1996 Collector Edition Corvette

[wxo]

Another successful day today. I set up my home-made injector cleaner/tester and I'm pleased with the outcome.

I partially fill the cylinder with injector cleaner and then pressurize it to about 48psi. Then I turn on the main petcock and listen for any leaks. Then I hit the button to energize the injector solenoid and watch the pattern through the transparent jar. The first injector I looked at was from #6 cylinder which displayed a sooted spark plug that was different from the rest after the flooding incident. The spray pattern was not uniform so I held the button to clean it out until the pattern returned to normal. Then I tested a brand new injector to see what the pattern should look like. Finally, I tested the one from #8 cylinder. It, too, had a non-uniform pattern and, again, I was able to run the cleaner through it until the spray pattern returned to one that looked like the new one. From here I plan to test and clean all eight injectors to get the fuel system ready for installation when the time comes.

[MostMint]

Nice. I have to believe that what is affecting those injectors was stuff left in the lines from sitting all that time before you got the car

[wxo]

Seems to me the fuel filter should have picked up any debris left in the lines after I flushed them out. However, when I pulled the fuel rail apart after the flooding incident, I found a little debris left behind after my first cleaning. I did another thorough cleaning of the rail hoping it's clean enough this time.

[TireSmoker]

Thats slick, Walt! I love how its basically self-contained with 9v battery.

-Dave

[wxo]

I used this guy's idea: https://youtu.be/twXhiVLb9H4

[MostMint]

Seems to me the fuel filter should have picked up any debris left in the lines after I flushed them out. However, when I pulled the fuel rail apart after the flooding incident, I found a little debris left behind after my first cleaning. I did another thorough cleaning of the rail hoping it's clean enough this time.

well the filter can only pick up stuff upstream from its location. did you replace the flexible hose on the pressure side? It's possible that 25 year old hose is starting to come apart. If you can locate any of the bits that came out in the cleaning you might get a clue as to what they were.

[wxo]

Yes. Those hoses escaped my attention altogether.

UPDATE: Actually, upon reflection, I had tested these lines previously by pumping about a pint of gas through the supply line into a glass bottle. The gas came out totally clean so I pronounced the supply line good.

UPDATE 2: I inspected the inside of the braided supply line today. With a dental scalar, I reached inside to test the flexibility of the inside lining. I was hoping to feel the flexibility of the rubber and maybe scrape off a sample to inspect. I was surprised because the inside hose appears to be a flexible plastic material rather than rubber like a brake hose. It would be interesting to verify this from some authoritative source.

[wxo]

I satisfied myself (with my light and dental pick) that the inside of these braided fuel lines on my '96 LT4 are not rubber and that they likely won't be flaking off rubber into my fuel system. So after two months of down time, I put everything together and got it started again. Once started, it threw a P00100 and a P00122 (TPS sensor and MAP sensor codes). I removed each of the connectors, sprayed contact cleaner on both parts and snapped them back together again. No more codes. The LT4 starts and runs smoothly. Now I need to get some gas and take it out on the road for some additional testing. The temperature is supposed to be 71° today in Raleigh so it should be nice top-down weather.

[wxo]

My test driving this afternoon was fun and there were no surprises. The first thing I noticed was the instant starting. Secondly, running with the OEM fuel pressure regulator, she ran quite well overall at stock fuel pressure. The bogging didn't show itself in normal slow driving but when pushing it bit more, i.e. when shifting from first to second at medium throttle and then accelerating, it coughed. I'm going to install the fuel pressure gauge and see what the pressures look like. I'm inclined to install the adjustable Aeromotive fuel pressure regulator and bump the fuel pressure up enough to get rid of the bog like I did before.

[wxo]

Another test run this afternoon showed that the LT4 still won't take medium to heavy acceleration without some feathering of the foot feed. The bog showed it's ugly head again so I installed the new adjustable fuel pressure regulator and will try again tomorrow. It is set to stock specs of 42 psi with the vacuum line connected.
Also, toward the end of my outing, an Engine Check light turned on. It was a P0410...Secondary Air System. But wait. I don't have Secondary Air anymore! Apparently the PCM knows it's gone. It's checks for extra oxygen in the exhaust under certain circumstances. I just turned off the light for now. With the extra working room around the engine, I will gladly turn off the light from time to time.
Another thing that happened is that the driver's digital display went blank. No speedo, gas gauge and other gauge info disappeared. I will tackle that when I get this engine running better.
Finally, today, I received the long delayed Delrin plastic rod from eBay. It will be used to rebuild my headlight motors. I should be able to get that done and install and test them tomorrow.

[wxo]

After increasing the fuel pressure from stock 42 psi to 48 psi, there was a noticeable difference in response to the foot feed. It feels much better now. Note that it was set at 58 psi to get this same level of response before. Another big check mark off my list is the headlight motors. They both work normally again when the headlights are turned on.

The intermittent digital display has become an annoyance now. I really need a speedometer and gas gauge but I'm not ready to pull the dash apart quite yet. I plan to use my UltraGauge as a backup speedo and gas gauge. The UltraGauge needs to be set up for the Vette so Maverick and I are going out for a run tomorrow afternoon to get that done. Each day I'm becoming more familiar with driving Silvia and the 6-speed makes it a load of fun.

[wxo]

Maverick and I took advantage of a beautiful 63° afternoon and put about 80 miles on Silvia. A lot of it was on open highway and we were running a little over 75mph much of the way. She ran beautifully, getting over 25mpg on the newly calibrated Ultra Gauge. This was a good confidence building trip. No surprises at all. ODO now shows 103,213, so I've put 213 miles on it since she arrived here on a rollback 6 1/2 months ago.

[wxo]

For every action...after Wednesday's 80 mile jaunt and perfect ending, I pulled out of the garage last night to go to choir practice and noticed something wonky. It felt like the left rear parking brake would not release. Turning around and back in the garage I looked and saw a flat LR tire. I haven't had a flat tire in decades. Thinking back, Maverick and I had pulled over to the shoulder two times to calibrate my UltraGauge. That's the most likely place I could think of where I could have picked up the nail. Thankfully the object is in the meat of the tread directly in the middle. I'm taking it to the shop for a proper repair this morning.

Also, yesterday being quite warm (73°) it turned my attention to Silvia's AC system. With nothing to lose, I just added a can of R134a to see what would happen. To my surprise, I got cold air out of the vents. Unfortunately, I noticed that both the low and high AC port valves were leaking badly. The good news is I should be able replace them, evacuate it and have cooling for this summer.

[wxo]

I just learned about this unpublicized feature called "Flood clear". https://youtu.be/TQgYU0EoZFc It would have been nice to know about this when I actually had this situation. Wait a minute! How am I going to try this? I don't have 3 feet!! (clutch, brake, foot feed)

[Basement Paul]

You only have to hold the clutch and gas on manual cars, not the brake too. So you're good. Cool bit of info.

-BP

I tried this yesterday and it works. Cool.