Head gaskets don't necessarily leak coolant, although many times they do. They can leak compression, oil and coolant. They can leak coolant externally, or internally into the oil or into the combustion chambers. Lifters can make noise, especially when coolant gets into the oil. Checking valve springs is done visually, and by measuring assembled valve stem height. Camshaft lift is measured with a dial indicator. A compression test, (wet & dry) is used for checking the piston rings ability to seal against the cylinder wall. A cylinder leakage test checks the valves ability to seal the combustion chamber.

 

so where does this put me at with the P0303? didn't find any vacuum leaks. But as soon as I started it up when replacing the spider, I noticed my brake pedal went to the floor after having to remove the booster hose from the intake....theres another problem that I have no idea why it happened. Im out of ideas

 

Are you sure #3 injector line is not kinked?

Are you sure the driver side injectors are in the correct ports in the lower intake manifold? The cylinder numbers are molded into the injector housing. This image shows the passenger side labeled front to rear 2, 4, 6:



Two of them cross each other on the driver side.

Was the P0171 in memory before you replaced the injector assembly?

Brake pedal going to the floor is a bit of a puzzle: if the booster loses vacuum, the pedal will be high and hard. In an attempt to locate vacuum leak(s), try pinching off vacuum lines while the engine is at idle. If a line is leaking, pinching it off will cause the idle to smooth out, and possibly slow down.

 

yup I took the plenum off again yesterday to make sure nothing was kinked or pinched. everything looks peachy under there. double checked cylinder numbers to intake manifold and they check out. the P0171 was in the memory for about a week before I replaced the spider. and the P0300 vanished and came back as a P0303.
that is what I thought as well, with the brake pedal all of a sudden losing its firmness. I didn't touch anything with the brake system, only removing the hose that connects to the brake booster. it feels as if the system might need to be bled, but I have no idea why and I think its odd that in 4 hours it would just be like that after working on replacing the spider. The brake warning light is on too.
that picture you showed me earlier in this thread shows the vacuum lines; try pinching those vacuum lines only, and by pinching them you mean just squeeze it shut and the idle will smooth out If there is a leak?

 

Squeeze them shut, if the idle changes, there's a leak. Might be hard to tell because the IAC will adjust the idle speed very rapidly, unless you disconnect it before squeezing the lines.

If the brake warning light is on, there's probably a hydraulic leak, popped brake line etc. They like to rust out under the driver seat area inside the frame rail. If it's a 4 door, the fuel tank does not have to be removed to replace the line. DON'T let the master cylinder run dry.

 

I will check that tomorrow.
as far as brakes go, is there any other reason besides a leaking line that the brakes would do that? just curious

 

The warning light comes on when either of the two hydraulic circuits, (front or rear) experiences a pressure drop. The brake pedal goes down, the centering valve shuts off the system that failed, and turns the light on to let you know there's a problem, (as if you didn't already know) Look closely at the brake line from front, (inside left front wheel well) to rear, you'll see the wet spot. Don't bother trying to patch it, replace the entire line.

 

I hope by pushing the brake pedal down all the way I didn't overextend the piston in the MC. the ABS light has always been on since I got the truck, read the codes that basically needed the module replaced. when it starts, the light will be off until I hit ~3-4mph and if im braking at the time, the pedal will vibrate for a quick millisecond and the pedal will go a little farther down. was never a problem because when I pumped it again it would be normal again. Today, I figured since when I brake it pulls to the right I would unfreeze the pass. right caliper and after noticing while stuck in the snow the rear wheel would still spin even with the brakes applied. The pads were frozen in the bracket, it took a few blows from the hammer to break them loose. Thinking this would help, it didn't. so this being said, is the brake bleeding procedure still normal? (pump brake, open bleeder valve, close valve, release brake) or is there some other procedure because of the ABS unit...

 

ABS bleeding is the same as non ABS brakes, as long as the master cylinder does not run dry. If it runs dry, you need a scan tool capable of initiating the "Automated Bleed" procedure, (the el cheapo $500 jobbies are not capable).

The ABS does a self check on each start up. If there are no failures, the ABS light remains off. When vehicle speed reaches ~3 MPH, the ABS checks the wheel speed sensors, the vehicle speed sensor, and activates the ABS pump for a few milliseconds, (if you listen real close, you can hear it). If there are no failures in the second part of the test, the ABS light remains off. If it detects a problem, the ABS light comes on immediately, and a DTC is stored in memory. Again, gotta have an ABS capable scan tool to access the DTC's.

If brakes pull or fade to one side, the problem is on the opposite side, (brakes don't get better when there's a problem). If it's pulling to the right, the problem is on the left side, (not doing its job).

 

that is very helpful information, gave me a better understanding of how that worked.
Today was a very successful day, I checked for leaks on the driver side brake system...nothing. so I figured I would check out the rear calipers and sure enough they were both leaking out of the calipers themselves. slapped on some new ones along with pads and rotors and I now have a nice firm braking system.
You know that cylinder 3 miss ive been chasing? low and behold, I decided to pull plug #3 and sure enough it was fouled to all hell. threw in a new one and BAM, purrs like a kitten. The new MFI upgrade makes a difference as well. Still waiting for my digital cluster above to show me an improvement from AVG ECON: 15.9mpg...haven't seen it go up yet in about the 20 miles ive driven it. It also shows the option for "Fuel Used: xx gallons" is there any way to reset all this stuff back to zero and start fresh? I don't see any reset buttons around it unless im blind.


CaptainHook you are the man, I appreciate all the tips and help you've given me. kudos to you, sir.