running rich bad 02 sensor?

Motleyzo6

Member
Joined
Nov 18, 2014
just got this car recently and when i start it up it smells rich which i feel is normal for the chip thats in it, but after 5-7 min of idle time it starts smoking a whitish blueish and gray when i rev it a little, and the fumes and raw unburnt fuel will kill you in a matter of minutes, at first i was thinking oil from exhaust side of turbo but want to rule that out for now, im wondering if the 02 is bad and the ecm is dumping fuel in to compensate, scanmaster milivolts were 525-710 at idle fully warmed up, blm was 130, so far i have checked for vacuum leaks and thats all good, no exhaust leaks, pcv valve ok and working, fuel press 43psi, checked intake and plenum bolts all are tight, also pulled plugs to inspect, they are very dark like a rich condition but no signs of oil on them, any ideas of where to look or check will be great.

mods are ta 49
TT93 alky chip
lt1 maf/translator
tr6 ignition
 
just got this car recently and when i start it up it smells rich which i feel is normal for the chip thats in it, but after 5-7 min of idle time it starts smoking a whitish blueish and gray when i rev it a little, and the fumes and raw unburnt fuel will kill you in a matter of minutes, at first i was thinking oil from exhaust side of turbo but want to rule that out for now, im wondering if the 02 is bad and the ecm is dumping fuel in to compensate, scanmaster milivolts were 525-710 at idle fully warmed up, blm was 130, so far i have checked for vacuum leaks and thats all good, no exhaust leaks, pcv valve ok and working, fuel press 43psi, checked intake and plenum bolts all are tight, also pulled plugs to inspect, they are very dark like a rich condition but no signs of oil on them, any ideas of where to look or check will be great.

mods are ta 49
TT93 alky chip
lt1 maf/translator
tr6 ignition

I just replaced mine with a heated one, because of the running rich and carbon monoxide smell, just replace it yesterday so have not driven it, only test drove it but seemed 100 percent better and carbon monoxide smell was gone.


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Make sure to replace it with a Denso 02 sensor, Delco’s leave a bit to be desired.
Installed a Delco last year and got all of 500 miles out of it, waited a couple days and ordered a Denso, 2700 + miles and still good.
 
Put in a denso and still no difference, rich as hell, now I’m leaning towards that it’s dumping in too much fuel, maybe bad injector, bad FPR, or previous owner gave Eric the wrong info when he had the chip made, thought blm were locked at 128 my scanmaster shows 136, I’ll post up my scanmaster numbers later today after I’m done looking things over
 
The o2 number is not rich nor does the fuel correction show any drastic measures.

Pull the downpipe and see if the exhaust turbine is wet.
 
my scanmaster numbers this is after new denso sensor ecm reset and about 15-20 minute idle time, and was smoking out the pipes, again a whiteish,blueish grayish smoke. also compression test and leakdown were also done yesterday all came back 148-150 and leakdown was 5-8% on all cylinders,replaced plugs as well, ill attact some pics of the old plugs

02 milivolts 680-750
l8 30
af 04
bat 13.9
ine 128
blm 136
mph 00
clt 172
ats 97
r 875
tps .42
iac 29
mal oo
 

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Spray start fluid around the throttle body, and the plenum gasket area. Same around the injs.
If no results, it may be time to flow check the injs.
Is the inj harness still wrapped in close to the base of the EGR valve? If it's original, it may be cooked there, and the adjacent inj is on.
Translator settings good?
 
Spray start fluid around the throttle body, and the plenum gasket area. Same around the injs.
If no results, it may be time to flow check the injs.
Is the inj harness still wrapped in close to the base of the EGR valve? If it's original, it may be cooked there, and the adjacent inj is on.
Translator settings good?
 
translator settings are good as far as i know, inj harness is fairly new, does no longer have an EGR valve, and yes i did spray around those areas, ill spray again to double check.
 
I would look for pre 02 exhaust leak. Rig up a shop vac to the tail pipe. Plug the hose into the exhaust port of the vacuum. Use soapy water in a spray bottle on the headers and flamges.
 
I would look for pre 02 exhaust leak. Rig up a shop vac to the tail pipe. Plug the hose into the exhaust port of the vacuum. Use soapy water in a spray bottle on the headers and flamges.
no exhaust leaks, already double and triple checked that
 
Make sure to replace it with a Denso 02 sensor, Delco’s leave a bit to be desired.
Installed a Delco last year and got all of 500 miles out of it, waited a couple days and ordered a Denso, 2700 + miles and still good.
I was having issues with my Delco O2 sensor reading low 400 and I installed a new Denso today and my O2's are back up around 775.
 
translator settings are good as far as i know, inj harness is fairly new, does no longer have an EGR valve, and yes i did spray around those areas, ill spray again to double check.

Have heard of more than 1 instance, where the leak was on a newly installed plenum gasket. The leak was directly under the t/b. 30+ y/o, and things tend to get warped. Being there is no fastener on the ft of the plenum, it's prime territory for a leak.
 
Have heard of more than 1 instance, where the leak was on a newly installed plenum gasket. The leak was directly under the t/b. 30+ y/o, and things tend to get warped. Being there is no fastener on the ft of the plenum, it's prime territory for a leak.
All that you mention is good, guess now I’m leaning towards turbo oil seal causing the smoke
 
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