Cold Start Rough Idle - Page 2

El Supracabras · 06-01-2011, 05:38 PM

Yes, the gte uses a wasted spark ignition. The ge uses one coil connected to a distributor cap. I know 1 and 6 share a coil but dont remember the order of the rest. Its posted in numerous places. There are tests to determine a bad coil in the tsrm. You can sometimes spot tiny cracks in the plastic and epoxy on them if you just take them off and look closely at them. I've even seen the plastic surrounding the connector terminal crack and corrode inside causing intermittent misfires.
Have you checked the timing? I've noticed on many cars that prior owners/mechanics will adjust the timing to mask other problems (vacuum leaks, tune up, bad sensors,etc.), so when you start fixing those problems the timing sometimes winds up needing adjustment. My opinion is, it's always a good idea (though not always necessary) to check timing after repairing things relevant to drivability issues. Try checking it, it's free and who knows, you might get lucky.

ochowdero · 06-02-2011, 06:08 AM

same happened to me,
i replaced the bvsv (becuz mine was cracked, maybe this is happening to you?{its located right above the radiator, to the left if your facing the engine)
its part number 23262
http://www.cygnusx1.net/Supra/Librar...spx?F=1708&P=3
you can get this from driftmotion.com or rock auto.

i did that and it still didnt work...
i noticed my valve covers were leaking...BAM.. did a valve repair job and im on my way...

hope this helps..
also if this is an automatic car then your syncros? may be bad...people rule that out but honestly even with the valve cover repair and the bvsv it still did it abit...i did an auto to manual and i dont have that problem anymore.

916MKIIIx2 · 06-01-2011, 04:33 PM

Ok, So I put in the fuel filter and it helped, but did not fix the rough idle on start up. So I pulled out all the spark plug wires again took them up to wyotech and tested them, all came back good, tested all my spark plugs also came back good at both places I tested them. So I said fuck it, since I had one extra spark plug, started with replacing cylinder #1 spark plug, still rough idled, then moved the good plug to cylinder #6, rough idle went away but now I can really feel the miss fire, I almost want to say its inconsistently missing 2 cylinders... Coil pack? If I remember correctly the coil packs are 1 per 2 cylinders, get back to me please, the problems almost fixed!

06-02-2011, 06:08 AM	#2
ochowdero 12psi boost Join Date: Jun 2010 Location: California Posts: 277	same happened to me, i replaced the bvsv (becuz mine was cracked, maybe this is happening to you?{its located right above the radiator, to the left if your facing the engine) its part number 23262 http://www.cygnusx1.net/Supra/Librar...spx?F=1708&P=3 you can get this from driftmotion.com or rock auto. i did that and it still didnt work... i noticed my valve covers were leaking...BAM.. did a valve repair job and im on my way... hope this helps.. also if this is an automatic car then your syncros? may be bad...people rule that out but honestly even with the valve cover repair and the bvsv it still did it abit...i did an auto to manual and i dont have that problem anymore. __________________ 1987 supra, BLUE 7mge.. AUTO TO MANUAL SWAP.. i really want turbo

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06-01-2011, 05:38 PM	#1
El Supracabras 3" Exhaust Join Date: Feb 2010 Location: Chicago Posts: 240	Yes, the gte uses a wasted spark ignition. The ge uses one coil connected to a distributor cap. I know 1 and 6 share a coil but dont remember the order of the rest. Its posted in numerous places. There are tests to determine a bad coil in the tsrm. You can sometimes spot tiny cracks in the plastic and epoxy on them if you just take them off and look closely at them. I've even seen the plastic surrounding the connector terminal crack and corrode inside causing intermittent misfires. Have you checked the timing? I've noticed on many cars that prior owners/mechanics will adjust the timing to mask other problems (vacuum leaks, tune up, bad sensors,etc.), so when you start fixing those problems the timing sometimes winds up needing adjustment. My opinion is, it's always a good idea (though not always necessary) to check timing after repairing things relevant to drivability issues. Try checking it, it's free and who knows, you might get lucky.

06-01-2011, 04:33 PM	#3
916MKIIIx2 3" Exhaust Join Date: Nov 2008 Location: California Posts: 152	Ok, So I put in the fuel filter and it helped, but did not fix the rough idle on start up. So I pulled out all the spark plug wires again took them up to wyotech and tested them, all came back good, tested all my spark plugs also came back good at both places I tested them. So I said fuck it, since I had one extra spark plug, started with replacing cylinder #1 spark plug, still rough idled, then moved the good plug to cylinder #6, rough idle went away but now I can really feel the miss fire, I almost want to say its inconsistently missing 2 cylinders... Coil pack? If I remember correctly the coil packs are 1 per 2 cylinders, get back to me please, the problems almost fixed!