Losing preasure and my mind.
I will start with saying this is the best forum I have found in two years dealing with the same problems everyone else is.. Let me start with letting everyone know I purchased my 06, 4x4 crew 3500 new. I hauled 4000 to 10000 lbs coast to coast on random trips up to 75k miles. My normal travel was under 25 miles a day. In 2011 I started a new business in underground and started hauling 14K trailers 2 to 4 hour trips weekly, leaving my truck idle for 10 hours a day ect. Things were great until the August of 2012 while driving in 100+ temps on fresh blacktop... Engine code came on truck went into limp... After spending 2 months and 2000 dollars at 5 dealers getting 4 fuel filters on my 105K millage (out of warranty) truck I was pissed 4-5k to fix, no forums supported this as a solution that worked. I complained about the 250 degree fuel temps and was told by GM that it would have no bearing and was normal. I then discovered the fuel heater was stuck on and boiling my fuel for two months. Changed the entire fuel primer assembly and drove 65K last year no problem leaving the heater unplugged. (as mentioned here). The entire time the code comes on but only failed again this year. I have had my truck drop into limp mode as many as 15 times in 400 Midwest miles using only a 5 min restart on the highway.. Code does not clear but truck wants to run at 80 with a load... No rime, no reason...
My problems:
Heat outside 75 to 100+ Yes
Load causing failure Yes
Large hills with headwind Yes
Quick slow downs under load YES
tired of dealing with YES
I'm not clearing codes but once every few months but never have a performance issue until above conditions exist. I'm 100% stock, the Black Pearl works hard and gets stretched maintenance.. This is the best vehicle I have ever owned but I need a real solution to a heat/load related issue that does not require a engine rebuild.
220K with 7200 hrs and still breaks the tires loaded with 4 men, tools and trailer...
BTW: 50+ professional drivers with no CC and tuners. No problem from 100 to 400K on trucks....
Possibly a fix for the mystery p0087
First of all, let me say thank you to the forum and its members for providing such great information that anyone with Google can find. My hat is off to you!
I've been battling a p0087 in an 06 GMC 3500 used to haul containerized trees around South-Central Texas. Tall and heavy loads, heat, head winds, and hills are all a part of 95% of the miles on this truck.
When the p0087 first showed up at 120k miles (18+ months ago), I immediately Googled it and after reading through numerous forums, I decided that ultimately the injectors are to blame, I skipped the rigamarole of debate and went ahead and had it done. A big chunk of change sure, but delivering is the most important aspect of our business and without our sole delivery truck, we weren't making any profits.
Fast-Forward to mile 155,237. A hot day in early June, heading from Columbus to Austin, a load no heavier and taller than any before. 30 minutes after leaving the farm and bam, code. Going up a hill, truck downshifted to 4th, (no cruise, tow/haul on) and hiccuped. A long miserable day of sitting on the side of the road, waiting for the code to auto clear. Anyway, by the time I got home, the code had thrown a grand total of 8 times (5 loaded, 3 empty). I hadn't seen this code in over 25k miles, and now 8 times in one day? What gives?
I read through this forum last week and have compiled a laundry list of things to do first. And was ready to get to work when...
My Schaeffer's rep called. This gentlemen truly has been there, wrenched on it, and lived to tell about it. So I ask him what is your take on a low fuel rail pressure code in a common rail diesel? With out a hesitation, "Your return lines are clogged."
Say what?!?!?!
"Well its simple sonny, your not flowing what is needed to keep the diesel fuel and associated parts cool. Your diesel is getting hot and your pump can't pump it. Its too thin."
My eyebrows are raised as I've read multiple people complaining about high diesel fuel temps. "Go on..."
"American diesel is junk these days. It grows algae and no one ever cleans their stock tanks. Everyone of those companies are selling junk diesel. He**, they're buying it as junk right off the tanker at the Gulf! There is algae growing in every stock tank in America, I don't care how cold it is."
So what is my fix?
"Shock your tank, Schaeffer's Fuel Shock #285. It'll kill that algae living in the plastic tank and in the aluminum lines. It'll clog your filter to hell but it'll work."
OK, how much?
$72 per gallon. One Gallon treats 4,000 Gallons of fuel.
Really? Give me a bottle.
Got me a turkey baster and shot 1 ounce of this stuff into each 20 gallon tank yesterday afternoon. Made a delivery this morning, no code, but the 3500 didn't quite have the gusto I was expecting. Maybe we need some more miles I thought. Got home, unhooked the truck and was authorized to joy ride the remaining 25 gallons of diesel in the tank away.
