Help! p0087 code

Rickman · 05-26-2008, 12:21 PM

The situation, My truck is an 04 duramax and runs well in the morning but when the heat reaches 90 degrees plus outside the check engine light comes on with the p0087 code. When I stop at a red light or stop sign and push the accelerator it does not go. The truck hesitates and then after about 5 seconds it runs normal, until the next stop light. Sometimes the truck will not go at all and I'm forced to pullover at 5mph, shut the engine off, turn it back on, and wha la, it works. But then happens again when i stop at the next light or sign. I changed the fuel filter out yesterday and it's still doing it. Before I changed the filter out yesterday, I had changed it 2000 miles before that. The truck is all stock with no performance chips or anything like that. What could it be, thanks.

**05_LLY** · 05-26-2008, 12:50 PM

p0087 is a fuel rail psi to low code. Do you know if your truck is a lb7 or lly engine? A few things it could be, are bad injectors, bad fuel pressure regulator, bad CP3 injection pump, bad fuel pressure releife valve (FPRV), or dirty fuel filter.

dose the truck have any other symptoms, such as smoke @ idle, eye burning fumes out of the exhaust, fuel smell in the oil?

Rickman · 05-26-2008, 01:30 PM

The truck is an LB7 and it does not smoke at all. It runs very good. But seems to only experiance problems in the middle of the day when it's super hot. I'll be honest, I did run diesel out of a 55 gallon barrel that had been sitting in a garage for a month. The diesel was filtered while being pumped into my truck though. I've already filled up with regular diesel and it's still acting up.

Rickman · 05-27-2008, 08:36 AM

The problem seems to be getting worst because it started acting up this morning, so I now know it's not related to the heat of the day. I talked to a mechanic yesterday and he said that there's no telling until it's in the shop, but he did say that it sounded like an injector pump problem. He also said that my lb7 is well known for having injector/pump problems due to his previous customers having problems. Anyways, this morning on the way to work, I noticed that I had to push the pedal harder than usual to get the truck to accelerate. I feel that if I continue driving the truck, it's gonna leave me stranded somewhere.

**Bryan@ATS Diesel** · 05-27-2008, 08:49 AM

Fuel filter.......It could be clogged which will be causing your low pressure.

Rickman · 05-27-2008, 11:05 AM

No, it's not the filter, I've changed it twice already. Anyways, a little earlier today I decided to go for a long drive in town with constant stops and goes. Thoughout the 1hr drive I probably put on 35 miles and not once did the check engine light come on nor did I experiance any hesitation problems. The truck ran perfectly fine without a single problem. 2 days ago I added 2oz of standyne cleaner with regular diesel fuel and maybe it cleaned itself out? Don't know, but I hope my truck will continue to now run problem free. Bad fuel maybe? Anyone?

Rickman · 06-12-2008, 09:05 AM

For those interested, I found out that the problem was dirty fuel from a very dirty tank. The truck is running perfectly normal now. Thanks

**BigRedChevy** · 06-12-2008, 09:12 AM

Good to hear you got it straightened out.

DmaxTech1 · 09-24-2008, 08:06 AM

GM TSB for p0087
Recommendation/Instructions:

Complete the current SI diagnostics for any trouble codes or symptoms found. Get a large fuel sample from the fuel filter drain.

If excessive contamination is found, complete current SI repairs for Contaminants in Fuel.

Check the fuel API(specific gravity) with the Kent Moore diesel fuel hydrometer. (Tool number J-38641-B)

If the vehicle has a number 1 diesel fuel, or the diesel fuel is contaminated with gasoline, the fuel API reading may be 39 to 44 or higher.

If a number 1 diesel fuel (39 API or higher) is used during high ambient temperatures it may induce a hard restart.

Get a known good sample of fuel from a nearby fuel station to verify what the normal API would be in your location.

If the fuel found in the vehicle has an API reading of 39 - 44, ( number 1 fuel ) and the fuel sample you compared to has an API reading of 30 - 39 ( number 2 fuel ) , drain the fuel system and refill with a known good number 2 diesel fuel. Evaluate the hard start with a known good number 2 diesel fuel.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.