Question about 2003 Chevrolet Silverado 2500HD

2 Answers

I changed out the battery,& now it won't come up to full idel.

Posted by on

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Master
  • 2,272 Answers

Low voltage during engine start means there might not be enough electrical poop to actually accomplish all steps as commanded, which is where the problem arises. Once lost, the PCM will believe the IAC to be in a much farther open position than it actually is, so it sees no need to open further. Start-stall or no-start episodes follow

This would be a good time to reset your IAC step count. It can be done with a battery disconnect of about 30 seconds, which will occur automatically if you happen to replace the battery.

Roll the key on and wait 5 seconds before starting the engine. This gives the PCM time to relearn IAC step count without the complication of trying to keep the engine running. After five seconds, go ahead and crank the engine. It should start, flare and settle to a nice idle if the IAC motor and controls are in good shape. While it's rare for an IAC motor to give this type of trouble in my experience, your unit may be 6 years old now... and they do wear out. If the reset prodecure is ineffective... or it works for a little while and reverts to stalling... you may have a bad IAC motor. It's the 4-wire device on the back side of your throttle body, removed with a #25 Torx driver. Perform a relearn after installation.
If not effective, you need to clean the throttle body. I'd expect it to start and idle regardless of TB deposits, but cleaning deposit buildup from the throttle body blades and bore will restore minimum airflow lost over time and will help support idle control. Minimum airflow is basically a safety net for the idle system... something that supplies up to 70% of the air needed for idle control to take some of the load off the IAC controls.

Thanks. Keep updated for any more query. You can rate this solution and show your appreciation

Posted on Oct 09, 2010

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Chevrolet Master
  • 11,800 Answers

In that case the cables clamps make a bad contact to the plots of the battery - the voltage is too low and the injectors don't open wide enough.
Clean them out with some paper towels and wire wool.

Posted on Oct 09, 2010

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

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

Hi,
a 6ya expert 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 repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Transmission problems


When you disconnected battery, how long did you do it for?
Some times a reset can take over an hour with no battery.
Also look at removing your ECU fuses.

Mar 12, 2014 | Chevrolet 3500 Cars & Trucks

1 Answer

So I changed the oil in my friend car and she has really high mileage on it so I put 10W-30 in it for high mileage an now it won't start can you help me out please


I would suggest a full synthetic oil, next time & stay with 5W-30
That will be better on start up

I have no idea why it won't start after only changing the oil

I think that was just a coincidence

I just installed a new throttle body ,because the motor has
acted up for 7 months & unknown the battery was failing
as I was diagnosing some odd behaveour

I was using professional scan tool software & when that
went weird I saw the computer module & battery voltages
going down,key on,engine off. So strange things happen
with todays electronics. When your think your on your game
things go to the twylight zone

May 23, 2012 | 1997 Chevrolet Lumina

2 Answers

I'm having problems with my 2006 chevy trailblazer. The car is idling to fast then dropping. The codes are P0506 and p0014.


just change your t.p.s ( throttle position sensor) the codes are false codes when tps goes out and the engine struggles to keeps going this will cause codes to be sent that are not really prob.

Aug 05, 2011 | 2006 Chevrolet Trailblazer

1 Answer

8 hp mercury motor starts and idels works fine at


Sounds like you need to service your carb as the mainjet is probably partially blocked or you have a choke thats not opening properly or a blocked filter.

Sep 15, 2009 | 2003 Mercury Mariner

1 Answer

93 Isuzu 2.3 4 cyl. Bucks at low rpms


first check fuel system, check fuel filters, fuel preasure & flow, service IAC sensor (idle air control) or replace also sparc plugs & wires .

Jul 22, 2009 | 2005 Renault R5

2 Answers

Idle speed problem


weird must be a ecu problem

Jun 18, 2009 | 1997 Mitsubishi Galant

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

42 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

76691 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeffrey Turcotte
Jeffrey Turcotte

Level 3 Expert

8531 Answers

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

Answer questions

Manuals & User Guides

Loading...