fixed the running rich problem

djalkyd · 04-15-2006, 07:38 PM

well for a few weeks the car had been running extremely rich and everytime i started getting into boost, it would just puff out black smoke and want to die. the turbo would start spooling like crazy even befor one psi of boost was reached.

i went from getting 300+ miles to a tank to getting 130 miles a tank. the fuel was just dumping.

i thought it may have been the HAC sensor because the problem started when i went through the mountains going into los angeles from bakersfield. so if anyone knows that mountain range called "the grape vine" then you will understand what the car was put through.

as soon as i went through those mountains, i started getting real bad fuel cut in 5th gear. then a few days later it started happening in all gears. then a few days later it started running real rich and the gas consumpsion just went through the roof.

i started by checking the resistance in the afm and it checked out fine, but i didn't rule that out. i checked the injectors and ignition, everything was fine there. so i pulled the hac sensor and it was fine to.

it all boiled down to the afm. i replaced it with the upgraded LS400 of course and talk about a difference. the car just runs so much cleaner. the power is back in it even at stock boost. it's not eating so much fuel anymore.

so if your car starts putting around and just runs extremely rich, don't rule out the AFM.

and to supragirl, thanks you very much for all the wonderful advice. you rock.

ddmcse · 04-15-2006, 11:35 PM

do you have an Air/Fuel gauge?

djalkyd · 04-16-2006, 06:42 AM

no a/f guage yet. i will be dynoing the car next week at school to make sure everything is ok with it. then i will be adding the s-afc and 550cc injectors.

djalkyd · 05-02-2006, 05:18 AM

ok, so i am back to square one. i bought a stock afm and put it on and the car runs like crap again.

i put an adjustable fuel pressure regulator on it and have stock pressure dialed in. the timing is set at stock also.

here is what is happening.

if i take off slowly, the car is fine. if i get into the throttle a little more then the turbo starts to spool when it shouldn't and as soon as i start building any kind of boost up to 5psi, the car jerks and gets real sluggish, runs super rich and just feels like crap.

as soon as i put the lexus afm on then it runs kind of fine. if i am cruising around and start to build boost, as soon as i hit 1 psi, i feel a slight hesitation and a little sluggish but if i jam on the throttle, the turbo spools up real loud and the car goes but not like it did before this problem.

it seems like the turbo spools up when it shouldn't and it is extremely loud like a vacuum cleaner sucking at my ear. i have the k and n filter with the front of the air box cut out so maybe it is just a normal sound.

i checked the tps and it is fine, no boost leaks because i hold 5 psi just fine... or am i suppose to have 7psi? i dont know what the stock boost level is suppose to be.

i checked for vacuum leaks and i cant hear any. tomorrow i am checking the egr system to see if it may be clogged.

the car just feels so slow now.

any ideas, please help.

ddmcse · 05-02-2006, 10:56 AM

i would check the vsv switches on the intake side uner the intake
one is for fuel one is for egr

it's a simple conductivity test

Isphius · 05-02-2006, 11:53 AM

http://www.toyota-supra.info/forums/...ead.php?t=4448

It sounds like he is having the same problem. Im not very knowledgeable about turbos, but maybe you need to rebuild it? Because it sounds like the motor is running fine off boost. It could also be the wastegate stopped working and burned your turbo up. Or maybe your old afm went bad and caused something to break from too rich a mixture? and now thats why it seems the new one is bad too. That happens a lot, Sometimes you replace a part and it works fine, but you didnt fix it. And then it goes bad a few days or weeks later. Also did you see if you are leaking pressure/vaccum from anywhere? That will also cause a rich mixture, and sluggishness, and bad boost/power.

djalkyd · 05-04-2006, 04:31 AM

wow, how dumb do i feel... i am kind of embarrased to actually say what was really wrong with the car.

to make a long story short, i bought hard piping for the inner cooler from cool eeze and never installed the hard pipe from the turbo to inner cooler i just left it stock.

well the stock rubber piping had what i call a "ninja crack" in it. you know, a crack that is only there under boost. like a flap that opens up durring boost.

well this explains the rich problem, the excesive turbo spool up sound and the not so loud blow off valve.

i checked the piping so many times and neglected to check the stock piping at the turbo because i never took it off.

it is definately fixed now. i am back to 10psi of boost and the car is feeling extremely strong again.

thanks again to everyone who gave great advice.

04-15-2006, 07:38 PM	#1
djalkyd 3" Exhaust Join Date: Jan 2006 Location: sacramento ca. Posts: 55	fixed the running rich problem well for a few weeks the car had been running extremely rich and everytime i started getting into boost, it would just puff out black smoke and want to die. the turbo would start spooling like crazy even befor one psi of boost was reached. i went from getting 300+ miles to a tank to getting 130 miles a tank. the fuel was just dumping. i thought it may have been the HAC sensor because the problem started when i went through the mountains going into los angeles from bakersfield. so if anyone knows that mountain range called "the grape vine" then you will understand what the car was put through. as soon as i went through those mountains, i started getting real bad fuel cut in 5th gear. then a few days later it started happening in all gears. then a few days later it started running real rich and the gas consumpsion just went through the roof. i started by checking the resistance in the afm and it checked out fine, but i didn't rule that out. i checked the injectors and ignition, everything was fine there. so i pulled the hac sensor and it was fine to. it all boiled down to the afm. i replaced it with the upgraded LS400 of course and talk about a difference. the car just runs so much cleaner. the power is back in it even at stock boost. it's not eating so much fuel anymore. so if your car starts putting around and just runs extremely rich, don't rule out the AFM. and to supragirl, thanks you very much for all the wonderful advice. you rock.

04-15-2006, 11:35 PM	#2
ddmcse 500whp yet? Join Date: Jun 2005 Location: CT U.S.A. Posts: 966	do you have an Air/Fuel gauge? __________________ 300+ RW HP Dyno run, jdm,mod turbo,3"exh,electfan,greddyboost Blown HeadGasket info My Supra KiXGaS

05-02-2006, 10:56 AM	#5
ddmcse 500whp yet? Join Date: Jun 2005 Location: CT U.S.A. Posts: 966	i would check the vsv switches on the intake side uner the intake one is for fuel one is for egr it's a simple conductivity test __________________ 300+ RW HP Dyno run, jdm,mod turbo,3"exh,electfan,greddyboost Blown HeadGasket info My Supra KiXGaS

05-02-2006, 11:53 AM	#6
Isphius 500whp yet? Join Date: Nov 2005 Location: Long branch, NJ Posts: 1,006	http://www.toyota-supra.info/forums/...ead.php?t=4448 It sounds like he is having the same problem. Im not very knowledgeable about turbos, but maybe you need to rebuild it? Because it sounds like the motor is running fine off boost. It could also be the wastegate stopped working and burned your turbo up. Or maybe your old afm went bad and caused something to break from too rich a mixture? and now thats why it seems the new one is bad too. That happens a lot, Sometimes you replace a part and it works fine, but you didnt fix it. And then it goes bad a few days or weeks later. Also did you see if you are leaking pressure/vaccum from anywhere? That will also cause a rich mixture, and sluggishness, and bad boost/power. __________________ Yay the supra assistant is gone!!! WEEE!! Last edited by Isphius; 05-02-2006 at 11:55 AM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Running Rich! Help needed	mc_p0pe	MKIII Supra	13	05-23-2008 12:31 AM
Occasional black smoke running rich	gelwell	MKIII Supra	3	04-09-2008 06:35 PM
Running Sooooooo Rich! Help!	godgaveussid	MKIII Supra	4	08-29-2007 08:46 PM
Running very rich	OmeGa	MKIII Supra	3	12-09-2006 09:59 PM
Running rich!	grygst76	MKIII Supra	6	09-29-2006 01:56 AM

04-16-2006, 06:42 AM	#3
djalkyd 3" Exhaust Join Date: Jan 2006 Location: sacramento ca. Posts: 55	no a/f guage yet. i will be dynoing the car next week at school to make sure everything is ok with it. then i will be adding the s-afc and 550cc injectors.

05-02-2006, 05:18 AM	#4
djalkyd 3" Exhaust Join Date: Jan 2006 Location: sacramento ca. Posts: 55	ok, so i am back to square one. i bought a stock afm and put it on and the car runs like crap again. i put an adjustable fuel pressure regulator on it and have stock pressure dialed in. the timing is set at stock also. here is what is happening. if i take off slowly, the car is fine. if i get into the throttle a little more then the turbo starts to spool when it shouldn't and as soon as i start building any kind of boost up to 5psi, the car jerks and gets real sluggish, runs super rich and just feels like crap. as soon as i put the lexus afm on then it runs kind of fine. if i am cruising around and start to build boost, as soon as i hit 1 psi, i feel a slight hesitation and a little sluggish but if i jam on the throttle, the turbo spools up real loud and the car goes but not like it did before this problem. it seems like the turbo spools up when it shouldn't and it is extremely loud like a vacuum cleaner sucking at my ear. i have the k and n filter with the front of the air box cut out so maybe it is just a normal sound. i checked the tps and it is fine, no boost leaks because i hold 5 psi just fine... or am i suppose to have 7psi? i dont know what the stock boost level is suppose to be. i checked for vacuum leaks and i cant hear any. tomorrow i am checking the egr system to see if it may be clogged. the car just feels so slow now. any ideas, please help.

05-04-2006, 04:31 AM	#7
djalkyd 3" Exhaust Join Date: Jan 2006 Location: sacramento ca. Posts: 55	wow, how dumb do i feel... i am kind of embarrased to actually say what was really wrong with the car. to make a long story short, i bought hard piping for the inner cooler from cool eeze and never installed the hard pipe from the turbo to inner cooler i just left it stock. well the stock rubber piping had what i call a "ninja crack" in it. you know, a crack that is only there under boost. like a flap that opens up durring boost. well this explains the rich problem, the excesive turbo spool up sound and the not so loud blow off valve. i checked the piping so many times and neglected to check the stock piping at the turbo because i never took it off. it is definately fixed now. i am back to 10psi of boost and the car is feeling extremely strong again. thanks again to everyone who gave great advice.