SES Light

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   So my 4.9 swapped 86 gt is giving me some weird annoyances. When i 

start the car, no matter what situation, after the idle starts going down so 

maybe 20-30 seconds after start, i get an ses light and exactly when it 

comes on the idle raises about 75 or 100 rpms... its strange. When i try 

checking codes the ses light turns off the very second i plug in the aldl 

connector to the computer... so i cant read the code. Also it seems to run 

better on open loop, and when it is in closed loop it feels like someone 

retarded the timing a couple degrees, just a very slight loss of power, 

hardly noticeable though. Also when its cold...ish (half or less operating 

temp) there is a dramatic loos of power when in top gear and WOT, while 

in 4th you can floor it and then start letting off a big and you feel it 

accelerating more and more the less your in the throttle, it seems like half 

throttle is quickest, clutch slippage? non heated o2 fail? ive got nothing. 

Help would be nice.   

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orange Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 15 September 2010 Location: United States Status: Offline Points: 106	Post Options Post Reply Quote orange Report Post Quote Reply Topic: SES Light Posted: 07 June 2011 at 10:03pm
	So my 4.9 swapped 86 gt is giving me some weird annoyances. When i start the car, no matter what situation, after the idle starts going down so maybe 20-30 seconds after start, i get an ses light and exactly when it comes on the idle raises about 75 or 100 rpms... its strange. When i try checking codes the ses light turns off the very second i plug in the aldl connector to the computer... so i cant read the code. Also it seems to run better on open loop, and when it is in closed loop it feels like someone retarded the timing a couple degrees, just a very slight loss of power, hardly noticeable though. Also when its cold...ish (half or less operating temp) there is a dramatic loos of power when in top gear and WOT, while in 4th you can floor it and then start letting off a big and you feel it accelerating more and more the less your in the throttle, it seems like half throttle is quickest, clutch slippage? non heated o2 fail? ive got nothing. Help would be nice.
	Orange 4.9

Romeo Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033	Post Options Post Reply Quote Romeo Report Post Quote Reply Posted: 08 June 2011 at 10:00pm
	Could also be a fuel issue (If the fuel can't keep up with the air, it'll make more power at mid-throttle than at full) or a MAF fault (If it gets covered in oil, it wont read the air rushing past, and more air will only over-richen the mixture). This could be a fun one to figure out.
	Never shift into reverse without a back-up plan.

orange Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 15 September 2010 Location: United States Status: Offline Points: 106	Post Options Post Reply Quote orange Report Post Quote Reply Posted: 10 June 2011 at 12:29am
	I though it was fuel too, but i have above 40psi at any rpm under any load. And i dont have a MAF i have a MAP, if that changes your thoughts. and remember it only does it when coldish
	Orange 4.9

Romeo Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033	Post Options Post Reply Quote Romeo Report Post Quote Reply Posted: 10 June 2011 at 10:14pm
	Well, cold air is more dense, and will cool a MAF quicker, but obvious that whole theory goes to hell if you don't have one. Back on topic though, I think it's safe to say the fault is a sensor related one, not a mechanical one (So I doubt it's clutch slippage), due to the fact the fault "resolves" itself when in open-loop. Forgive me, it's been a while since I've used a ALDL scan-tool, but can you look at sensor voltages with it? If so, keep them open, and check your readings at various loads.
	Never shift into reverse without a back-up plan.

Bassman Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Sir Brian Joined: 12 February 2007 Location: Canada Status: Offline Points: 2501	Post Options Post Reply Quote Bassman Report Post Quote Reply Posted: 11 June 2011 at 8:22am
	I am concsidering this polisher (kit) until my trans blew up...may take a trip South and pick it up. http://www.griotsgarage.com/product/car+care/car+polishing/o rbitals+and+car+polishing+tools/griot%27s+garage+random+orbi tal.do
	Brian (Bassman) 86 GT Fastback 3.2L 2013 Mazda3 Sport GS SkyActive [IMG]http://i170.photobucket.com/albums/u243/Bassman68/BassmanSignature.png">

orange Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 15 September 2010 Location: United States Status: Offline Points: 106	Post Options Post Reply Quote orange Report Post Quote Reply Posted: 11 June 2011 at 11:33pm
	Yes i can read almost all sensors, i just dont know what to look for.
	Orange 4.9

Romeo Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033	Post Options Post Reply Quote Romeo Report Post Quote Reply Posted: 12 June 2011 at 12:00am
	Anything that doesn't make sense under the condition. As throttle gets opened more, MAP should increase, injector pulse should increase, oxygen sensor should go up and stay up (At WOT). Easiest bet to start with would be to check the O2 readings and see what's going on when you step on it (Is it leaning out? Puking fuel?)
	Never shift into reverse without a back-up plan.

orange Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 15 September 2010 Location: United States Status: Offline Points: 106	Post Options Post Reply Quote orange Report Post Quote Reply Posted: 12 June 2011 at 12:29pm
	Ok ill do some tests, i though it might be a funny o2 but its brand new and acdelco, when i blip the throttle sometime it states lean for the second i hit the gas. Ill get back with some tests though
	Orange 4.9

orange Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 15 September 2010 Location: United States Status: Offline Points: 106	Post Options Post Reply Quote orange Report Post Quote Reply Posted: 13 June 2011 at 12:33am
	Ok so no data yet, i tore the engine apart and such. And made an interesting discovery, all except 2 or my exhaust valve stems are white, but the back side of the valve is dark brown black. I know white valves are either lean, race gas, or fuel additives, but mine are just white stems. and my spark plugs looked normal but most or the cores were a light grey maybe white, and the two cylinders that didnt have white exhaust valve stems had black plugs. Any thoughts?
	Orange 4.9

Romeo Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033	Post Options Post Reply Quote Romeo Report Post Quote Reply Posted: 13 June 2011 at 8:23am
	Well, it could be that you're burning oil in the two, which the O2 is seeing as rich, and is consequently leaning out the other cylinders. Could also be something alot simpler that I haven't thought of yet. lol
	Never shift into reverse without a back-up plan.