4.3 CPI Injector replacement pictures

[blackmarocraig]

Ok heres whats happening now, I just went out for lunch and started it and it started rough then smoothed out then as I sat at McDs it started to idle rougher and rougher so I floored it in nuetral and it smoothed out. Then as I sat there longer it started to get hot like above half way on the guage. So I started back to work and it cooled back down. Im sooo lost

[BlazerLT]

How about you start looking into your cooling system to see if it is topped up instead of driving around with it running this way.

[BlazerLT]

Originally Posted by blackmarocraig

well what else could it be where I am just losing coolant after new radiator, hoses, gaskets? It starts rough as if it was compressing liquid in the chamber instead of gases. I am going to check a plug or two tonight but I dont have money to keep taking it to shops to diagnos ya know. This thing has already drained my account of flow.

It isn't that, your rad cap could be defective and not holdig pressure, but the CPI injector will not cause an engine to ovreheat.

[blackmarocraig]

Well I have checked it cold every morning since i finished the job and its low before I ever even run it if thats what you mean? I was told to do my Fuel Pressure Regulator so I called all over the place and no one seems to know what Im talking about. So where the heck can I order one from online cause I am having no luck at local shops!!!

[BlazerLT]

Originally Posted by blackmarocraig

Well I have checked it cold every morning since i finished the job and its low before I ever even run it if thats what you mean? I was told to do my Fuel Pressure Regulator so I called all over the place and no one seems to know what Im talking about. So where the heck can I order one from online cause I am having no luck at local shops!!!

Ok, relax a bit, you are coming across quite frantic.

1.) What coolant are you topping the rad up with in the morning? Are you topping it off when it is low? Are you topping up the rad or the overflow tank?

2.) Replace the rad cap with something that is not AC delco, get the appropriate Stant Branded cap from your local Autozone.

3.) The new CPI injector has the new regulator on it. It is brand new. Don't listen to your friend anymore, he doesn't know what is going on and is only confusing you.

You just had your rad replaced? How long ago?

[blackmarocraig]

ok this last week I replaced the CPI, radiator, hoses, gaskets and cleaned the EGR. I have a Prestone radiator cap and I use the orange dex-cool. Could it still be the ween hole and seal in the water pump?

[BlazerLT]

Originally Posted by blackmarocraig

ok this last week I replaced the CPI, radiator, hoses, gaskets and cleaned the EGR. I have a Prestone radiator cap and I use the orange dex-cool. Could it still be the ween hole and seal in the water pump?

No, you would smell it if you had a leak.

Are you mixing the dexcool and water 50/50?

also, remember when you replace cooling components you are going to have to purge the air out of your cooling system.

T do this drive your engine up on ramps and while cold remove the rad cap and get inside your truck and turn the temp dial all the way to hot and set the controls to heat.

Fill your rad to the top and then startup your engine, have the engine set to run at about 2000rpms and allow the engine to come up to temperature.

Watch as the thermostat opens and the coolant in the rad drops considerably. Keep on topping up the coolant until it doesn't drop anymore. It might burp a couple of time and the rad level will drop as the air is burped into the rad which will allow coolant to replace it.

when after 10 minutes the level does not drop, attach the rad cap on again and return your engine back to idle.

Fill the overflow tank to 1/2 inch below the overflow line connection you will see when you look into the overflow tank.

Also, did they flush your overflow bottle out?

Did you change your oil after the CPI replacement?

[blackmarocraig]

Well Im mixin 50/50 but the purgeing I have not done. I dont have access to ramps though so I will have to figure something out. I also did not flush out my overfill tank. I did however change my oil after I finished the CPI. I appreciate all your help so far.

[BlazerLT]

Get one of those syphon hoses with the pump on the end and pump out the overfill resevoir and flush it and pump it out about 5 times to get rid of all the grime and crud that could be blovking the coolant passage that keeps the rad topped up when the level drops.

[93LT]

Originally Posted by blackmarocraig

OH GOD! I changed gaskets, CPI, Fuel lines(NUT KIT), hoses and cleaned EGR and port and when I run it then shut it off go back and start it after like an hour it starts real rough and chugs for about 2-5 secs then is fine. Now it did this a week ago and overheated and that was the whole reason I replaced all those parts cause Meineke told me thats what was wrong. Do I have a blown or small hole in my head gasket now? Im freakin out here

If you had a head gasket leak, you should see water being steamed out of your exhaust pipe, more so than just engine warm up steam on a cold day. Also, you would notice the antifreeze level going down in the radiator/overflow tank, along with an antifreeze smell out the exhaust.

A plugged converter can cause over heating. Not saying that is your problem, just pointing that possibility out.

One other possibility with a jerky idle would be vacuum leaks, mainly the vacuum line off the back of the plenum, which goes to a "Y", then to a 4 way valve. From this valve it run to the main canister, transmission, cruise control and your ventilation controls (or at least it does on '94 and prior models). This same vacuum leak can cause your tranny to have spastic fits with the lock up tork converter, generally most noticeable when you first reach your top speed and level out under normal acceleration.

Another possibility for poor idling performance is bad plug wires. Yes, plug wires can give a poor idle yet run fine under acceleration.

[93LT]

Originally Posted by blackmarocraig

ok this last week I replaced the CPI, radiator, hoses, gaskets and cleaned the EGR. I have a Prestone radiator cap and I use the orange dex-cool. Could it still be the ween hole and seal in the water pump?

What about a new thermostat?

[blackmarocraig]

I am not having a overheating problem like I thought sorry my thermo must have been stuck cause it worked fine later but still have the rough startup til I rev it. I will try to purge my system and clean the overflow tank and add coolant if needed. All these ideas are starting to get off on different tangents and I can only do so much more. I also do see alot of steam at start up even when it was 52 this afternoon so I will smell the exhaust and watch the levels tomorrow and see what happens.

[93LT]

The photos in this seem to help people comprehend the task at hand, how out a sticky?

[Cailen]

As you can see by this first photo I was not as fortunate, and did not catch it early. The whole left side is fuel washed because of my leaky fuel pressure regulator. It also looks like injectors 1 and 3 are starting to leak a little too. Though this photo shows that my nut kit is not leaking (yet) I chose to replace it anyway.



My EGR was about 30% clogged and I'm fairly certain I'll need to be replacing my cat soon. It was so bad I decided to take off the complete manifold and clean up what I could. Below is a picture of the lifter valleys, as well as a picture of an exhaust port that was almost entirely clogged with rock hard carbon.





And of course, just for good measure:

[93LT]

I always wondered what the balance shaft looked like in the 4.3 engine. That was first added in 1992, and only the vortec engine received it initially. I believe by 1993, all 4.3 engine received the balance shaft.

I had a 1992 Full Size Chevy Short Bed Sport (new) with the TBI version, it was one rough idling engine.