94 Chevy Truck fuel problems

On Feb 21, 1:58 am, "jdpolk" wrote:
> My 94 Chevy truck won't start after it was parked for a couple of months. I
> went out and started it once a week to keep the battery up, but one week the
> battery was low and wouldn't start. I put my battery charger on for a couple
> of hours at 2 amps. The motor turns over fine, but fuel isn't coming out of
> the injectors. I can pour gas down the TB unit and the motor will run until
> the fuel burns off. I just put in a new pump, strainer, and fuel filter. I
> checked the relay and fuse, Both are good. I can hear the pump running in
> the tank. I have checked for trouble codes. I got a 66,67,81,& 82. They are
> transmission codes. The old gas filter was not stopped up.
> Any ideas what I need to check and test ?

Check your fuel pressure at the TBI if you can get ahold of a test
gauge. If it's good, your injectors may be gummed up from sitting and
not opening when they should. One other thing that may be causing the
problem is if your ECM doen't know the engine is turning and will not
deliver fuel. The ECM recieves this information through the ignition
module in the distributor.
 >> Stay informed about: 94 Chevy Truck fuel problems 

"BurbGuy" wrote in message

> On Feb 21, 1:58 am, "jdpolk" wrote:
>> My 94 Chevy truck won't start after it was parked for a couple of months.
>> I
>> went out and started it once a week to keep the battery up, but one week
>> the
>> battery was low and wouldn't start. I put my battery charger on for a
>> couple
>> of hours at 2 amps. The motor turns over fine, but fuel isn't coming out
>> of
>> the injectors. I can pour gas down the TB unit and the motor will run
>> until
>> the fuel burns off. I just put in a new pump, strainer, and fuel filter.
>> I
>> checked the relay and fuse, Both are good. I can hear the pump running in
>> the tank. I have checked for trouble codes. I got a 66,67,81,& 82. They
>> are
>> transmission codes. The old gas filter was not stopped up.
>> Any ideas what I need to check and test ?
>
> Check your fuel pressure at the TBI if you can get ahold of a test
> gauge. If it's good, your injectors may be gummed up from sitting and
> not opening when they should. One other thing that may be causing the
> problem is if your ECM doen't know the engine is turning and will not
> deliver fuel. The ECM recieves this information through the ignition
> module in the distributor.
>
So, Is that a two part ignition module? One to run the engine and the second
to feed the ECM info. ?
 >> Stay informed about: 94 Chevy Truck fuel problems 

"jdpolk" wrote in message

>
> "BurbGuy" wrote in message
>
>> On Feb 21, 1:58 am, "jdpolk" wrote:
>>> My 94 Chevy truck won't start after it was parked for a couple of
>>> months. I
>>> went out and started it once a week to keep the battery up, but one week
>>> the
>>> battery was low and wouldn't start. I put my battery charger on for a
>>> couple
>>> of hours at 2 amps. The motor turns over fine, but fuel isn't coming out
>>> of
>>> the injectors. I can pour gas down the TB unit and the motor will run
>>> until
>>> the fuel burns off. I just put in a new pump, strainer, and fuel filter.
>>> I
>>> checked the relay and fuse, Both are good. I can hear the pump running
>>> in
>>> the tank. I have checked for trouble codes. I got a 66,67,81,& 82. They
>>> are
>>> transmission codes. The old gas filter was not stopped up.
>>> Any ideas what I need to check and test ?
>>
>> Check your fuel pressure at the TBI if you can get ahold of a test
>> gauge. If it's good, your injectors may be gummed up from sitting and
>> not opening when they should. One other thing that may be causing the
>> problem is if your ECM doen't know the engine is turning and will not
>> deliver fuel. The ECM recieves this information through the ignition
>> module in the distributor.
>>
> So, Is that a two part ignition module? One to run the engine and the
> second to feed the ECM info. ?

There are conditions when timing advance is controlled by the Ignition
Module but otherwise the ECM. Either way, the ECM must recieve reference
pulses from the distributor.
>
 >> Stay informed about: 94 Chevy Truck fuel problems 

"jdpolk" wrote in


> My 94 Chevy truck won't start after it was parked for a couple of
> months. I went out and started it once a week to keep the battery up,
> but one week the battery was low and wouldn't start. I put my battery
> charger on for a couple of hours at 2 amps. The motor turns over fine,
> but fuel isn't coming out of the injectors. I can pour gas down the TB
> unit and the motor will run until the fuel burns off. I just put in a
> new pump, strainer, and fuel filter. I checked the relay and fuse,
> Both are good. I can hear the pump running in the tank. I have checked
> for trouble codes. I got a 66,67,81,& 82. They are transmission codes.
> The old gas filter was not stopped up. Any ideas what I need to check
> and test ?
>

are the injectors pulsing?............kjun
 >> Stay informed about: 94 Chevy Truck fuel problems 

>> My 94 Chevy truck won't start after it was parked for a couple of
>> months. I went out and started it once a week to keep the battery up,
>> but one week the battery was low and wouldn't start. I put my battery
>> charger on for a couple of hours at 2 amps. The motor turns over fine,
>> but fuel isn't coming out of the injectors. I can pour gas down the TB
>> unit and the motor will run until the fuel burns off. I just put in a
>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>> Both are good. I can hear the pump running in the tank. I have checked
>> for trouble codes. I got a 66,67,81,& 82. They are transmission codes.
>> The old gas filter was not stopped up. Any ideas what I need to check
>> and test ?
>>
>
> are the injectors pulsing?............kjun

There isn't any fuel coming out of the injectors. I can manually pop the
injectors, but the ECM isn't sending them the signal to open.
 >> Stay informed about: 94 Chevy Truck fuel problems 

"jdpolk" wrote in message

>
>>> My 94 Chevy truck won't start after it was parked for a couple of
>>> months. I went out and started it once a week to keep the battery up,
>>> but one week the battery was low and wouldn't start. I put my battery
>>> charger on for a couple of hours at 2 amps. The motor turns over fine,
>>> but fuel isn't coming out of the injectors. I can pour gas down the TB
>>> unit and the motor will run until the fuel burns off. I just put in a
>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>>> Both are good. I can hear the pump running in the tank. I have checked
>>> for trouble codes. I got a 66,67,81,& 82. They are transmission codes.
>>> The old gas filter was not stopped up. Any ideas what I need to check
>>> and test ?
>>>
>>
>> are the injectors pulsing?............kjun
>
> There isn't any fuel coming out of the injectors. I can manually pop the
> injectors, but the ECM isn't sending them the signal to open.

You need to check for spark with a timing light or spark tester.

If gone or erratic....perhaps an ignition module.

skimmer
 >> Stay informed about: 94 Chevy Truck fuel problems 

.. I can pour gas down the TB
>>>> unit and the motor will run until the fuel burns off. I just put in a
>>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>>>> Both are good. I can hear the pump running in the tank.

>
> You need to check for spark with a timing light or spark tester.
>
> If gone or erratic....perhaps an ignition module.
>
> skimmer
>
>
I'm guessing that if the truck runs with gas poured down the TBI, that it
rules out mosy ignition issues. If the pump runs, and the filter's clear, I
would CAREFULLY crack lines both at the outlet of the filter and at the TBI
, one at a time, then turn the key on, and check to see fuel being
delivered, if the fuel is up to the TBI, then it's an injector issue or clog
between the fuel inlet and the injectors.As one of the other posters asked,
how old is the fuel? Old fuel will gum up after time, and will block small
passages, like injector tips.
Did I mention CAREFUL? please don't burn down your truck.

Ed
 >> Stay informed about: 94 Chevy Truck fuel problems 

On Feb 25, 3:29 pm, "jdpolk" wrote:
> "Ed White" wrote in message
>
>
>
>
>
>
>
> > . I can pour gas down the TB
> >>>>> unit and the motor will run until the fuel burns off. I just put in a
> >>>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
> >>>>> Both are good. I can hear the pump running in the tank.
>
> >> You need to check for spark with a timing light or spark tester.
>
> >> If gone or erratic....perhaps an ignition module.
>
> >> skimmer
>
> > I'm guessing that if the truck runs with gas poured down the TBI, that it
> > rules out mosy ignition issues. If the pump runs, and the filter's clear,
> > I would CAREFULLY crack lines both at the outlet of the filter and at the
> > TBI , one at a time, then turn the key on, and check to see fuel being
> > delivered, if the fuel is up to the TBI, then it's an injector issue or
> > clog between the fuel inlet and the injectors.As one of the other posters
> > asked, how old is the fuel? Old fuel will gum up after time, and will
> > block small passages, like injector tips.
> > Did I mention CAREFUL? please don't burn down your truck.
>
> > Ed
>
> That is on my next "to try" list. I think a 20oz drink bottle and a piece of
> fuel hose put over the fuel outlet should catch most of the fuel.
> I'm sure that it is time for a TBI rebuild or what ever is done to them.- Hide quoted text -
>
> - Show quoted text -

Likely not a bad idea to rebuild the TBI. If you know that the ECM is
not pulsing the injectors (remember the ECM grounds the injectors, the
injectors have 12volts at them any time the ignition is "on") take
the ignition module out of the distributor and have it checked. You
need a special tester to do this, a GM dealer should have one. If you
want just change the module, they're less than a hundred dollars for
one. I had the same problem with my truck two months ago and that's
what the problem was, after the new module, everything has been fine.
 >> Stay informed about: 94 Chevy Truck fuel problems 

"Ed White" wrote in message

>
> . I can pour gas down the TB
>>>>> unit and the motor will run until the fuel burns off. I just put in a
>>>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>>>>> Both are good. I can hear the pump running in the tank.
>
>>
>> You need to check for spark with a timing light or spark tester.
>>
>> If gone or erratic....perhaps an ignition module.
>>
>> skimmer
>>
>>
> I'm guessing that if the truck runs with gas poured down the TBI, that it
> rules out mosy ignition issues. If the pump runs, and the filter's clear,
> I would CAREFULLY crack lines both at the outlet of the filter and at the
> TBI , one at a time, then turn the key on, and check to see fuel being
> delivered, if the fuel is up to the TBI, then it's an injector issue or
> clog between the fuel inlet and the injectors.As one of the other posters
> asked, how old is the fuel? Old fuel will gum up after time, and will
> block small passages, like injector tips.
> Did I mention CAREFUL? please don't burn down your truck.
>
> Ed
That is on my next "to try" list. I think a 20oz drink bottle and a piece of
fuel hose put over the fuel outlet should catch most of the fuel.
I'm sure that it is time for a TBI rebuild or what ever is done to them.
 >> Stay informed about: 94 Chevy Truck fuel problems 

jdpolk wrote:

>
>>> My 94 Chevy truck won't start after it was parked for a couple of
>>> months. I went out and started it once a week to keep the battery up,
>>> but one week the battery was low and wouldn't start. I put my battery
>>> charger on for a couple of hours at 2 amps. The motor turns over fine,
>>> but fuel isn't coming out of the injectors. I can pour gas down the TB
>>> unit and the motor will run until the fuel burns off. I just put in a
>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>>> Both are good. I can hear the pump running in the tank. I have checked
>>> for trouble codes. I got a 66,67,81,& 82. They are transmission codes.
>>> The old gas filter was not stopped up. Any ideas what I need to check
>>> and test ?
>>>
>>
>> are the injectors pulsing?............kjun
>
>
> There isn't any fuel coming out of the injectors. I can manually pop the
> injectors, but the ECM isn't sending them the signal to open.

This sounds like the ECM isn't receiving pulses from the ignition module
due to either a bad ignition module or broken connection between the
module and the ECM. Without these pulses, the ECM will not pulse the
injectors or take over the timing.
 >> Stay informed about: 94 Chevy Truck fuel problems 

"Ed White" wrote in message

>
> . I can pour gas down the TB
>>>>> unit and the motor will run until the fuel burns off. I just put in a
>>>>> new pump, strainer, and fuel filter. I checked the relay and fuse,
>>>>> Both are good. I can hear the pump running in the tank.
>
>>
>> You need to check for spark with a timing light or spark tester.
>>
>> If gone or erratic....perhaps an ignition module.
>>
>> skimmer
>>
>>
> I'm guessing that if the truck runs with gas poured down the TBI, that it
> rules out mosy ignition issues. If the pump runs, and the filter's clear,
> I would CAREFULLY crack lines both at the outlet of the filter and at the
> TBI , one at a time, then turn the key on, and check to see fuel being
> delivered, if the fuel is up to the TBI, then it's an injector issue or
> clog between the fuel inlet and the injectors.As one of the other posters
> asked, how old is the fuel? Old fuel will gum up after time, and will
> block small passages, like injector tips.
> Did I mention CAREFUL? please don't burn down your truck.
>
> Ed
>

Ed..with all due respect you could be right on this but that was not the
case with my 93 and some others who have posted in this thread. My engine
would crank and crank with no fuel pulses and crazy flashes on the timing
light. During the crank mode (less than 400 rpm) the advance etc is
controlled by the ignition module not the ECM. If I sprayed some ether in
and could catch just of few fires in a row to kick it around it would run.
So I suspect (BUT DON"T KNOW FOR SURE) that the low rpm portion of the
module is out....if not the entire thing. If he is not getting PERFECT spark
when cranking, he should change it. If is getting perfect spark, he should
NOID light the injectors and test the pump.

skimmer
 >> Stay informed about: 94 Chevy Truck fuel problems