No, not yet. I need to search for a thread on how to do it and will get back to working on the car this afternoon.
ifyouaint1sturlast
Banned Scammer - I'm whitemike.
ifyouaint1sturlast
Banned Scammer - I'm whitemike.
Correct. It's a constant misss, consistent throughout the RPM range. No breakup up top anymore, just the constant miss. I still want to try that igniter ground mod and see what happens, but it seems as if it's time to start isolating cylinders to identify whether or not the miss is local.
ifyouaint1sturlast
Banned Scammer - I'm whitemike.
Chrisco;1825899 said:
If it's consistent even at low RPM I would more suspect other components. How old are your plugs, wires, etc? Have you checked your timing? If the CPS is off even slightly and your ignition timing is off, especially on a 7M, will cause a misfire.
So, here's a new checklist for you:
-Check codes (again)
-Check timing with a light and according to TSRM (jumper the correct terminals, verify RPM, etc)
-Check/verify TPS setting according to TSRM
-Check/verify fuel pressure according to TSRM
-Check/replace ignition wear components like plugs and wires
I would say to check VF and all of that, but I don't believe the problem would be tune/o2 related if it's in all RPM ranges. If the o2 sensor had any role then it wouldn't happen at certain times (someone correct me if I'm wrong) when the ECU switches between closed/open loop. Unless of course a bad sensor (o2? coolant temp?) was causing the ECU to stay in closed loop mode or something.. but that's a shot in the dark.
Hope that helps.
If your doing the ignitor ground mod it would be good to run an external ground on the coil packs also 
I did both of these and it greatly improved my idle and 2000 rpm miss.
I did both of these and it greatly improved my idle and 2000 rpm miss.
Well, as in most cases, it's always something simple. Turns out the miss was due to a loose injector connector. Unfortunately, it's now breaking up at/past 3500 RPM. No codes present. I went ahead and performed the igniter ground mod, but that didn't have any effect on the breaking up. Excellent writeup by Crisp and regards to Jetcock for his input on the igniter circuit.
http://www.supramania.com/forums/showthread.php?52217-IGNITER-GROUND...-crispics
Reset fuel pressure again, this time correctly; jumping FP and +B. Set at 40 psi.
Again, this is while running 2JZ vvti coils from an IS300. Plugs and wires are brand new NGK. Plugs are BKR6E gapped to 028".
TPS has been checked and calibrated according to the TSRM. Everything is in spec except for one reading, which I'll have to go and pull from one of my posts earlier in the thread.
I've set timing twice, and both times at 10*. However there were still some issues at those times, so I suppose a third couldn't hurt.
http://www.supramania.com/forums/showthread.php?52217-IGNITER-GROUND...-crispics
Reset fuel pressure again, this time correctly; jumping FP and +B. Set at 40 psi.
Again, this is while running 2JZ vvti coils from an IS300. Plugs and wires are brand new NGK. Plugs are BKR6E gapped to 028".
TPS has been checked and calibrated according to the TSRM. Everything is in spec except for one reading, which I'll have to go and pull from one of my posts earlier in the thread.
I've set timing twice, and both times at 10*. However there were still some issues at those times, so I suppose a third couldn't hurt.
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Pretty simple. I've swapped between the 2JZ COP and stock coil setup twice now. The car has run the same with both setups.
Quick update:
The break up I had been experiencing at 3500 RPM was under very light load and light throttle (~25-35%). Against my better judgement, I decided to try giving it a bit more throttle to place greater load on the engine when revving to and past the 3500 range. With greater throttle (~50%) and load, no break up occured. This makes me wonder if it's tune related, to which point the engine is running extremely rich under light throttle. I suppose it could also be a boost leak. If all goes well I'll be installing a wideband O2 sensor tonight and can get a better idea of what's actually going.