On the very first punch to get on to the highway, she heaved bad, AND THEN ROCKETED AWAY! This truck hasn't accelerated like that in a loooong time. That wasn't a down shift heave either, she was already winding up in a lower gear. This hesitation came right in the middle of two gears. When I lurched forward in my seat, I thought for sure I was going to get chewed out for destroying the truck...
Called my Schaeffer's rep. He explained to me that algae actually grows into the pores in the plastic and aluminum. You can't pressure wash that stuff out. Petroleum cleaners aren't terribly effective. I can't pronounce what is in this bottle but it definitely is some sort of organism killing stuff.
I'm off to finish burning those remaining 20 gallons and change my fuel filter. Next tank is getting Schaeffers #137. I'll post back after the next delivery. Until then...
p0087 code THWARTED! and a few other thoughts
An update from my previous post for anyone still working on this.
Did not have an opportunity to run the truck last week, no deliveries came up.
Used all the "old" diesel, installed a new fuel filter, drove around town a bit last week. Delivered a moderate load today, certainly not qualifying as "heavy". Headed to Austin on Hwy 71. 18 miles from the farm (about 60 on the fuel filter) and code thrown. A/C on, Cruise off, tow haul off, just driving normally, trying to keep above 70 mph, 81 degrees out, wind left to right 15-20 mph, moderate incline (nothing near 6%).
Modified my driving habits mid trip. I would accelerate down hill and refrain from depressing the accelerator pedal when headed up hill. Even pulled my foot out of the pedal on some of the steeper inclines.
Got to a section of 71 where there are some traffic signals. Used this opportunity for some full throttle acceleration. Couldn't get a code no matter how hard I mashed the GO! pedal. This is interesting to me. I'm getting up in the rpm range, I'm figuring my injectors are staying open a little longer, turbo is winding up, boost PSI is pretty up there, this motor is giving it everything it has, demanding higher fuel rail PSI. Why no code, especially with the injectors staying open longer dumping more fuel? Sure the CP3 is spinning faster, probably has a pretty good vacuum on the suction line (any hose pinching problems should be pretty obvious).
It got me thinking about it, this code is throwing under 2,000 rpm in high speed and loaded conditions in high gear.
Got to the delivery site without much opportunity for further testing. Oh well. Continued to ponder on the drive home from Austin and took the opportunity to test a little more.
I've narrowed it down to these conditions:
(1) Transmission in drive
(2) Any speed with the transmission in 6th gear (for me 52 mph or higher)
(3) A slight depressing of the go pedal while going up hill (even some not very steep) (pushing it to the floor makes the transmission down shift)
(4) A trailer connected (even an empty one)
With these conditions, this code throws every time.
So I popped it into manual (M on the dash) and selected 6 as my range to see what happens. Couldn't get the code to throw to save my life. I even turned around and went back to the last hill the code popped on. Still couldn't get it to do it.
So for now, I'm driving in Manual.
Further thoughts: Why does this code pop only at highway speeds with slight desired acceleration? Something to do with the transmission and engine communication? Anybody know how many sensors are in an Allison transmission? Why does the transmission, under full throttle acceleration, shift from 4th to 5th at 2700? Why is there a 6-700 rpm drop going to 5th? My foot is still in the pedal, I wanna stay up in the power band, not drop below it. Why, when the code throws, am at 92% (or more) calculated load? Where is this load measured or how is it figured? Why does my truck think it is so loaded with an empty trailer weight of 3,000? Is my transmission causing the increase in resistance? We've religiously maintained the axle bearings on the truck and trailer, they spin very easy by hand.
I'm beginning to think my problem isn't in the fuel system, its in the transmission. Something is telling my fuel system to go to max PSI with a slight depression of the accelerator pedal, WITHOUT down shifting the transmission, allowing more RPMs, boost PSI, etc.
Anyone know anything about an Allison 1000 transmission? I found this video:
http://www.youtube.com/watch?v=8xFwoTCInY8
(According to this video, Allison 1000 gear ratios are 3.10, 1.81, 1.41, 1, .71, .61, hence the big drop from 4th to 5th and the only slight drop from 5th to 6th.)
Do I have a failing torque converter? A faulty pressure sensor in the transmission somewhere? A leaking valve body? Is there anywhere I can plug my scanner into this thing to find out? (No there isn't, unless your trans is post 2009, when "prognostics" was added).
