Help understadning my CJ7 SBC datalog

[Dlxman]

Hi Tato, thank you for your input. All the basics have been checked as good or new. Cap and rotor were replaced last year with a bad connection to the ignition module under the GM HEI cap. I have completed vacuum leak tests on all areas including the throttle shaft to end up clean! Which is good. As Steveo had mentioned, originally the injector spray pattern was good after the "cleaning and gasketing" of the TBI.
I checked it this evening, and behold the right (passenger side) put out no fuel. This was after warm up and closed loop. The left side had a cone, but seemed a little wet, not a fine(ish) mist. I did swap the RH to LH connectors to see if it was in the wireing, but no difference. Not sure if this was the right way or not. Regardless, I am going to pull the injectors and either clean or replace them.

I will let you know by this time next week if it was successful, as it will take time to get it done, and be back in town to try it out.

How do I know which injectors I have? No markings....??? TBI #17089018 3459 JWZ

[tayto]

that # appears to be the number stamped on the TBI unit itself. if the injectors have no number etched in the top or paint markings the only way to determine what they are is to get them flow tested @ 13 or 14 psi

http://www.gearhead-efi.com/Fuel-Inj...d-part-numbers

[dave w]

Perhaps a picture of the EXTREMELY UNUSUAL Knock (sawtooth pattern) will be helpful?

dave w

Knock.jpg

[dave w]

Perhaps a picture of the EXTREMELY UNUSUAL Knock Accumulation will be helpful?

dave w

Knock.AccumulatorJPG.JPG

[tayto]

i would focus on the injector that's not firing personally. 4 cylinders not firing might be what knock sensor is detecting.

[Dlxman]

Hello All, I have had the injectors ultrasonically cleaned and replaced. Still runs poorly after warm-up. The data log from 8/26 is attached. I also have no idea why the sawtooth pattern exists. Could this be a bad ground?
Checking the spray pattern with a timing light (cyl 1), I could only see the one injector spraying (again), but do both injectors fire simultaneously, or do they alternate? I could see fuel hitting the port of the throttlebody on the injector that appears not to be firing.
I have two new matched injectors on the way, but wont ship until after Sept 1.

Thank you once again for your support and suggestions. I'm not one to give up or afraid of hard work!!

[dave w]

I have only looked at the first data log posted in this thread. It seems odd to me the engine would be running rich with only one injector working.

Perhaps a quick timing light test of unplugging one injector at a time would be a worthwhile experiment?
Ignition key off ... unplug one injector ... start the engine and check spray pattern with timing light ... repeat test on other injector.

Seems one of the logical outcomes of the above test might be . . . if one injector is not working ... the engine won't start?

Sawtooth knock pattern, possibly measure the resistance of the knock sensor. Remove the electrical connector from the knock sensor and measure from where the were the electrical connector was plugged into (center of knock sensor) to ground.

dave w