need help again

Ok. I’m going nuts here. My 94 s-10 blazer 4.3 w has been stalling and wanting to die like it had a vacuum leak so while looking for the leak I found a broken bolt on the intake platinum so I figured while I had the thing off I would replace the gasket. I did that and the truck started and died thin it did it again and now will not start at all. I found a vacuum hose on the manifold that was burnt so I repaired it .it went under the battery and back to the transmission some where .I know I am getting spark and I have 50 – 63 lbs of fuel pressure. Also about 6 months ago I installed a new fuel pump, nut kit, fuel filter, injectors and tps. Also if I let it set over night and try to start it, it will fire for a split second but will not try again .the stalling problem has been going on for a while now and there has never been a trouble code and there in none stored. Any and all help will be appreciated since I cannot afford to take it to a mechanic and really need to get it running thanks.

The vacuum line you speak of goes to the vacuum motor under the battery to engage the front differential when you select 4WD. There should not be a vacuum leak here unless the selector switch on the xfer case is bad.

On a 94 with CPI your pressure looks high. If you let the vehicle sit, does it leak down?

Since you have a fuel pressure guage, perhaps you have a vacuum guage? Did you try to measure it when it would run?

I'm not quite sure which gasket you replaced? Was it just the plenum or the intake? No matter what, if you remove either or both, you always install new gaskets. Hell, you could have a leak at the intake to the head?

Could you clarify which gaskets and the reason you changed them?

I didn’t have a vacuum gage and the gasket I replaced was the upper Pentium gasket I replaced it because I had to take it off to remove the broken bolt I found .The fuel pressure will bleed down a little but will go up to 60 lbs when the pump primers up. Was wondering would a vacuum leak keep it from starting altogether?

Ok, you removed the PLENUM to repair a broken bolt. You fixed the bolt, installed a new gasket and installed the plenum back on?

Is this when the problem started?

If it is, you should seriously recheck your work. An engine can start with a vacuum leak but will run poorly at idle if at all.

Does it start if you hold the pedal down?

Does not start at all the problems have been on going for a while now but I can’t find any thing wrong with what I have done (yet). Was wondering how I can check to see if the computer is telling the injector to fire? I know I have a plug in front of the intake is there a way I can tell? I do believe it is the injectors not firing. It may all be a coincident that it stopped starting when it did or I may have messed it up. I would rather not pull the intake unless I have to.

Where did you check your spark? At the plug or the coil?

Will the engine run on ether?

Can you borrow a scanner to do some diagnostics?

at the plugs whith a timming light

at the plugs whith a timming light
i am getting some starting fluid after work i didnt have any at the houseand i have a little scan tool but it is not showing any codes

Ok I went out there today and tried to start it and it would not start so I went to town and got some starting fluid. When I got Home I took the breather off and unhooked the sender on the intake hose (right in front of the intake) then got my wife to come out and turn it over and before I could aim the starting fluid at the intake it started right up and now I cannot get it to stop starting again .ANY IDEA WHAT IT COULD OF BEEN?

What are you talking about when you say "the sender on the intake hose"?

If you meant to say sensor, that was the intake air temperature sensor. It will not cause a no start condition.

1.) Have you ever replaced the cap and rotor?
2.) Have you replaced the fuel filter?
3.) How clean is the air filter?
4.) Have you removed and cleaned the EGR valve and reinstalled it with a new gasket?
5.) Does the engine usually die when the engine is hot?

What are you talking about when you say "the sender on the intake hose"?

If you meant to say sensor, that was the intake air temperature sensor. It will not cause a no start condition.

1.) Have you ever replaced the cap and rotor?
2.) Have you replaced the fuel filter?
3.) How clean is the air filter?
4.) Have you removed and cleaned the EGR valve and reinstalled it with a new gasket?
5.) Does the engine usually die when the engine is hot?


All this has been done in the last month and so far it is running good sense it started but will die after idling for a few minutes but will run good going down the road

Ah, replace you PCV valve and remove and clean your IAC valve.

My gf just had a stalling problem and it was caused by a carboned up IAC. Cleaned and scrubbed it with a toothbrush soaked with throttle body cleaner, rinsed it with the cleaner, scrubbed and rinsed the whole it was in thoroughly, reinstalled and it has been perfect ever since.

It will run rough for about 30 seconds while it is burning off the TB cleaner then it will idle smooth as a baby's bottom.

Ah, replace you PCV valve and remove and clean your IAC valve.

My gf just had a stalling problem and it was caused by a carboned up IAC. Cleaned and scrubbed it with a toothbrush soaked with throttle body cleaner, rinsed it with the cleaner, scrubbed and rinsed the whole it was in thoroughly, reinstalled and it has been perfect ever since.

It will run rough for about 30 seconds while it is burning off the TB cleaner then it will idle smooth as a baby's bottom.


what is the iac ?

IAC Valve = Idle Air Control Valve

Here it is for you:

http://www.tweaknews.net/decarbon/IAC.JPG

You will need a torx bit to remove the screws holding it in place. Also, becareful not to rip the O ring.

IAC Valve = Idle Air Control Valve

Here it is for you:

http://www.tweaknews.net/decarbon/IAC.JPG

You will need a torx bit to remove the screws holding it in place. Also, becareful not to rip the O ring.


ok thanks a lot and i hope it works if not i think i will have to go whith the gas and match methed.

hehe, no problem.

Tried cleaning and it did run better for a little bit but then it died again and when I started it back up it would run for a minute and die again it rally sounds like it is flooding? Can any thing make it do that?

Time to pull your upper plenum cover and check for washing.

Here is some information here:

http://www.s10forum.com/forum/showthread.php?t=113559&highlight=cpi+replacement

i will pull it again ,i just replaced the injecters and nut kit but it could still be leaking some where thanks for all the info its nice to talk to some one that has gone through it before

Just an up date I finely got tiered of looking at it in the garage and took it to an auto electric mechanic to look at and they found a bad wire in a connecter plug. Cost $100.00 but well worth it I was ready to light a mach thanks for all the help

connector plug to what?