Question for you boys(gals), I pulled the header off the other day and the #4 primary looking down the header tubes looked white while the others looked like they're supposed to with a black carbon look. Now, could this be a situation of a tune not enough fuel or the injector going bad? I have the '730 ecm if this matters but what could it be if its not a lean situation? Thanks for answering the questions!!!

 

Since the injectors are batch-fired with that ECM, the problem would be more likely with an injector instead of the ECM. There may also be a vacuum leak in that runner (intake, injector 'O' ring, plenum flange or tube) that is affecting the mixture.

It's also possible that the exhaust valve is not sealing in #4, creating a hotter condition at that exhaust tube.

If compression or cylinder leakage testing doesn't reveal a mechanical problem and no vacuum leaks can be found, I'd suspect an injector flow that is different. Unless you have the means to statically and dynamically flow test the injectors, you may want to seek professional help. There are several potential causes for an injector to reduce output flow. A good injector shop will test them all.

Before sending them off for service, you can perform your own, somewhat crude test of injector performance on the vehicle. That may indicate a grossly under-performing injector.

If you are certain the ignition system is functioning, you have no vacuum leaks, there is adequate fuel pressure, and you have good compression on all holes, you can to perform a power balance test to locate the offending cylinder(s). I had a similar problem with my TPI and the test isolated the dead holes.

To perform a power-balance test, connect a diagnostic tachometer, start the engine, allow it to reach operating temperature, then bypass the EST system and unplug the IAC electrical connector while the engine is idling. Unplug the electrical connector from one injector and monitor the engine RPM as it is disconnected. The drop in idle RPM should be relatively equal for each cylinder. Replace the electrical connector and go on to the next injector. You need to realize that the ECM will sense the RPM drop and attempt to compensate by adjusting the IAC, which is why it was disconnected in the first place. Changes in actual engine RPM may also affect the ECM’s target for timing advance, so that should have been bypassed as well.

Compare the RPM drop at each cylinder. Don't forget to replace the IAC connector. If one or more injectors caused little or no change in RPM, it is not flowing fuel at the correct rate or if it has a poor spray pattern.

NOTE: This test will not be accurate if the ignition system is not in good order or compression is low on a cylinder.

This test allowed me to identify two defective injectors, and test results after removal of the injectors confirmed that - two of them had very poor spray patterns and low flow rates. The engine had 18,000 miles and I had already tried several types of injector cleaner in the fuel tank and a “professional” on-car cleaning at the dealer with the pressurized fuel rail system (MotorVac), all with no improvement.

Again, if you discover a bad injector(s), I would recommend contacting Cruzin' Performance.

 

Burning water can make an exh tube turn lighter in color.
Are ya mysteriously loosing coolant??

 

yea, a little.....but i've had some leaking hoses so I can't tell you for sure.

 

but if I do have a coolant leak, where would it be coming from and would if damage anything to stay like it is.

 

My 4 bolts on the intake in the middle were loose on both sides so I tighted them back down, so I reckon we will see if that helps. I also had some lose water hoses but my coolant level seems to be steady right now.

 

The intake manifold-to-cyl head gasket would be a likely place for coolant to enter the cyl. I don't know of any adverse effects that a small amount of coolant being injested by the eng would cause. If the leak was on an odd numbered cyl, the O2 sensor might be effected.

 

Well, it was on the even number side and the odd side looked fine when I was replacing the gasket so, I will keep ya'll informed of how its going.

 

I kinda made up a procedure to check injector flow. Made myself a test harness from an old wiring harness. It has 4 inj connectors wired together and a place to apply power and ground. Raised inj rail high enough to get some containers (cut-up oil bottles in my case) under the injs. Jumped fuel pump to run. Then tapped power wire on the batt post so the injs got very short duration power pulses. Did abt 100-150 taps then measued the amount of fuel in each container using a graduated cyl. Had abt 100 CC in each container. They all came out within 1 cc of each other. Kinda getto but it did give me a warm fuzzy feeling afterwards.