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GM Bob
GM Bob, ASE Master Technician
Category: GMC
Satisfied Customers: 1103
Experience:  30 plus years experience as GM technician, ASE Master Technician and GM Certified
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Gmc Sierra 1500: My truck will crank all day long but want

Customer Question

My truck will crank all day long but want start.the only code I'm getting is c0281 which is abs would this keep my truck from starting
Submitted: 2 years ago.
Category: GMC
Expert:  Gary replied 2 years ago.
Welcome! My name is ***** ***** I will do my best to assist you with this problem.
do you know what the fuel pressure is reading key ON engine OFF ?
have you done a compression test yet ?
taken a good fuel sample in a glass container and let the sample sit and look for any separation ?
Customer: replied 2 years ago.
I haven't done a pressure test cause I just assumed it should have at leas tried to start when I put starting fluid and I poured a little gas in it
Customer: replied 2 years ago.
I drove it for bout an hour stopped at gas station and it wouldn't start back up
Expert:  Gary replied 2 years ago.
are the spark plugs soaked with fuel ?
can you make sure the fuel is good ?
Customer: replied 2 years ago.
They was wet when I checked them a few days ago
Expert:  Gary replied 2 years ago.
ok if the fuel is good and it will not start by adding gas or starting fluid and you have confirmed spark at the spark plugs when cranking it over we need to check compression on this engine
if all 8 cylinders are over 125 PSI then at this point try a new crank sensor and see if it will start up
this engine just needs spark and fuel and compression to run
if it was getting too much fuel keeping the gas pedal floored it would start up at least for a little bit
Customer: replied 2 years ago.
If it was crank sensor then would my scanner read a code or would I even get spark if it was bad
Expert:  Gary replied 2 years ago.
with fuel and spark and if the compression is good at this point the engine is getting the spark at the wrong time
it really comes down to eliminating the 3 things the engine needs to run
fuel - you added fuel and confirmed fuel and did not run
compression - we need to check
spark - confirmed spark at the plugs but is the spark being sent at the correct time and a lot of times they will not set crank sensor codes for this
Customer: replied 2 years ago.
Ok so I need to get something to test compression and if that's good replace crank sensor
Expert:  Gary replied 2 years ago.
let me know how it goes
you can always get me back through this post any time with any follow up with this question even after you rate us here at Justanswer !
Customer: replied 2 years ago.
Ok compression is between 155and 165 I changed crank sensor and ignition coil what else could it be
Expert:  Gary replied 2 years ago.
lets see if another expert has any ideas
hang on another expert will reply back to you
Customer: replied 2 years ago.
I changed plugs and wires before my distributor was changed do u think maybe the plugs are bad th
Expert:  GM Bob replied 2 years ago.
Hello my name is***** you still need help?
Did you change the plugs?
How are you testing for spark?
Please let me know
Thank you
Customer: replied 2 years ago.
I changed plugs and wires before my distributor went bad I brought it to a shop so they could set the timing about 2 months ago I checked the spark with a screwdriver I pulled the cap off this morning and the rotor has a little play in it counter clockwise
Customer: replied 2 years ago.
The night that it wouldn't start I stopped at a red light and it had a little of a rough idol wasn't to bad though and then when I killed it it wouldn't start back up before that the check engine light would come on sometimes but not everytime
Expert:  GM Bob replied 2 years ago.
Are the plugs still gas fouled?
Have you tried to hold the gas pedal to the floor and try starting?
This shuts the injectors off. Called clear flood mode.
How low on fuel were you when you filled it up?
Do you know the code it was setting
Customer: replied 2 years ago.
Yes the plugs have gas on them and I have tryed holding the pedal down I had bout 1/8 of a tank I don't know what code it was setting it isn't setting any codes now
Customer: replied 2 years ago.
Could it be some sensor
Expert:  GM Bob replied 2 years ago.
Have checked the fuel?
Put it in a glass jar let sit. Should look clear
I don't know if you can do this. Pour some gas out and light it. If it just burns slow you my have bad gas.
Customer: replied 2 years ago.
Well I have tryed starting fluid and poured a little gas in the intake and nothing changed if it was bad gas wouldn't have at least tryed to start when I did that
Expert:  GM Bob replied 2 years ago.
it never hit on any cylinders when you add starting fluid?
Does the engine oil smell like gas?
Customer: replied 2 years ago.
Nothing happen when I done it oil looks and smells ok
Expert:  GM Bob replied 2 years ago.
If you pull the coil wire off at the coil and crank it over. Spark should jump off the post to the coil housing.
Make sure there is no gas around it
Customer: replied 2 years ago.
Well I just put a new coil on yesterday and crank sensor and had Icm checked
Expert:  GM Bob replied 2 years ago.
Ok
can you still test it?
Customer: replied 2 years ago.
No rite now I don't have anyone to help me I will later and let u know
Expert:  GM Bob replied 2 years ago.
Most time you can hear it jump.
Customer: replied 2 years ago.
What do u mean?dont I need someone to turn it over while I hold the wire close
Expert:  GM Bob replied 2 years ago.
No you don't need a wire. The spark will travel off the coil to the metal on the coil. about 1 1/2 inches should jump it
Remove the coil wire from the coil and crank it
Customer: replied 2 years ago.
Ok i pulled wire from coil and turned it over it made spark
Expert:  GM Bob replied 2 years ago.
Ok good
I think you need to pull the plugs out and blow the off and clean them.
Also with plugs out need to crank the engine over clean out the cylinders.
Most unplug the coil connectors to disable spark and unplug the connector for the injectors ( First )
Than plug coil back in and try starting it with starting fluid with the injectors unplugged
Customer: replied 2 years ago.
Ok I have the spider how do I unhook that
Expert:  GM Bob replied 2 years ago.
All you need to do is unplug the connector to the spider on top of the engine