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HELP! Logging Knock, injector size, .9v 02 sensor

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tyhoppy

15+ Year Contributor
119
0
Mar 27, 2006
New Bethlehem, Pennsylvania
1991 Eclipse GS Turbo. 3" exhaust, 14B turbo, 450 injectors with computer from a manual tranny car. I think. I took the computer out of the manual car and put in the auto. It ran alright, I thought I was running lean, so I found out that the injectors are different and that if i changed the ecu I needed to change the injectors. I took the injectors out of the manual car and they turned out to be 390s and the injectors that were already in the auto were 450s. I figured that since the manual ran good maybe the computer that was in it was for the 390s so i put them in and it ran like crap, so I put the 450s back in. I found that the person whoever put the 450s in used the seals for the top of the injectors to the fuel rail for the bottom, and it seemed like it was sucking air which could have made it run lean, and I notice that my manifold doesn't glow red like it did before i put the correct seals on the injectors.

NOW FOR MY MAIN PROBLEM:
I just got datalogger, because the car wasn't running like it should. I am getting a knock sum of 43 when i floor it, and the 02 sensor voltage stays at .9 Isn't this voltage for the 02 sensor good, I don't think I should be knocking with this reading from the 02 sensor. Does this mean I am getting too much fuel, or not enough. I am planning on doing the fuel pump rewire this week. will this help? Any and all input is appreciated, thanks.
 
.9 is lean it should be in the .94-.98 area. However I don't think its fully responsible for all 43 counts of knock. But its a start. I would def do the rewire and there should be an improvement.
 
I am not relying on it for tuning, but I needed to see what would make it run badly. I don't have any tuning tools, just the datalogger. I added some oil so it was a little over full and I am only getting knock in the 30s, but still getting some. That was at .92v What do you recommend I use for tuning at full throttle? The 02 sensor seems the best option for me.
 
You'd have to buy a standalone wideband o2 system for a good tune, but it sounds to me like thats not something you're interested in quite yet. Besides you'd then need an SAFC to actually do the tuning. Once you do the fuel pump rewire it sould bring the o2 up to where it should be. Also can you log timing to see if the ecu us pulling it because of knock?
 
Did the rewire tonight and I'm still getting the knock... as well as timing pulled. It does it even at around 3000 rpm. Would a fpr do the trick? Should I just go ahead and order an afc II or something of the like so that I can correct this problem. what would be best for driveability without having to moniter everything during everyday driving. I plan on giving this car to my mom once i get my talon done and she won't know how to do anything other than get in and drive. Thanks.
 
Checked base timing, no goo leakage, and injector seals didn't fix it. And it has gotten worse. It will hardly move now. When it's in park and free revving it I get knock now. Also when i go to drive if I hit the gas lightly at only 2 - 2500 rpm i get knock like crazy. Car won't even drive. I am thinking about trying a new knock sensor tonight, and if that doesn't work it I'm gonna change the oil and put in a quart of rislone to try to quite down the lifters. I've heard louder ones on my talon without it pulling timing, so unless the knock sensor is overly sensitive and picking up the lifter noise i don't think it's the lifters. Everything in the head is brand new, including the head.
 
I am not relying on it for tuning, but I needed to see what would make it run badly. I don't have any tuning tools, just the datalogger. I added some oil so it was a little over full and I am only getting knock in the 30s, but still getting some. That was at .92v What do you recommend I use for tuning at full throttle? The 02 sensor seems the best option for me.

Either a digital o2 voltage meter, wideband or EGT. Some people think EGT is better than wideband, but they both seem pretty accurate to me.
 
We're getting off topic. I'm still getting this knock!
 
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