Coke Car running lean...
#76
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Sits in the merge collector, and yes, I did a free-air. So technically it's only measuring one head, but I've done that on my other (SCed) cars without any significant variability from one side to the other. I know ideally I should place it after the Y but I don't have an available bung there.
#77
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So it sounds like you're good, there.
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I'm seriously suspecting the MAF.
I'm surprise others with the S300 chips (and a US-rebuilt MAF) have not had issues.
I'm going to try my other spare MAFs and see if there is any change. Will report result later today.
I'm surprise others with the S300 chips (and a US-rebuilt MAF) have not had issues.
I'm going to try my other spare MAFs and see if there is any change. Will report result later today.
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"Generic" chips have always had limitations, simply because no two engines are exactly the same....especially 30 year old engines with 30 year old components! The 3.2 liter 911 Carreras, which also had Bosch injection (from a similar time period), had an adjustable potentiometer inside the brain to that allowed "fine tuning" of the engine.
Once you have the correct fuel pressure, the correct injectors, and a couple functional temperature senders, WOT mixture on the 1985-1995 vehicles, is almost completely dependent on the MAF and the computer (chip set).
You are on the correct path. A different MAF will tell you if you have a "chip issue".
#80
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The stock chip is 'generic' and it works pretty well. If y'all can't get a car to fuel properly or there is a sensor or wiring issue that prevents returning the car to near stock condition, then don't blame the 'chip'. ![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
The WOTpot was for folks that may have added a larger exhaust system (not just a X-pipe) or injectors that were much different than stock. Andrew is using the stock injectors and it is still lean with the stock LH chip with the higher pressure S4 FPR so there is obviously still a problem somewhere.
What is the idle AFR with B->C connected?
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The WOTpot was for folks that may have added a larger exhaust system (not just a X-pipe) or injectors that were much different than stock. Andrew is using the stock injectors and it is still lean with the stock LH chip with the higher pressure S4 FPR so there is obviously still a problem somewhere.
What is the idle AFR with B->C connected?
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yes, from your video .. WAY too lean.. and i mean, 14.7 is very dangerous.. surprised you didnt have a ton of pinging.
figure that one out and you will have a bunch more power too.
figure that one out and you will have a bunch more power too.
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The stock chip is 'generic' and it works pretty well. If y'all can't get a car to fuel properly or there is a sensor or wiring issue that prevents returning the car to near stock condition, then don't blame the 'chip'. ![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
The WOTpot was for folks that may have added a larger exhaust system (not just a X-pipe) or injectors that were much different than stock. Andrew is using the stock injectors and it is still lean with the stock LH chip with the higher pressure S4 FPR so there is obviously still a problem somewhere.
What is the idle AFR with B->C connected?
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
The WOTpot was for folks that may have added a larger exhaust system (not just a X-pipe) or injectors that were much different than stock. Andrew is using the stock injectors and it is still lean with the stock LH chip with the higher pressure S4 FPR so there is obviously still a problem somewhere.
What is the idle AFR with B->C connected?
Do you think unplugging the O2 sensor would shed any light?
I'm going to try one other MAF, and if that doesn't solve it, I'll shark tune the bitch to get it safe and then go have some fun. I'm missing a track day tomorrow!
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Agreed. There is power there for sure. It's already better, but WAY too dangerous.
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LH 2.2 doesn't learn, so the O2 sensor shouldn't affect WOT. How do the plugs look? Do you have any that are too clean? IE. bad injector or spark plug misfire? One jug not firing will dump a lot of air into the exhaust.
If it does come to down to using the SharkTuner, you can still use the S3.S300s EZF chip as long as you keep the AFR below 13 at WOT. (The brains don't communicate.) If using the S4 FPR, start with something like a 27# injector in the ST.
If it does come to down to using the SharkTuner, you can still use the S3.S300s EZF chip as long as you keep the AFR below 13 at WOT. (The brains don't communicate.) If using the S4 FPR, start with something like a 27# injector in the ST.
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LH 2.2 doesn't learn, so the O2 sensor shouldn't affect WOT. How do the plugs look? Do you have any that are too clean? IE. bad injector or spark plug misfire? One jug not firing will dump a lot of air into the exhaust.
