or a heavy duty sprag. just drive right and no over drive driving up steep hills.
 
bk95td said:
93 has no boost solenoid but wastegate actuator[gm turbomaster] may have been stuck open untill sunday. Check for binding or stiff linkage.
Click to expand...

good info!! I'll look into it, also like the driving with loose gas cap. seem to get an intermittant plugged gas cap. You can hear the pressure release when you take it off.
 
agree with bk95td, when was the fuel filter last changed?

could a plugged filter that finally ruptured cause the newfound power?

if the transmission was a 4L60E, that replacement rate would be more realistic. the 4L60E is the car transmission IMHO. the 4L80E transmission is a truck/SUV transmission, and is very durable. I would look into a different rebuild shop.
 
Just a thought..... maybe the sock in the tank was clogged and the stuff broke loose? Did you use any additives? I put a new sending unit and gas tank on mine this weekend and I swear its like driving a totally different truck! I agree check those filters. I think there is also a tread on here about drilling out the gas cap.
 
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