...
I test drove it and it went great. I am trying not to get my hopes up, but I am optimistic about how it is driving right now. I'm gonna give it a little more time before I cross off the clunk noise and the shake as "fixed", but again I'm happy.
Since doing that whole procedure (disconnect IAC --> set minimum air --> adjust TPS), the Blazer has been driving really well. The only thing that was bugging me was that I felt like the idle was pretty high. I decided that I was going to repeat the whole thing because I wanted to do a couple of things differently:
- I wanted to let the engine warm up to operating temp. The last time I did it, the engine was cold.
- I wanted to be really crisp about checking/verifying my engine's RPM as I went. The last time I did it, I just went off of my ear.
When Googling about how to best measure my engine RPM, I found this
photo tachometer from HF. I decided to go for it after watching a review video on YouTube. It comes with some reflective tape, but in the video they mention that you can just use aluminum foil tape so I bought a roll of that also.
I slapped a strip of tape on the inside of my crank pulley and gave it a shot. It seems to work fairly well. Here is a video of me using it. It takes about 25 seconds before I get the camera to show everything (sorry about that).
View attachment IMG_0147.MOV
In the video you see that the crank is spinning at 570 RPM, but when I first got under there it was at 740 or something like that. Definitely way too high. After shooting the video I got it down to about 535 RPM before proceeding onward.
I think that I may have mentioned this in my prior post... but when checking the TPS, the old Eagle Mark threads say that you should shoot for 0.54V-0.6V to start. When checking this time it was at 0.54V on the dot. I was so happy to see that... rocking the TPS back-and-forth is kind of a pain. I left it exactly where it was at.
The only thing still bothering me is that those same Eagle Mark threads say that when at WOT, your TPS should be showing something like 4.5V-4.8V. Mine was showing something like 4.2V at WOT. I don't know how that will translate into the driving experience. When flooring the gas pedal I want it to GO lol.
I have yet to test drive it, but I'm optimistic. I'll report back as soon as I get the chance to shake it down.
EDIT: I should mention that doing all of this really made some mental lightbulbs go off about how the TBI system works end-to-end. I am really starting to finally feel comfortable with TBI. I think that I could buy a non-running TBI truck and get it going again with what I have learned. It makes me feel really happy and I just couldn't help but share.