Question about 1999 Chevrolet Silverado 1500

Open Question

Code p0140 diagnostic

I drove my truck my sons to my house, about 25 miles, the truck ran great. The check engine light came on about five miles from home.I pulled over,checked the truck over,couldnt see anything wrong,so continued home. shut down truck,read obd11 codes, had p0140.cleared codes,tried to start truck. turns over fine,has spark,would not start. I suspected pump module so I banged the tank repeatedly with no success. I tapped the evap sol.(mounted by tank on frame) it "pumped" 6 or 7 times and the truck started.Can this stop the truck from starting or was it just a fluke?

Posted by on


6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya Mechanic can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

  • 1 Answer

SOURCE: 1989 Chevy Truck 350 Stalled Wont Start After I filled Gas Fuel

You need to check the fuel pressure to the TBI. I just fought one which was doing the same thing. I pulled the fuel tank to replace the fuel pump. It turned out to be the short hose from the fuel pump to the steel line coming out of the tank. It had a split in it so I wasn't getting enough fuel pressure. Some places show two pumps available. One you can pull the unit and replace just the pump. The other the pump and sender are all one unit. Hopefully you have the first one. The second is around $300.

The easiest way to get to the top of the tank is to pull the front 6 bolts mounting the bed and loosen the back two. Take the three screws from the filler neck and unhook the rear axle vent tube. You can then take an engine hoist and lift the front of the box. You can get right to the pump and gauge assemble in the top of the tank. Most times, this works easier than emptying the fuel tank and removing it.

Posted on Dec 18, 2008

  • 15935 Answers

SOURCE: 2001 Chevy Malibu, 89,000 miles, 3.1 engine, won't start

CLICK HERE for the injector schematic.
CLICK HERE for the Ignition schematic.

Since the PCM uses info gatheres from the crank and cam sensors to calculate ignition - and there are no OBD codes - in all likelihood, the PCM itself is bad.

The Ignition Module, also transmits to the PCM.

It appears after all your testing - that the PCM is at fault.

It does not error report on itself (unfortunately).

The ignition timing is controlled by the Powertrain Control Module (PCM). No adjustment is necessary (distributorless ignition) or possible.

Please see the following....

The ignition timing is controlled by the Powertrain Control Module (PCM). No adjustment is necessary or possible.
The engines covered by this manual are equipped with distributorless ignitions, ignition timing is controlled by the Powertrain Control Module (PCM), as applicable. No adjustments are possible. If ignition timing is not within specification, there is a fault in the engine control system. Diagnose and repair the problem as necessary.
Ignition timing is the measurement, in degrees of crankshaft rotation, of the point at which the spark plugs fire in each of the cylinders. It is measured in degrees before or after Top Dead Center (TDC) of the compression stroke.
Ideally, the air/fuel mixture in the cylinder will be ignited by the spark plug just as the piston passes TDC of the compression stroke. If this happens, the piston will be at the beginning of the power stroke just as the compressed and ignited air/fuel mixture forces the piston down and turns the crankshaft. Because it takes a fraction of a second for the spark plug to ignite the mixture in the cylinder, the spark plug must fire a little before the piston reaches TDC. Otherwise, the mixture will not be completely ignited as the piston passes TDC and the full power of the explosion will not be used by the engine.
The timing measurement is given in degrees of crankshaft rotation before the piston reaches TDC (BTDC). If the setting for the ignition timing is 10 BTDC, each spark plug must fire 10 degrees before each piston reaches TDC. This only holds true, however, when the engine is at idle speed. The combustion process must be complete by 23° ATDC to maintain proper engine performance, fuel mileage, and low emissions.
As the engine speed increases, the pistons go faster. The spark plugs have to ignite the fuel even sooner if it is to be completely ignited when the piston reaches TDC. Spark timing changes are accomplished electronically by the engine and ignition control computers.
If the ignition is set too far advanced (BTDC), the ignition and expansion of the fuel in the cylinder will occur too soon and tend to force the piston down while it is still traveling up. This causes pre ignition or -knocking and pinging-. If the ignition spark is set too far retarded, or after TDC (ATDC), the piston will have already started on its way down when the fuel is ignited. The piston will be forced down for only a portion of its travel, resulting in poor engine performance and lack of power.
Timing marks or scales can be found on the rim of the crankshaft pulley and the timing cover. The marks on the pulley correspond to the position of the piston in the No. 1 cylinder. A stroboscopic (dynamic) timing light is hooked onto the No. 1 cylinder spark plug wire (2.2L engine only, on the 2.4L engines, special adapters are needed) . Every time the spark plug fires, the timing light flashes. By aiming the light at the timing marks while the engine is running, the exact position of the piston within the cylinder can be easily read (the flash of light makes the mark on the pulley appear to be standing still). Proper timing is indicated when the mark and scale are in specified alignment.

WARNING When checking timing with the engine running, take care not to get the timing light wires tangled in the fan blades and/or drive belts.

The engines covered by this manual are equipped with distributorless ignitions, ignition timing is controlled by the Powertrain Control Module (PCM), as applicable. No adjustments are possible. If ignition timing is not within specification, there is a fault in the engine control system. Diagnose and repair the problem as necessary.