I remember older transmissions had a "dump" valve that was mechanically operated by the opening of the throttle. In higher gears, this valve would cause enough loss of fluid psi to down shift the transmission allowing the torque converter to spin faster and thus re-raise fluid psi while accelerating the vehicle. How is that accomplished these days with all this wiring harness connected to this transmission?
Trying to out smart my Duramax...
Quote:
Originally Posted by
Kennedy
The chemical treatment has not cured your P0087 code correct? It does not appear so. Oh well. :p
Modified driving habits have helped you skirt around it correct? Yes, but why does operating the truck in manual mode (with 6th gear selected) and driving normally not cause a code? Is the ECM in a different set of parameters for operation or something?
I will stick with my original comments that this is fuel supply related:
A lift pump keeps the system under pressure happier and healthier
Secondary filtration keeps the fuel system happier and healthier
Regular use of a quality fuel treatment will often pay for itself with a small bump in economy and keeps the fuel system healthier and happier
Now as to the issue, heavy load high gear low RPM high ambient temps and very high fuel temps are the factors. The return flow is greater than expected due to injector wear. When operated in these conditions, the pump flow is insufficient to maintain demand. I have had some success with manipulation of the pump though ECM programming as IGO1320 has reported. Not 100% surefire, but pretty darn good.
I'm speaking for myself, but I had Lite Load, high gear, low RPM, moderate ambient temps (it was only 82 degrees yesterday). If a brand new set of injectors is wearing out after 25k miles, either the filter isn't doing its job or the CP3 has gotten weak (or the dealership installed crappy injectors, known to happen...:mad:). But others have posted here that replacing the CP3 didn't work either.
I'm not convinced a fuel supply problem, this code should be popping up under hard acceleration (mashed pedal) & loaded conditions if fuel supply was the issue.
Correct me if I'm reading the wrong information but the CP3 is mechanically powered off the cam chain. The only way the ECM can modify fuel pressures is with valve bodies in the CP3 and the FPRV.
What if I have a leaking intake system (think air entering the system AFTER the MAF)? Under high RPMs (more than 2k) vacuum could suck the leak closed, under low RPMs not enough vacuum to pull it closed. Is there an 02 sensor in the exhaust or something reporting exhaust conditions to the ECM? If so, it could be reporting excess 02 (compared to the MAF) and the ECM is trying to compensate by commanding more PSI than the pump is physically able to provide at under 2000 engine RPMs.
I'm still miffed that the transmission doesn't down shift out of 6 with any light/moderate depression of the accelerator pedal, this just doesn't seem normal to me (especially in "Tow/Haul" Mode). If this is truly the case, the transmission can take a lot more torque than the motor can provide (ie, at 65 mph and ~1600 rpm, the transmission is telling the motor "you aren't overloading me, no need to down shift" and the motor is struggling to put out the power to keep the vehicle/trailer going up a moderate incline).
http://www.dieselpowermag.com/featur...a_3500_review/
According to this article, the LBZ outputs 650 ft-lbs at 1,600 rpm. Times .61 (6th gear ratio) = 396.5 ft-lbs of torque at the back of the trans, times 3.73 rear end ratio = 1,478.95 torque @ 8.25" ring gear divided by 3.6 (tire diameter 29.75" divided by ring gear diameter) = 410.82 calculated torque at wheel/pavement contact of a brand new from the factory vehicle. Is that enough for approximately 10,600lb vehicle combo (~6600 vehicle (I have crew cab, "8 ft farm bed" + tool box and 2 20gal tanks) and 4,000 lb empty trailer) at highway speed up a moderate incline? Never mind the the power lost to heat, windage, alternator, a/c system, 150,000+ miles of wear on the engine, etc.
All that said, perhaps I have a clogged up catalytic converter? After 150,000 miles of dirty diesel (approximately calculated 18,750 gallons) causing excess hydrocarbons in my exhaust... Clogged cats can cause higher engine compartment temps. Anybody else noticed that the fuel supply lines are rather close to the drivers side exhaust manifold and the water separator/fuel filter sits right next to the passenger side exhaust manifold? And since the LBZ has EGR cooling, those hotter exhaust temps are flowing through the air cooler, raising temperatures entering the engine compartment. Now we have heat added all over the place due to a clogged CAT. Is this train of thought out of whack?
Has anyone with the catalytic converter delete experiencing the p0087?