Engine noob question

[Layed90]

Hey guys. Long time subscriber in the bagged/lowered thread. Just beginning to get hands on regarding the engine (350 5.7 1990 Sierra)

Question: I recently replaced the IAC valve because it had a rough idle. After replacing the new one, the engine tries to turn over but doesn't start. Any info on this?

Question 2: When putting my TBI back together, I snapped a piece that goes from the driver's side valve cover to the TBI's casing (round metal piece that fits over the intake) does anyone know what that's called? I need to replace it and I can't get the bottom piece out of the valve cover either.

Sorry for so many questions, but I figured I turn to you guys while I wait for my repair manual in the mail haha.

Thanks all in advance!

 

[skylark]

Do an iac plunger reset. I believe that you jumper terminals a and b of the aldl and turn the key on for 30 seconds then shut off the key and remove the jumper. The other piece is called a "choke collar".

 

[Layed90]

Thanks for the reply. So what is the "jumper" part exactly?

 

[great white]

Jumper is any piece of metal that will conduct. A paper clip is commonly used.

The concern is your IAC is bottomed out and will not allow the engine to get enough air around the throttle plates to start. Have you tried cracking the throttle just slightly and turning it over?

if the IAC is your problem, it should start but die when you let off the throttle.

 

[Layed90]

Ah, got it. So that's not my problem them because it's not even starting now. Just keeps cranking with no turn over.

 

[skylark]

Time for the basics. Do you have fuel at the injectors and spark at the plugs?

 

[Ruger_556]

Hey guys. Long time subscriber in the bagged/lowered thread. Just beginning to get hands on regarding the engine (350 5.7 1990 Sierra)

Question: I recently replaced the IAC valve because it had a rough idle. After replacing the new one, the engine tries to turn over but doesn't start. Any info on this?

Question 2: When putting my TBI back together, I snapped a piece that goes from the driver's side valve cover to the TBI's casing (round metal piece that fits over the intake) does anyone know what that's called? I need to replace it and I can't get the bottom piece out of the valve cover either.

Sorry for so many questions, but I figured I turn to you guys while I wait for my repair manual in the mail haha.

Thanks all in advance!

What do you mean by "tries to turn over" ? I think you might be out in left field here...

 

[Parentnoia]

What do you mean by "tries to turn over" ? I think you might be out in left field here...

I imagine he means it has a long crank time, similar to what I have minus the fact that I'm vortec and he's TBI.

 

[Layed90]

I imagine he means it has a long crank time, similar to what I have minus the fact that I'm vortec and he's TBI.

Long crank, yep. Guess I'll start with basics today.

 

[Layed90]

Anyone know what the hose is called coming from the driver side valve cover? It goes into the air cleaner adapter around the throttle body it seems. Noticed it was snapped and I figured i'd replace it