Issues - Help?
02-12-2009, 09:21 AM
#1
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Issues - Help?
So.. the car has been pretty much been parked since my dyno/tuning day (2 months of real sitting though). It's been started and run once in awhile, but the important thing to know is that nothing on the .MSQ has changed.
Anyway here's the scenario:
I gave it an oil change, and decided to drive it this week. The car is stumbling hard into boost and misfiring. Pulled the plugs, changed them. Pulled some MS logs, but it does not appear to be a tuning issue, as my map was just tuned.
Here's what's noticeable:
1> The car starts and idles fine with perfect AFR, will run fine through a normal out of boost 1st gear pull.
2> The biggest change: The car seems to go crazy lean when I punch it (transition to boost), but runs fine under normal load (out of boost). It also seems to be a bit leaner across the board in general, but specifically in boost. (13.1 when it was 11.8-12ish during tuning)
3> The RPM pickup is going a bit nuts (log attached), but can't tell if that is recent.
Some things to know:
1> The fuel filter and pump were changed at the same time (about a year and a half ago)
Setup:
1.6
MSq
550s (rx7)
gt2871
Toyota COPS
Walbro 190.
I'm pretty much open to anything at this point... fire away.
Anyway here's the scenario:
I gave it an oil change, and decided to drive it this week. The car is stumbling hard into boost and misfiring. Pulled the plugs, changed them. Pulled some MS logs, but it does not appear to be a tuning issue, as my map was just tuned.
Here's what's noticeable:
1> The car starts and idles fine with perfect AFR, will run fine through a normal out of boost 1st gear pull.
2> The biggest change: The car seems to go crazy lean when I punch it (transition to boost), but runs fine under normal load (out of boost). It also seems to be a bit leaner across the board in general, but specifically in boost. (13.1 when it was 11.8-12ish during tuning)
3> The RPM pickup is going a bit nuts (log attached), but can't tell if that is recent.
Some things to know:
1> The fuel filter and pump were changed at the same time (about a year and a half ago)
Setup:
1.6
MSq
550s (rx7)
gt2871
Toyota COPS
Walbro 190.
I'm pretty much open to anything at this point... fire away.
Last edited by Newbsauce; 02-12-2009 at 09:36 AM.
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02-12-2009, 09:41 AM
#4
I had the same problem with a misfire under boost. It would run fine up the rpm band w/o boost. Swapped out the newish no-name autozone wires for some used NGK blues and it solved the problem. Maybe the similar problem with RPM issues might indicate something in the ignition - like the cops or wiring. 
There are loads of toyotas/lexus that use those cops. You could swap out a know good one for each cylinder. That's how I found a bad cop on my RX300.
There are loads of toyotas/lexus that use those cops. You could swap out a know good one for each cylinder. That's how I found a bad cop on my RX300.
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02-12-2009, 09:48 AM
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I had the same problem with a misfire under boost. It would run fine up the rpm band w/o boost. Swapped out the newish no-name autozone wires for some used NGK blues and it solved the problem. Maybe the similar problem with RPM issues might indicate something in the ignition - like the cops or wiring. There are loads of toyotas/lexus that use those cops. You could swap out a know good one for each cylinder. That's how I found a bad cop on my RX300.
There are loads of toyotas/lexus that use those cops. You could swap out a know good one for each cylinder. That's how I found a bad cop on my RX300.This is a log from my dyno day....
Look at the RPM vs RPM100 on this versus the log I took yesterday.
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02-12-2009, 10:51 AM
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That was pre-dyno day had a coolant bursting issue, as well as the rain issue... should not really be a factor here. Either way, here's the picture of the plugs 
1-4 from left to right. Cyl 3 ftw.
1-4 from left to right. Cyl 3 ftw.
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02-12-2009, 11:37 AM
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Well the pump is fairly new.. can't be more then a year and a half or so and is just as loud as ever (Walbro 190hp). Would the car idle as well as it is with bad cops?
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02-12-2009, 02:20 PM
#16
Vash-
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02-12-2009, 02:22 PM
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lol.....think again. Any chance you have the FM hood? Thats why I sold mine. Water resting on the valve cover soaking the plugs and wires, corroding the contacts. I had similar issues and changed to regular NGK wires with new plugs, that solved my misfire. Then once I replaced my fuel pump I was back in business.
Vash-
Vash-
Flooded the valley. Either way, the plugs I'm posting are the ones I ran on the dyno (247 rhwp). They have since been changed to spanking new BKR7E -11.
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