No fire to the plugs
Asked by Mark Jan 25, 2016 at 01:45 PM about the 2003 Chevrolet Tahoe RWD
Question type: Maintenance & Repair
I have an 03 Chevy tahoe 5.3 lt. Motor I
changed the fuel pressure regulator the
crankshaft position sensor , the fuel filter and all
the spark plugs and the truck won't stay start .it
will start one time a day and run till it gets to
running temperate then it will kill and not start
back till next day can u help me is it my fuel
pump
40 Answers
Need to check fuel pressure to see what is going on. Fuel pressure should be 56 to 63 lbs. Watch the gauge after pressure builds up to see if it bleeds down more than 5 lbs. in three minutes.
Also, have you checked for spark after it will not start back up?
Yes I have and still no fire I can't understand how after not being run for a day it will start right up no problems and run about 20 mins then die and won't start anymore
Could be the ignition coil. It could be tested at Auto Zone. But also check the fuel pressure.
Question if I have a bad fuel pump would it stop fire to spark plugs
Could it be camshaft sensor or ignition control module
I thought of the ignition control module, but I have stores to check and I did not see one listed for the Tahoe. Cam sensor is a possibility. You sure there is no spark after 20 min. run time? Need to check that fuel pressure tho.
Yes there is no spark after 20 mins it kills like it ran out of gas and will not start back I spent 4 hours on it yesterday after it killed and it would not start back
I will have to rent the gauge to check fuel pressure I did change tho fuel pressure regulator Saturday and it had fuel pressure I'm stumped now
See thats another thing. It is not recommended to replace just one item under the plenum. Injectors, spider lines, and regulator should be replaced as a unit. You are going to want to verify fuel pressure and do a bleed down test like I described in my first post. The spark thing, there is no ICM listed. And I gather there is no distributor cap and rotor? I don't see one listed for that either. So is that a coil on plug set-up? And do you have a code reader? That could tell us something. The no spark thing is heat related. An electrical component is breaking down when it gets warm. Thats why I say to have the coil tested also.
Yes all spark plugs have individual coil packs no code reader tho a local mechanic came and did but never showed me the codes just said it was the crankshaft sensor
So whats the game plan?
Rent the fuel pressure tester and see if I need another fuel pump get cam shaft sensor and coil wires and hope I get fire
I do believe you can have the coils tested at a Auto Zone or other parts stores. I'll be look for your results. Diagnostics is the key instead of throwing monies at it.
I can't keep it running long enough to get it to auto zone I don't think it will make it and even if I make it I won't be able to leave from there I will contact mechanic tomorrow and get the codes it showed all I know is he said it was three codes
I talked to my brother that was there with me and he said mechanic tested the coil packs with another computer I think it was called rocket starter or something like that and said the coils had fire but want getting to the plugs
Either weak coils, or bad wires. When you do have spark check and see what it looks like, should be a nice white,blue spark, not yellow, orange in color. Still like you to check the fuel pressures, as you had your fingers in there, good idea to verify. Don't want to fix one problem and still have issues.
I will get the pressure test machine Saturday when I'm off and I will also but new wires for coil packs and change the cam shaft sensor anyway just to put new parts since they are not that expensive I wanted to change everything but I really need it running also that is my only truck .I thank u for the advise it has been very helpful I will update everyone on results Saturday afternoon
Great, any questions and I am always here.
Well today I'm flipping a quarter on buying new coil wires or camshaft sensor and I was folded it could be my shut off valve cord that's making it stall out but do I even have that on a 03tahoe
My pressure fire fuel pump is 43lbs and the mechanic where my truck is said that it can run at the pressure he thanks it's the cam sensor killing the fire idk any ideas
43 lbs is not good for fuel pressure. So I gather you haven't gotten a gauge and checked. Go rent a gauge, you get your moneys back. Cam sensor or any sensor can be checked at Auto Zone. If the spark is white, it is good. If it is yellow orange it is weak.
That's Wat the gauge said 43lbs its at a shop they still can't find why it keeps killing after 10 mins
You have to start fixing what you know is bad otherwise anything else you think you may find might not be bad. Fuel pressure at 43 lbs, I'm surprised it even ran. Needs to be 56 to 63 lbs. Then a fuel bleed down test needs to be done to check the injectors, spider lines, and fuel regulator. All of this affects starting and running of the engine. Spark needs to be white, blueish. You start by verifying & fixing these things first.
The shop I have it keeps telling me it can run with pressure that low wants he thinks its the cam sensor killing truck wat do u think I have checked all wires mecganic says I'm not getting fire something killing the fire
And we checked injectors he said they good spider also is good the regulator is new just put on
Listen, nothing is gonna matter to me on the fuel system unless the test are done so we know for sure it is working the way it is suppose too. Sorry but 43 lbs is not good enough. The cam sensor yes, I can see that. But was the spark looked at? What color is it? White or yellow.
The mechanic shop its at they did the fuel pressure test it read 43lbs the spark was not looked at to my knowledge I will asky tomorrow when it opens the mechanic is basically telling me he don't know I wanna change fuel pump and cam sensor he told me not to change the fuel pump its not the problem
Well see, I think he's looking at the ignition first here, making sure there is no problems which is good, there very well could be something wrong there. But you do have a fuel issue. Just let him get to that. Don't bug him or piss him off. Not to your benefit. You and I don't need to be telling him what to do. I know what I say to be true, so just keep that in the back of your mind. When he is done, we'll go from there if need be.
Karla_2016 answered 7 years ago
I have 04 Chevy Tahoe just changed motor, harmonic balancer new plugs n wires etc, it turns over but not getting fire?
Karla, there is a coil for each cylinder. Check for spark from more than one spark plug wire. You may have some bad coils. Also check to see if the coils are getting power from the wiring harness. Other possible causes would be the crankshaft sensor, or the camshaft sensor. Check wiring.
Michelle Rex. I have a 04 yukon denali xl ig has done something other guy truck did run 20 minutes an shuts down I changed everything cam an crank sensor new battery 3 different feul pumps cleaned mass airflow senor. But when stop watch hits 20 minutes it shuts off. What about throttle body could that be a issue Billy jackson in south Carolina
2003 Suburban > new crank sensor > new coils > new ecm > new plug wires> new cam shaft sensor > new ignition switch : Still NO Spark.
Grounding issue. Ground the black wire connecting in the white plug on the valve covers that is between the two inner coils on the drivers side and call it a day.
I'm having a problem with my 2004 Chevy z 71 5 3. I'm getting power and spark to 5 of my coils and spark plugs swap The coil packs around to see if it was a coil pack and it's not it's still rain off 5 cylinders So 3 of my coil and spark plugs are not getting spark I also had a meter and check to see if I was getting power to the plug that plugs into the Coil packs and I am. New spark plugs spark plug Wires. Brand new motor. The only thing I could think of is a computer issue
Derrickpickett1984 answered 5 years ago
Hi i need a answer rite quick ok i have a 2004 tahoe i was told i one of my sparks plugs was. Bad a few months ago so i kept driving it till today when i was driving it felt like i ran out of gas and shut off then some one came and look at it said the gas was low we killed the the battery so we got a boost and put gas it started up i drove it for like 25 -35 mins and soon when i was about to turn the corner by my house it shut down on me again and it did not go dead dead but i still got a boost did not started it waited 30 mins and it crank up again
GuruLWYBD was bang on - no ground getting to white plug between the two centre coil packs. Checked Bank 2 - had ground. Bank 1 - no ground. Grounded the wire wo stud on firewall and boom. Called it a day! Thanks a bunch - would love to know where the break in ground is - maybe search for it another day. Thanks again!