I've been reading VF (Vf1 > volt meter > ground) and while adjustments with the MAFT create physical/audible changes in the way the engine runs, the VF signal seems to be unaffected. From my observations, the VF signal has five readings: 0.0xx volts, 1.0xx volts, 2.2xx volts, 3.5xx volts, and 4.9xx volts. The readings vary across this range, most commonly when either under throttle or lifting completely (goes from 2.2-4.9 while under throttle to 0.0xx when completely off the throttle). At idle, the reading has been any one of those five. Again, adjusting the Idle dial on the MAFT seems to change the way the engine runs, however the adjustments don't seem to have any direct effect on the Vf readings.
Quick update:
The break up I had been experiencing at 3500 RPM was under very light load and light throttle (~25-35%). Against my better judgement, I decided to try giving it a bit more throttle to place greater load on the engine when revving to and past the 3500 range. With greater throttle (~50%) and load, no break up occured. This makes me wonder if it's tune related, to which point the engine is running extremely rich under light throttle. I suppose it could also be a boost leak. If all goes well I'll be installing a wideband O2 sensor tonight and can get a better idea of what's actually going.
I've been reading VF (Vf1 > volt meter > ground) and while adjustments with the MAFT create physical/audible changes in the way the engine runs, the VF signal seems to be unaffected. From my observations, the VF signal has five readings: 0.0xx volts, 1.0xx volts, 2.2xx volts, 3.5xx volts, and 4.9xx volts. The readings vary across this range, most commonly when either under throttle or lifting completely (goes from 2.2-4.9 while under throttle to 0.0xx when completely off the throttle). At idle, the reading has been any one of those five. Again, adjusting the Idle dial on the MAFT seems to change the way the engine runs, however the adjustments don't seem to have any direct effect on the Vf readings.
Unplug the TPS and see if the "miss" goes away. I had this happen, and another person I know with a MkT had the same thing happen. The TPS gets an intermittent connection between IDL and E2, so for a moment, it hits FCO at RPM above about 2,000. If you disconnect the TPS, it doesn't happen. If this makes the miss go away, replace the TPS.
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This miss is completely gone. The only issues I am now having with the car are break-up directly at 3500 rpm, regardless of throttle/load/boost, and a very low idle.
I haven't heard of it happening on the 7M, but on the 1JZ removing the fuel-dampener (which I see you have removed) causes this type of problem. The dampener de-Q's the fuel rail, without it it can resonate at certain frequencies resulting in large pressure variations along its length. Try putting it back on if you still have it.
Hrmm... I hate to do that, but I believe I still have a dampener so if some of my further diagnostics don't sort it out then I'll go ahead and try it.
Do you think that such a harmonic would be seen via a fuel pressure gauge? Perhaps a fluttering of the needle because of the pulses being produced? I'll try taking a look next time I get outside.
*edit*
Because the initial issues that this thread was written for have been resolved, I have created a new thread so that the information within this one remains more searchable and relevant to the thread topic. The new thread regarding breaking up at 3500 RPM can be found here:
http://www.supramania.com/forums/sh...egardless-of-Load-Boost&p=1827123#post1827123
Thanks again to everyone who has helped to diagnose these issues.
CLIFFS:
Misfire due to loose injector connector.
Code 52 due to disconnected rear Knock Sensor connector.
When troubleshooting an issue with a vehicle, always practice the KISS method! Keep It Simple, Stupid!
Do you think that such a harmonic would be seen via a fuel pressure gauge? Perhaps a fluttering of the needle because of the pulses being produced? I'll try taking a look next time I get outside.
*edit*
Because the initial issues that this thread was written for have been resolved, I have created a new thread so that the information within this one remains more searchable and relevant to the thread topic. The new thread regarding breaking up at 3500 RPM can be found here:
http://www.supramania.com/forums/sh...egardless-of-Load-Boost&p=1827123#post1827123
Thanks again to everyone who has helped to diagnose these issues.
CLIFFS:
Misfire due to loose injector connector.
Code 52 due to disconnected rear Knock Sensor connector.
When troubleshooting an issue with a vehicle, always practice the KISS method! Keep It Simple, Stupid!
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