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Honky
05-17-2011, 11:45 AM
So I’m trying to figure out why my engine is running poopy…

When I first start the truck it will run and drive normal. Lots of power and there are no issues. The problem starts when I shut it off and re-start and it doesn’t matter if it’s hot or cold. When I shut off the motor and re-start I have to put my foot to the floor to get it to start. When it does start it runs like it’s only running on 6 cylinders and runs very rich. At idle if I just tap the gas it will stall and then computer tries to fight to keep it going. If I leave it off for about an hour and re-start it will again run fine.


If I’m on the right track I’m thinking that my injectors are leaking, a bad pressure regulator, or the fuel pump is going bad

Any thoughts?

The engine is a Chevy 350 vortec out of 1997 Van

England
05-17-2011, 11:47 AM
yer bro sold you his lemon

Jeepnut
05-17-2011, 11:58 AM
there a sucker born every minute;)

toyon35s
05-17-2011, 12:00 PM
sounds like a semi clogged fuel filter ,the pumps just go the dont act like there going ,my honda did the same thing ,i put in 20bucks premium plus octaine boost and rat bagged it for a few hours now it runs fine :dontknow:

epic3
05-17-2011, 12:06 PM
Does it stall have the diagnostic port? Scan it before jumping to any conclusions.
Is it multi port or throttle body injected?

Honky
05-17-2011, 12:09 PM
yes it does have a scan port. the problem is I can't drive it to get it scanned.

epic3
05-17-2011, 12:10 PM
yes it does have a scan port. the problem is I can't drive it to get it scanned.

Does it still have a check engine light? If so you can run a jumper in the scan port and count the flashes on the check engine light

Honky
05-17-2011, 12:17 PM
No on the check engine light

epic3
05-17-2011, 12:19 PM
hmmmm you may be able to use a test light to do the same thing.
But back to one of my original questions is it Multi port or TBI injected?

dirka dave
05-17-2011, 12:23 PM
Just too damm busy getting ready for my may long adventure.
Otherwise I would be able to spend an evening pokeing around on it.

Honky
05-17-2011, 12:23 PM
yeah multi port

one more thing...when the pump primes and also after the key is shut off I can hear a popping sound from the centre of the engine.

could be fuel leaking or pressure not holding?????:dontknow:

85chevy
05-17-2011, 12:34 PM
Almost sounds like ur getting to much fuel maybe a bad sensor telling it to over fuel when its warm?? perhaps the coolant sensor maybe even a bad injector have u pulled the plugs to see if one is covered in fuel?

Jeepnut
05-17-2011, 12:49 PM
Does it still have a check engine light? If so you can run a jumper in the scan port and count the flashes on the check engine light


There is no engine check light on this truck

epic3
05-17-2011, 12:54 PM
Well one easy way to diagnose if its leaking injectors, in the mornin or when its cold and it generally fires up with no probs just turn the ignition on and wait for a few minutes. With the fuel system under pressure but the engine not running if the injectors are leaking then they will do so now. It should run rough like you originally posted after a restart. If so unbolt the fuel rails and gently lift them away from the manifold with the injectors in place being careful not to loose the injector o rings and do the same thing over again and visually inspect them to see if they are dribbling like you after a long night in front of the fire.
If any are leaking you can have them rebuilt or just replace them with new ones.

Honky
05-17-2011, 01:59 PM
Thanks Phil...I'll give that a try tonight

atoyot
05-17-2011, 02:07 PM
jeepthing??????.
.
.
.
.
.

epic3
05-17-2011, 02:37 PM
I think this would actually be a chevy thing

if it was a jeep thing he'd already have been through it a dozen times and known the fix

I'll be at the shop late tonight Kev if you need to call for help

4skin
05-17-2011, 08:36 PM
jeeps confuseing the chebby parts

dirka dave
05-17-2011, 09:14 PM
Pull the plugs and see if one is soaked in fuel.


Also check if one is white, burning lean.

Bigd74
05-17-2011, 09:27 PM
Does it have a mass airflow sensor? I hold an Iroc that did the same sort of thing when the sensor was bad.If it has one try disconnect it and see what happens.

Cyanide
05-17-2011, 09:33 PM
i had the same problem in my blazer turns out it was one of the two fuel injectors staying open and pissing out fuel to the engine causing it to stall, it was a green wire that was broken that was hooked up to the fuel injector, the green wire was located underneath the air filter but I have TBI not multi port so this whole message will be useless

mus-Tard
05-17-2011, 10:40 PM
l have a scan tool that could probly pull any codes for you. l could maby run it over tomarow night if thats alright.


see whats up.

Chopstick
05-18-2011, 12:14 AM
l have a scan tool that could probly pull any codes for you. l could maby run it over tomarow night if thats alright.


see whats up.

we already tried that

4skin
05-18-2011, 12:30 AM
what kind of scan tool cambodian tire type
baisicaly a code reader
or a real scan tool that will give you sensor readings
in real time

mus-Tard
05-18-2011, 12:34 AM
l have a good one that does live data

4skin
05-18-2011, 01:48 AM
l have a good one that does live data
oh but do you know how to read it:dontknow:




















































































[f] [15] [15] [15] [15] [15] [15] [15] [15] [15]

96_z71
05-18-2011, 03:05 AM
If its a 97 vortec it has the internal injectors off the 'spider' injection system which is inside the intake manifold. I think they're little poppet injectors. At least thats what my 96 350 Vortec has. Kind of a dumb multi-port setup. Sounds like a fuel pressure issue to me, not sure about the vans but in trucks the fuel pumps always go. My trucks on its 4th i think, but with 402xxx kms.

