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Discussion Starter #1
So, as some may already know I just got done with dealing with the crank sprocket and reluctor gear fiasco.

Car runs and drives now, awesome!

As for my issue, I installed an adjustable exhaust cam gear which many are familiar with. I set mine to approx -3º, maybe a little more but certainly less than -4º.

Does the ecu not know what's going on? I'm getting some misfires under heavier loads.

Now I also was playing around with old coil packs to diagnose the broken sprocket, so there is a chance that is the issue. But in the event that it isn't, I guess I have to go back to the old exhaust gear

I do plan on changing the coils back to my newer ones, but would like to get some input on the issue, thanks
 

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So, as some may already know I just got done with dealing with the crank sprocket and reluctor gear fiasco.

Car runs and drives now, awesome!

As for my issue, I installed an adjustable exhaust cam gear which many are familiar with. I set mine to approx -3º, maybe a little more but certainly less than -4º.

Does the ecu not know No the ECU does not know. If you are running cats. 4 degrees retard is fine. If you are not running cats. You can run up to 6 degrees.
 

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Discussion Starter #3
I seem to have fixed the problem, I cleaned my MAF sensor since it was throwing a code, and replaced the coils back to the newer ones, and no weird misfires or stuttering since.

Does the ecu not know No the ECU does not know. If you are running cats. 4 degrees retard is fine. If you are not running cats. You can run up to 6 degrees.
As for the cat/no cat situation, I have never read this until now. 6º seems pretty aggressive. Does anything past 4º even yield any more power?
 

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Pretty sure most of it is "seat of the pants" power, nothing substantiated. But i could be wrong, i would imagine it is just moving the power band around a little more than anything else.

Did you reset the ECU when you changed the coils back and forth? The resistance is going to be different so that wont help, the ECU will need to relearn the resistance before it can run properly. I changed the plugs in mine a few years ago now, reset the ECU and it still ran like a bastard for the first few minutes, rough and coughing. Then just settled down like nothing had happened and ran sweet ever since. Same type and brand of plug (OEM denso iridium), but I guess the ECU had a bunch of new resistance to calculate out, along with the "new plug smell" it had to burn off. :D Not saying yours is the same, but the ECU does have to relearn stuff so a clean reset is always a good idea.
 

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I seem to have fixed the problem, I cleaned my MAF sensor since it was throwing a code, and replaced the coils back to the newer ones, and no weird misfires or stuttering since.



As for the cat/no cat situation, I have never read this until now. 6º seems pretty aggressive. Does anything past 4º even yield any more power?
Yes, to more power range. But gets the exhaust hotter. Witch is bad for cats and will cause codes to pop up. Unless you take the cats out and bypass or fool the downstream o2 sensors.

4 degrees is safe for stock configuration. More need other changes to work right.
 

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Discussion Starter #6
Pretty sure most of it is "seat of the pants" power, nothing substantiated. But i could be wrong, i would imagine it is just moving the power band around a little more than anything else.
Ya, 6-8 HP up top isnt much, but you figure I've done plenty other to give me small gains. I.e.: lighter wheels, pulleys, driveshaft, etc

So it all adds up over time, and I can say it certainly does well despite it being only an N/A motor

Did you reset the ECU when you changed the coils back and forth? The resistance is going to be different so that wont help, the ECU will need to relearn the resistance before it can run properly. I changed the plugs in mine a few years ago now, reset the ECU and it still ran like a bastard for the first few minutes, rough and coughing. Then just settled down like nothing had happened and ran sweet ever since. Same type and brand of plug (OEM denso iridium), but I guess the ECU had a bunch of new resistance to calculate out, along with the "new plug smell" it had to burn off. :D Not saying yours is the same, but the ECU does have to relearn stuff so a clean reset is always a good idea.
Hm, sounds about right. Like I replied to Solar, I seem to have fixed it since I got a code for my MAF sensor and went back to the newer coils. Revved it all the way out to 6500 and seems perfectly happy.

Yes, to more power range. But gets the exhaust hotter. Witch is bad for cats and will cause codes to pop up. Unless you take the cats out and bypass or fool the downstream o2 sensors.
I changed the stock headers, so that leaves me with 2/3 of the cats, not sure if it would make that much of a difference for the last one. I'm already just living with a P0125 and P0135 😒

4 degrees is safe for stock configuration. More need other changes to work right.
Well I went with ~3º just to see what would happen, unfortunate part is I reinforced the gear with better hardware. And in order to make any changed I need to remove the entire gear. So I'll probably leave it alone for a while. Kinda tired of tearing it apart after 5-6 times
 

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Discussion Starter #8
...so that leaves me with 2/3 of the cats...
I said I was left with 2 out of 3 total, but I meant to say I removed 2 out of the 3. Meaning I only have a single cat remaining.


Need no cats for max timing change.
But like you say here, I guess all 3 cats must be removed. Which from what I've read, at least one cat needs to stay due to a required back pressure for proper engine operation.


As for the codes. Bank 1 sensor 1 O2 needs to be replaced. The other is a bad thermostat.
I'm just waiting until I go full standalone before dealing with the O2 sensors. I've tried making the O2 sim myself, but was running into some issues, let alone trying to manage a proper install.

I wouldn't be surprised if it was a bad thermostat, however when I looked up the code, it states that a bad thermostat could be one of many problems. One of which could also be another O2 sensor since it's a heater code.

I still have the issue when it gets cold outside the dash coolant gauge reads being like 130° instead of 170° like it should. I just haven't gotten around to doing the replacement. Was going to do so when I change the water pump and flush the coolant system.
 

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On all of mine that are N/A right now. Aftermarket header and down-pipe. With o2 simulators on secondaries. The down-pipe is a Megan. I have been too lazy to make a larger diameter one. It is the only bottle neck in the cars exhaust I have. Other than the rest of the exhaust system on some.
 

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Discussion Starter #12
On all of mine that are N/A right now. Aftermarket header and down-pipe. With o2 simulators on secondaries. The down-pipe is a Megan. I have been too lazy to make a larger diameter one. It is the only bottle neck in the cars exhaust I have. Other than the rest of the exhaust system on some.
So the downpipe you're referring to is the y-pipe/final cat, right?

Do you not lose any torque down low from a loss in back pressure? That's kinda how I always thought of it. When I had an exhaust leak at the merge point of the headers and y-pipe, I had a huge loss in torque and big gains up top with power

How did you do your O2 Sim? I tried making the one that you can find online, but was unable to get an oscillating signal. But even if I got the correct output signal, installation is the other portion I was somewhat unclear on.

On all of mine that are N/A right now.
How many do you own?
 

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So the downpipe you're referring to is the y-pipe/final cat, right? Yes

Do you not lose any torque down low from a loss in back pressure? That's kinda how I always thought of it. When I had an exhaust leak at the merge point of the headers and y-pipe, I had a huge loss in torque and big gains up top with power
On average about 8 ftlbs
How did you do your O2 Sim? I tried making the one that you can find online, but was unable to get an oscillating signal. But even if I got the correct output signal, installation is the other portion I was somewhat unclear on.
I was going to start making some eventually to sell. But if you want one. Karl Long sell them. His work fine.


How many do you own? Down to 3. But I help a lot of people local also.
 
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