Hard initial start then starts and runs good
ouwee
Because of the computer control hard starting could be a variety of things
The factory manual shows this order for my 1996
Sensor checks check the engine coolant sensor vs ambient air temp sensor if coolant temp is more than 5 degrees greater or less could cause the problem although it should set a code i would think
Check throttle position sensor for sticking also would probably set a code
Fuel checks
Check fuel pump relay should hear pump run for 2 seconds before you turn key to crank may have to listen at fuel fill while someone turns key on
Check fuel system pressure i had my system checked still held pressure over a weekend according to the shop, i want to get a pressure gage to to double check
Manual also lists other tests such as fuel injector balance test which i am not sure how to get done maybe dealer?
I cannot figure out the fittings that were shown in the sticky for testing at the filter was hoping someone here has a picture
Ignition, plugs, wires, distributor cap rotor check replace if worn
It would good to find a shop with a diagnostics approach
My shop is mainly parts swapper which i do not like
Also, be aware when swapping parts some after market parts could be worse than the original gm parts especially electrical and fuel. If you parts sway try using oem parts if possible
I have not figured out what is wrong with mine yet but i am going through the list and will replace parts as last resort.
Good luck with your blazer.
Because of the computer control hard starting could be a variety of things
The factory manual shows this order for my 1996
Sensor checks check the engine coolant sensor vs ambient air temp sensor if coolant temp is more than 5 degrees greater or less could cause the problem although it should set a code i would think
Check throttle position sensor for sticking also would probably set a code
Fuel checks
Check fuel pump relay should hear pump run for 2 seconds before you turn key to crank may have to listen at fuel fill while someone turns key on
Check fuel system pressure i had my system checked still held pressure over a weekend according to the shop, i want to get a pressure gage to to double check
Manual also lists other tests such as fuel injector balance test which i am not sure how to get done maybe dealer?
I cannot figure out the fittings that were shown in the sticky for testing at the filter was hoping someone here has a picture
Ignition, plugs, wires, distributor cap rotor check replace if worn
It would good to find a shop with a diagnostics approach
My shop is mainly parts swapper which i do not like
Also, be aware when swapping parts some after market parts could be worse than the original gm parts especially electrical and fuel. If you parts sway try using oem parts if possible
I have not figured out what is wrong with mine yet but i am going through the list and will replace parts as last resort.
Good luck with your blazer.
You are correct. Hard starting could be caused by a number of things.
After 30 years of experience with s-series vehicles, I was simply suggesting what I have seen as the most common cause.
Apparently Abraham Torres-Arredondo, the author of the series on Vortec trouble shooting agrees:
After 30 years of experience with s-series vehicles, I was simply suggesting what I have seen as the most common cause.
Apparently Abraham Torres-Arredondo, the author of the series on Vortec trouble shooting agrees:
Yes, let me repeat that one more time: As crazy as this sounds... the fuel pump will deliver enough fuel to keep the engine running, but not enough to start it when you're cranking the engine.... and this makes a lot of folks think that the problem lies anywhere else but in the fuel pump!
Last edited by oldeerslayer; Dec 19, 2017 at 09:57 AM.
Harbor freight sells a $20 fuel injection pump test kit that comes with rubber tube and clamps for testing at the filter. Mine and other members' has leaked at the gauge connection but some teflon tape on the threads seals it up.
Rusty thanks did you have a leak at the scrader port? if you tee in at the filter do you relieve the pressure 1 st. Have been intimidated by the fuel system because of high pressure, i used to check fuel pressure on my cars before the fuel injection system in the days of carbs and mechanical pumps.
You can relieve the fuel system pressure at the schrader port. I never have pressure when I remove the filter and/or fuel lines but you will get drainage so plan accordingly. Do your initial test at the port. If you have good pressures and no leak down at the port then testing at the filter won't tell you much. It would be needed to isolate the problem if the behavior at the port does not meet spec (pump vs injectors vs regulator).
George
George