If it does come to down to using the SharkTuner, you can still use the S3.S300s EZF chip as long as you keep the AFR below 13 at WOT. (The brains don't communicate.) If using the S4 FPR, start with something like a 27# injector in the ST.
If it does come to down to using the SharkTuner, you can still use the S3.S300s EZF chip as long as you keep the AFR below 13 at WOT. (The brains don't communicate.) If using the S4 FPR, start with something like a 27# injector in the ST.
I might also try a different WBO2 just in case the one that I'm using is wonky.
I really appreciate all the support. Especially from the robots.
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#85
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OOooo... Ooo. Mr. Kotter! Mr. Kotter! ![jumper](https://rennlist.com/forums/graemlins/jumper.gif)
How about a weakish fuel pump? I could hook up the Go Pro and see if the Fuel Pressure falls (or fails to rise) on a full-pull. That would explain things, wouldn't it? I have no idea how old the fuel pump is, so it's worth a try and I happen to have a brand new fuel pump should it happen to be weak.
Thoughts before I chase my tail?
![jumper](https://rennlist.com/forums/graemlins/jumper.gif)
How about a weakish fuel pump? I could hook up the Go Pro and see if the Fuel Pressure falls (or fails to rise) on a full-pull. That would explain things, wouldn't it? I have no idea how old the fuel pump is, so it's worth a try and I happen to have a brand new fuel pump should it happen to be weak.
Thoughts before I chase my tail?
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Originally Posted by AO
OOooo... Ooo. Mr. Kotter! Mr. Kotter! ![jumper](https://rennlist.com/forums/graemlins/jumper.gif)
How about a weakish fuel pump? I could hook up the Go Pro and see if the Fuel Pressure falls (or fails to rise) on a full-pull. That would explain things, wouldn't it? I have no idea how old the fuel pump is, so it's worth a try and I happen to have a brand new fuel pump should it happen to be weak.
Thoughts before I chase my tail?
![jumper](https://rennlist.com/forums/graemlins/jumper.gif)
How about a weakish fuel pump? I could hook up the Go Pro and see if the Fuel Pressure falls (or fails to rise) on a full-pull. That would explain things, wouldn't it? I have no idea how old the fuel pump is, so it's worth a try and I happen to have a brand new fuel pump should it happen to be weak.
Thoughts before I chase my tail?
You could log fp, timing, fuel pulse, etc..
Aim pista, Motec etc....?
Just my $0.02
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It is appearing that you might want to invest in a data logger. That way, you can monitor all aspects of the engine and check the logging files and data before and after something odd happens.
You could log fp, timing, fuel pulse, etc..
Aim pista, Motec etc....?
Just my $0.02
You could log fp, timing, fuel pulse, etc..
Aim pista, Motec etc....?
Just my $0.02
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very easy to do..... just jack up the back of the car, mount the fuel pressure guage on the fuel rail, and then have someone watch the gauge as you use 4th gear at 3000rpm and then floor it slowly while also appling the brakes.... this way, you get no run away wheel spin, you get to see WOT,and you dont need to mount up a go pro and a light under the hood.
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On a whim, I measured the Temp II. Current ambient temp is ~80F and car is 100% cold.
On both sides I get ~1.9k Ohms. Seems a bit low doesn't it? I think it should be more like 3k. I'm going to dig around to see if I can find the one on my GT (it's in pieces) and measure that for reference.
Yeah! Way easier! I'll give that a try first.
On both sides I get ~1.9k Ohms. Seems a bit low doesn't it? I think it should be more like 3k. I'm going to dig around to see if I can find the one on my GT (it's in pieces) and measure that for reference.
very easy to do..... just jack up the back of the car, mount the fuel pressure guage on the fuel rail, and then have someone watch the gauge as you use 4th gear at 3000rpm and then floor it slowly while also appling the brakes.... this way, you get no run away wheel spin, you get to see WOT,and you dont need to mount up a go pro and a light under the hood. ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
#90
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Temp II problems are usually over-enrichment when hot or lean when cold.
S4-up there is error correction for out-of-range temps - the LH switches to a warm default.
S4-up there is error correction for out-of-range temps - the LH switches to a warm default.