Starting problem.

[Paul Higg]

It's right below the TPS!!

Junk, that photo with the green circle, is what is circled the TPS? In the photo isn't the IAC valve above the circle? And what exactly does TPS stand for?

 

[gmjunkie]

Junk, that photo with the green circle, is what is circled the TPS? In the photo isn't the IAC valve above the circle? And what exactly does TPS stand for?

Nope, the IAC is circled, that that is above the IAC that has the green through it is the TPS!!

IAC = Idle Air Control

TPS= Throttle Position Sensor

 

[Paul Higg]

Okay, thanks Junk, now do I spray cleaner in there?

Also, what is the thing above it that looks like a horizontal carb? Do I spray in it to clean it too? Sorry about being so dense.

 

[gmjunkie]

Red= TPS

Green=IAC

 

[Paul Higg]

ARRRGGHHH.

So now what does TPI stand for or did you make a typo and mean TPS? PLUS, do I remove them and clean them? And what about cleaning the horizontal carb thing above? How do I clean that? Do I use spray cleaner on all three. Please walk me through it Junk? I am a newbie on some of these parts.

 

[gmjunkie]

Okay, thanks Junk, now do I spray cleaner in there?

Also, what is the thing above it that looks like a horizontal carb?

Thats the Throttle body!! Remove the IAC,Can't remember exactly size around 1- 1 1/4 inch, Counterclockwise screws out!!! Put some rags under the throttle body below the IAC and OPEN throttle WIDE OPEN and spray Liberally the throttle plates and any orifices you can see in there!! There is going to be All sorts of Black Crud run out of the IAC hole,Spray it out good too!! Spray the pintail on the IAC till clean,Let it all dry out and put it back together!!!Be sure to put plenty of rags under it,You don't want cleaner running down into your Opti-Spark!!!

 

[Paul Higg]

So far so good. So what does TPI stand for or did you mean TPS?

Also, how do I open the throttle? Do I use my hand or do I need someone to press on the gas pedal. See, dumb questions but I need to be walked through it. Thanks again Junk!

 

[gmjunkie]

ARRRGGHHH.

So now what does TPI stand for or did you make a typo and mean TPS? PLUS, do I remove them and clean them? And what about cleaning the horizontal carb thing above? How do I clean that? Do I use spray cleaner on all three. Please walk me through it Junk? I am a newbie on some of these parts.

I made a BooBoo!!I meant TPS,And don't touch it,(But you will probly have to unplug it!!) Other than that Just leave it alone!! But Remove the IAC!!
PS I just hold the throttle open all the way by hand!!!

 

[Paul Higg]

THANKS Junk!!!!!!

You da Man!

 

[JAKE]

While you're at it check the plastic, one-way check valve on the psngr side of the intake - about midway. It has a rubber 90 degree fitting going to the intake and two fittings/hoses at the opposite end.

Last week when checking out the new 96 I just bought I found mine was brittle - from years of heat exposure - and broke when I touched it.

Bought another one at AutoZone; $4.xx

Jake

 

[cntrhub]

If it starts right up cold in the morning, where is the air leak? Where is the clogged part that is causing a hard start? Would not a clogged air cleaner run the engine rich in the warm start? That would mean fuel is getting to the cylinder? You had to push on the pedal to start on a hot day? Does that mean more air because you have to match the over rich condition?

How much over-rich is that on cold start-up where it works and starts fine. You might be chasing your tail is more the TPS on the throttle app. I doubt it since it starts so well cold.
You have a plug in the correct heat range? You have the plug gap past spec or under spec? If cold telemetry starts well enough needing that rich map in the morning is the ECU has captured the water temp, the TPS and all is ready to fire.

Air cleaner or plug change is might be something as setting a higher idle adjust and you are done pulling off parts that work fine in the morning start.

 

[Paul Higg]

Thanks Jake, but since this thread has been going for a while, could you be a little more specific? Which intake are you talking about? The IAC or the EGR?

Paul

 

[Paul Higg]

If it starts right up cold in the morning, where is the air leak? Where is the clogged part that is causing a hard start? Would not a clogged air cleaner run the engine rich in the warm start? That would mean fuel is getting to the cylinder? You had to push on the pedal to start on a hot day? Does that mean more air because you have to match the over rich condition?

How much over-rich is that on cold start-up where it works and starts fine. You might be chasing your tail is more the TPS on the throttle app. I doubt it since it starts so well cold.
You have a plug in the correct heat range? You have the plug gap past spec or under spec? If cold telemetry starts well enough needing that rich map in the morning is the ECU has captured the water temp, the TPS and all is ready to fire.

Air cleaner or plug change is might be something as setting a higher idle adjust and you are done pulling off parts that work fine in the morning start.

I do not know if the plugs are in the correct heat range because I have never had them out. I just bought the car in January so I do not know what maintenance was done on it. One thing I have noticed is that if I turn the key to run and let the fuel pump run for three seconds it will start right up. So I think it may be fuel pressure related. And from what I have read changing the plugs can be a real nightmare so I am going to have my mechanic do it soon. He's been overhauling just Vettes for 32 years. He does good work and I trust him.

 

[Toms007]

Dang Paul, I wish I lived closer, I could help you do that plug change. I am guessing that you are correct in thinking it might a be a fuel pressure issue.

 

[Paul Higg]

Now that is REALLY nice of you Tom, I appreciate it a lot.