Thanks for using FixYa!!

Posted on Aug 18, 2009

  • 3433 Answers

SOURCE: 2001 Chevy Cavalier won't start

MY turn! OK, Fuel system, supply and demand. Once upon a time, someone thought of a way to have a vehicle imitate a humanNow a car exchanges tons of information and the result is the same. the whole mass gets confused about the objective and that is to get moving.
A quick run down on efficiency. There are numerous sensors in a motor vehivcle but we will just touch may the five or six that count. Furst we have thefuel pimp. Supply only on demand. If the fuel syatem maintains a residual pressure in the fuel system it will no have reason to prime. The vapor recovery system and gas cap only recycles fumes that condense and gives the left overs to the engine.Hence hard starting because it screws up the air fuel ratio by bypassing thesystem fuel controls. Which are: The coolant temp and the intake air temp sensors. These two team up to function as the choke/cold start like in the good old cars,They enrich the fuel on startup.Once he engine and air temps are optimal, they allow the fuel mixture to be controlled bt the Mass air flow sensor. This sensoris mounted inside a rigid section of the intake ducting. Once it takes over, it starts reading the density, volume and velocty of yhe intake airand through the ranges meters the proper amount iof fuel in relation to the air being induced. The throttle positioning vavle simply lets the fuel get to the injectors according to how much ias requred to get the desired results.smoothly.. The air filter condition is critical because it impedes air flow and if in poor shape filtration wise, it allows dirt to accumulate on the MAF sensor sensing componants.In the event the MAF cannot read properly it affects the fuel supply directly by ling to the computer. A dirty sensor reads low air volume and velocity and cuts back on the fuel, leanning it out and the vehicle stalls, runs rough, hard starts, and surges. AND, we have arrived back at Dennis.and his dilemna. Vehicle unreliable.. As you can see, the other sensors are in the shadows right now. In the shadow of the MAF sensor. The MAF SENSOR CAN BE CLEANED using only CRC electrical spray cleaner. Thoroughly wasjing(rinsing) the sensor avoiding touching, rubbing, or brushing. The spray cleaner dries rapidly and compressed air must not be used.. Once cleaned, everyone should be "on the road again" I hope this info helps you dennis.. Good Luck-Ned

Posted on Sep 24, 2009

  • 1 Answer

SOURCE: fuel pump not working

I am have the exact same problem but my ground seems to be intact and getting a good ground. Do you have any other ideas on what may be cause the Fuel pump not to kick on?

Posted on Oct 13, 2009

  • 617 Answers

SOURCE: 1978 Chevy 1/2 ton Truck - fuel is not getting to

On the front of the carburetor where the fuel line comes in is the fuel filter.Did you change that?Take off that line and slip the end into a container,coffee can size.Have a friend turn over the motor,watch for fuel.If you get fuel your needle and seat have seized in the closed position.No fuel check the rubber lines that hook to the fuel pump.You replaced the pump,it's only $2 worth of rubber hoses.If they don't seal the pump can't pull the fuel,it's cheap insurance.

Posted on Jan 05, 2010

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

2001 buick lesabre ltd...diagnostic code P0140..what parts are needed to turn off check engine light for inspection?

Before replacing a part diagnostic's for code P0140 need to be done . May not be a part , could be wiring , PCM etc....

Aug 23, 2017 | Buick Cars & Trucks

1 Answer

Car sat in parking lot for 3 days, with a lot of rain. Upon start up Check Engine & VSC began to flash. Car ran normally for 2 miles. Pulled over shut down car, waited 10 seconds re-started engine...

It likely had water on the ignition system. The check engine light will flash for misfire. The VSC light is on just because the check engine light is on. You likely have it dried out now and its fine. You just need to clear the codes. Autozone will do this for free.

May 30, 2011 | 2008 Lexus Rx 350

3 Answers

2002 express 1500 van, will not start

remove dog house locate test port and install guage should be 45-60 psi

Mar 03, 2010 | 2002 Chevrolet Express

3 Answers

Check engine light is on, diagnostic code p0140 keeps comming up.

I had this problem with my 05 Trailblazer and it happened around 50k miles. The oxygen sensor needs to be replaced and the part costs about 90 bucks but atleast you will have you're check engine light off.

Dec 16, 2009 | 2005 Chevrolet TrailBlazer

1 Answer

Service Engine Soon Light Came On

mostly your thermostat . how is your engine heat ?

Jun 05, 2009 | 1998 Saturn SL

1 Answer

Lack of power when accelerating

You really should have a code check done. There are numerous items that can give you similar symptoms. Two places to look are the fuel filter (usually overlooked till they gum up, and the throttle position sensor (but test it first with an ohmeter. You will need a manual (vehicle specific ones are available at most larger parts stores and most of those stores also do code testing free)

May 27, 2009 | 2006 GMC Sierra

1 Answer

97 mercury villager van lost power and oil light came on

sounds like the oil pump went on it. if so the engine is done

May 27, 2009 | 1997 Mercury Villager

Not finding what you are looking for?
1999 Chevrolet Silverado 1500 Logo

Related Topics:

51 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts


Level 3 Expert

77169 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22265 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides