1989 Chevy 1500 2WD 350 auto, all stock, 140k miles.
2nd owner, bought from father-in-law 2-1/2 years ago, no trouble until
today. Suddenly from last time I drove it last week until today, it started
coughing/sputtering whenn under a load or climbing a hill. It gets worse
the more gas you give it, runs smooth at lite throttle or idle, this shows
up after warm, but runs better (it seems) when choked on cold start. I
really had to feather the gas pedal to get it home, but it idles just fine.
Happened suddenly after being parked for a week, then started and run 5
miles, then into store and back out, it started on return trip home.
Any suggestions on where to look? I'm thinking throttle body/injector, or
else fuel pump. Maybe fuel filter?
Thanks for any help.
Whitelightning - 14 Dec 2007 03:15 GMT
> 1989 Chevy 1500 2WD 350 auto, all stock, 140k miles.
>
[quoted text clipped - 12 lines]
>
> Thanks for any help.
I would check fuel pressure, and if fuel filter hasnt been changed in awhile
it can't hurt.
Whats the weather like where you are at? If its been cold and fuel level low
dont rule
out water in fuel. Keep in mind no choke on fuel injection. As it runs in
open loop ignoring sensors when cold which is richer than closed loop,
there could be a sensor acting up. What operating tempature is the engine
running? Any codes? Jump pins A and B with a paper clip and then turn key
on, engine off and read codes by counting blinks of the check engine light,
http://www.freeautomechanic.com/diagnostictroblecodes5.html has picture of
connector and pins to jump. another possablity if its been very cold is a
vacumm line split. If you leave the pins jumped with the engine running you
can tell if its going into closed loop when it warms up, the check engine
light will blink . The rate changes when it goes into closed loop which
should happen when the engine reaches about 180 degrees.
Whitelightning
JG2U - 14 Dec 2007 23:52 GMT
> I would check fuel pressure, and if fuel filter hasnt been changed in
> awhile it can't hurt.
[quoted text clipped - 13 lines]
>
> Whitelightning
Thanks... I'm in SC in the middle of our drought, no rain in 2 months.
Temps warm, in the 80's this week.
I'll pull the codes tomorrow, I didn't think about that. I'm used to
working on stuff too old to have a computer in them.
JG2U - 18 Dec 2007 12:38 GMT
>> I would check fuel pressure, and if fuel filter hasnt been changed in
>> awhile it can't hurt.
[quoted text clipped - 19 lines]
>I'll pull the codes tomorrow, I didn't think about that. I'm used to
>working on stuff too old to have a computer in them.
Well, no codes are stored. I'll know today if the new fuel filter and
fuel treatment works.
I did check it again... cold start and driving is good, it's only when
it gets warmed up that it starts bucking and cutting out under load or
when you stab it. It seems more ignition related to me, but I'm no
expert.
Meat Plow - 14 Dec 2007 17:00 GMT
> 1989 Chevy 1500 2WD 350 auto, all stock, 140k miles.
>
[quoted text clipped - 9 lines]
> Any suggestions on where to look? I'm thinking throttle body/injector, or
> else fuel pump. Maybe fuel filter?
Maybe moisture in your fuel. Try some dryer.
Troy Sigwing - 14 Dec 2007 19:26 GMT
bad cat
> 1989 Chevy 1500 2WD 350 auto, all stock, 140k miles.
>
[quoted text clipped - 12 lines]
>
> Thanks for any help.
KENG - 14 Dec 2007 23:10 GMT
> bad cat
>
[quoted text clipped - 14 lines]
>>
>>Thanks for any help.
I second the bad cat. Mileage and age are right for that.
KenG
JG2U - 14 Dec 2007 23:49 GMT
>> bad cat
>>
> I second the bad cat. Mileage and age are right for that.
> KenG
I hadn't even considered that... interesting. Is there a test for that,
other than disconnecting?
JG2U - 22 Dec 2007 15:16 GMT
Problem solved. It needed new distributer cap, rotor button and plug
wires. While I was under the hood I replaced the "carb" (TBI) base
gasket to resolve a fast idle issue as well.
Just whose brain-dead idea was it to put the dizzy in the back of the
motor crammed up against the firewall? sh.t-for-brains engineering...
Whitelightning - 23 Dec 2007 17:52 GMT
> Problem solved. It needed new distributer cap, rotor button and plug
> wires. While I was under the hood I replaced the "carb" (TBI) base
> gasket to resolve a fast idle issue as well.
>
> Just whose brain-dead idea was it to put the dizzy in the back of the
> motor crammed up against the firewall? sh.t-for-brains engineering...
It does a good job of staying dry back there, something brain dead dizzy
engineers who put them in the front of the engine dont consider on a truck.
Whitelightning
JG2U - 24 Dec 2007 15:40 GMT
>> Problem solved. It needed new distributer cap, rotor button and plug
>> wires. While I was under the hood I replaced the "carb" (TBI) base
[quoted text clipped - 7 lines]
>
>Whitelightning
Have owned and been around those front dizzy motors for years, and
have never had a wet one. Telling yourself it's in the back to help
keep it dry is a good strategy to keep from cussing it, though!
Merry Christmas!