Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
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I will do my best to assist you. When you are finished please click on accept only if you are satisfied. I don't get paid unless you do.Please do not accept if you cannot leave positive feedback. I don't know if you are a tech or a just working on your own vehicle so we may have to fine tune the answer. I only know as much about your problem as you have told me in your post, so my answers will be based on what you tell me so please add all the details you can.
so how can I check to see if it has jumped time how do I check it I cant get to the distributore
if it has jumped time will I get a code on the trucks computore?
These don't use a distributor, they use a coil pack system.
what is that
Try this first, does it try to start or stumble if you put a bittt of fuel directly into the throttle body?
OK, then that is not ignition, that is fuel. What is your fuel pressure?
no idea I replaced the fuel filter is there something else I can check?
could it be the fuel pressure sensore curcuit
Yes the fuel pressure. First, see if the fuel pump runs.
There is no fuel pressure sensor.
how do I check that
See if you can hear the fuel pump when you first turn the key on, it shoudl run 2 seconds.
yes I hear it
Did the sound change at all?
Ok, test the pressure and see. Also see if there is spark at the any of the spark plugs.
we have spark how do I check the pressure
You will need a fuel pressure gauge and the adapter hose to install into the system.
we dont have one is there any other way. Aslo this truck has 170000 miles and the original timing belt could it have jumped time and how do I check that?
I doubt the timing at the moment and it is a chain not a belt.
is there any other way to check the fuel pressure
No, it must be done with a gauge.
if its low what do I do
Replace the fuel pump.
where is it locaTED
In the fuel tank
my computer shows a code of PO 452 what is that
That is the EVAP sensor on the top of the fuel tank, not part of the fuel supply system, but of the emissions.
whould that be the problem
No, because the pressure sensor is only for the evaprative emissions, the fuel vapors. It has nothing to do with the operation of the fuel pump. YOu can unplug that and all you would get is a code. tHe engine will still run fine.
we unhooked the fuel line at the filter and its pumping fuel fine
would a code of po 420 affect it
No that is a code for a bad converter. Even though fuel is coming out, can the pump give the proper pressure. 41-47 psi?
it shot fuel clean across the drive way'
Forgive me, but we need the actutal pressure. 20 psi will shoot across the drive way.
ok let me check it out
ok the pressure is at 38
its starts at 41 for a few secounds than drops to 38
Did it drop off past 38 after a few mins?
ok, is the security light flashing?
but there doesnt seem to be any fuel in the carb when we try to start it
IF security is active, it will not allow the injectors to run
it doesnt flash but it come on after a few secounds
does the check engine light remain on when cranking?
Ok, do you have any sort of scan tool/
for the computer
just one that checks the codes that I gave you earlier
OK, so a code reader?
Ok, we will need to see a real scan tool to see if the computer is stopping the injectors for some reason. It could even be the ignition module causing this.
can I bypass it some how
No, that is the problem. however most part stores can test the igntion module for free.
do I haveto take the vehical to them
or can I remove the ignition module and take it to them
No you can take the module off. It is under the coil packs in the passengers side of the engien?
the coil pack is what the spark plug wires go into instead of a distributor cap right
and what does it look like
Is is flat and the coils attach to it with screws.
There are a couple connectors on each side.
how do I get to it from under neith
yes that is the easiest. The bolts should be a 5.5mm./
ok I found it and some place that can test it if its bad and i replace it will that get it to start?
ok I found it and a place to test it if its bad and I replace it will it start? if its not bad whar else could it be?
OK, get it tested and see.
Possibly a bad wire or something in the PCM. I am trying to suggest parts to test that done need a scan tool or shop, but it may end up as that.
need help on a 1999 Chevy K3500 pickup with a 7.4 L