Always broke
05-18-2011, 07:25 AM
I have a snap on scan tool if you want to borrow it Kevin , sounds like one of the sensors to me telling it to over fuel either o2 or temp sensor.

pumpkin
05-18-2011, 07:50 AM
I love all the guessing. Its a vortec, so it is OBD II. You have to us a scanner to get codes. First place to start is with a fuel preasure gauge. Make sure you have the proper preasure, and that it is holding preasure. If that is ok then proceed to check codes. Vortecs are known for the plastic injector fuel lines leaking inside the intake.


K and i'll through out a useless guess,,,, stuck open EGR

Chopstick
05-18-2011, 01:49 PM
what was weird was when i hooked my scanner up an was lookin at the live feed or monitors, the o2 sensors weren't turning on but everything else was workin properly?

plastic fuel lines? that sounds gay!!

Honky
05-18-2011, 01:55 PM
The codes were coming up for error's for an auto....which is strange


something about not going into a closed loop

Pressure gauge is the next step


and I do hear a gurgling coming from somewhere top center of the engine as soon as I turn the pump on


Hey Epic...i did what you said and left the key on for about 15 min and then cycled the key (pump) on and off a bunch of times....but there was no change...still fires right up but again as soon as I try and restart...bad things happen

epic3
05-18-2011, 02:05 PM
The codes were coming up for error's for an auto....which is strange


something about not going into a closed loop

Pressure gauge is the next step


and I do hear a gurgling coming from somewhere top center of the engine as soon as I turn the pump on


Hey Epic...i did what you said and left the key on for about 15 min and then cycled the key (pump) on and off a bunch of times....but there was no change...still fires right up but again as soon as I try and restart...bad things happen

Then I doubt that you have leaking injectors or fuel lines.

Honky
05-18-2011, 02:10 PM
Jeepnut said the code coming up error's for that auto trans is possibly the pluse generator that the speedo goes into that may have come loose.

epic3
05-18-2011, 02:50 PM
The gurgling may just be the fuel rail/lines pressurizing which is normal. Your not auto, when the motor was swapped in wouldn't it have been done with a standard ecu and harness?
Or did geriatric jeepnuts originally have an auto in it?

Honky
05-18-2011, 02:58 PM
The motor was out of a 3500 van auto...he said he has to get the computer sent down to the U.S. to re-programed and the pulse generator is to fool the computer?????

dirka dave
05-18-2011, 03:03 PM
This thread sucks without boobies.

Honky
05-18-2011, 03:41 PM
http://i814.photobucket.com/albums/zz62/Stampede_55/gif/tnz93gf1na.gif

Chopstick
05-18-2011, 05:44 PM
[36] [36] [36]

ROBO
05-18-2011, 05:45 PM
if its open loop .. theres a bad sensor some were....get the scanner on it and some one who can read it. ill be buy tomorow night

Ironman
05-18-2011, 05:58 PM
your cogburn cog isnt working with your spacely sprocket properly

Toyquad
05-18-2011, 07:24 PM
check you diesel exhuast fluid

dirka dave
05-18-2011, 10:40 PM
All good.

It was the chrome plated muffler bearings, piston return spring and the flux capicator.

Thanks for your help Rob.

Ironman
05-18-2011, 11:13 PM
Halogen fluid? How about the angle of the dangle? Did you think it might be the way its sitting on the curvature of the earth?

Apathy
05-19-2011, 06:18 AM
All good.

It was the chrome plated muffler bearings, piston return spring and the flux capicator.

Thanks for your help Rob.

so,, what eas it REALLY?

dirka dave
05-19-2011, 06:20 AM
REally....


It was a few things, Throttle position sensor, but the main culprate was.....



















































TEMPERATURE SENDING UNIT !!


(well actually the plug)

ROBO
05-19-2011, 07:33 AM
np glad i can help..hocky.. beers.. and wheelbarrow fire with exploding tiles!! and workin on junk!! fun night i must say!!....

Apathy
05-19-2011, 07:56 AM
np glad i can help..hocky.. beers.. and wheelbarrow fire with exploding tiles!! and workin on junk!! fun night i must say!!....

sounds like a winner to me!!!!!!!

dirka dave
05-19-2011, 08:50 AM
Forgot about the exploding things.

85chevy
05-19-2011, 09:53 AM
Wait so I was right???

Honky
05-19-2011, 11:38 AM
Thanks for all your help!!! The whoreJ will be beatin' on, on the trails this long weekend!!!!

beers are on me next fire guys[cheers]

Honky
05-19-2011, 11:41 AM
on another note..that was a fun night..with the hockey game on ..tunes...cooking over the wheelbarrow fire and working on da Jeep

I think this could start into shop nights for those that need a place to fix their junk!!!

epic3
05-19-2011, 03:48 PM
Wait so I was right???

you want a cookie, a pat on the back, some sort of recognition for your efforts?

Not here

85chevy
05-19-2011, 04:06 PM
nope just glad its fixed [cheers]

Honky
05-19-2011, 04:12 PM
I don't give a pat on the back.....but I did give Dirka a reach-a-round

Murd0c
05-19-2011, 11:46 PM
I don't give a pat on the back.....but I did give Dirka a reach-a-round
You could actually find it?