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Discussion Starter #1
Hey guys been awhile since ive been on here. I was out today and had a spirited run nothing crazy but i usually drive it easy. Its my dd. I had alot of white smoke under hard throttle. I have 100k on car headers,cam,cai etc. When i drive regular nothing, car runs great other wise. Any ideas? What should i check first, i use mobile 1 synth, every 4000 miles. Did radiator fluid 6 months ago. No leaks under car at all.:huh: Should i have a compression test ,leak test etc?
 

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is the smoke coming from the exhaust or under the hood
 

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Discussion Starter #3
Sorry its coming out the exhaust only. White
 

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you prob wont wanna hear it, but that is pretty much a guarantee of coolant leaking into the cylinders....from either a blown head gasket, cracked head, or cracked block.
 

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If there is no loss in radiator fluid then the tune stinks and is way too lean.
Get a good OBD scanner recorder and only have a pro tuner look at that data as if too lean you'll do cylinder or valve damage.
 

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Discussion Starter #6
Cracked block,blown head gasket???:thud: The car runs great though. I checked the radiator and it hasnt used a drop in 6 months since i had it changed. The oil is like a gold honey not milky. I also forgot to mention i do get the codes that started to come up about the 02 sensors. I have lg longtubes they had the rear o2's up front and none in the rear at all as i have no cats. The car does need to be retune when i have the air on and slow down if im in neutral the idle surges up and down like nuts and will then stabilize. How much should a compression test run to check cylinders? and what should they be?
 

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how many miles are on it since you did the h/c and had it tuned?

does it smoke all the time, or under certain driving conditions?

compression test is ok, but a leakdown test would be more accurate. if you are not having a loss of any coolant, than I would not worry about a blown head gasket, cracked block/head.

when was the last time you had your fuel system cleaned- fuel filter, injectors, ect? if they are dirty/clogged it could be causing a lean condition.
 

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Discussion Starter #8
how many miles are on it since you did the h/c and had it tuned?

does it smoke all the time, or under certain driving conditions?

compression test is ok, but a leakdown test would be more accurate. if you are not having a loss of any coolant, than I would not worry about a blown head gasket, cracked block/head.

when was the last time you had your fuel system cleaned- fuel filter, injectors, ect? if they are dirty/clogged it could be causing a lean condition.
No it doesnt do it under normal driving just under wot. No power loss runs like a bandit.

40,000 miles since i had last fuel system cleaned. hasnt been tuned since 2 years ago. I like were your going i know it does need the fuel system done great suggestion. Im changing the 02s next weekend i think ill change the fuel filter also. What do i need to do to clean the fuel system properly. My dad is an old school mech, and has lots of tools. Then ill have it retuned.
 

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if it has just recently started, i would be hard pressed to blame the tune since it has 40k on it.

skip the fuel system cleaners that you pour in your tank- they are marginal at best. There are several kits available that hook to the schrader valve on the fuel rail- these are far more effective. What I do is I pull the rails/injectors off and bench clean them. I have a cleaning station set up for injectors complete with electrical connectors for them. I run cleaning solvent thru them like that under pressure until the flow is uniform again.

knowing sensor readings under WOT would also be handy- your computer might be intentionally creating a lean condition due to sensor inputs. Sensors such as IAT, O2, MAF can all contribute to creating an excessively lean condition.
 

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Discussion Starter #10
if it has just recently started, i would be hard pressed to blame the tune since it has 40k on it.

skip the fuel system cleaners that you pour in your tank- they are marginal at best. There are several kits available that hook to the schrader valve on the fuel rail- these are far more effective. What I do is I pull the rails/injectors off and bench clean them. I have a cleaning station set up for injectors complete with electrical connectors for them. I run cleaning solvent thru them like that under pressure until the flow is uniform again.

knowing sensor readings under WOT would also be handy- your computer might be intentionally creating a lean condition due to sensor inputs. Sensors such as IAT, O2, MAF can all contribute to creating an excessively lean condition.
OOK now were talking. Ive been wanting to do the fuel system anyway. I agree i want to do it thorough not that bs pour in the tank ****. just checked oil again, a little low. Would an oil catch can be any help?
 

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a catch can is never a bad idea imo. excessive oil consumption can trick the computer into thinking it is running rich therefor leaning out the mixture, but I have not seen it result in that much of a lean condition.
 

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a catch can is never a bad idea imo. excessive oil consumption can trick the computer into thinking it is running rich therefor leaning out the mixture, but I have not seen it result in that much of a lean condition.
Ok so changing o2's an fuel filter, and fuel system cleaning first, maybe a tune to see whats going on with computer?
 

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Cracked block,blown head gasket???:thud: The car runs great though. I checked the radiator and it hasnt used a drop in 6 months since i had it changed. The oil is like a gold honey not milky. I also forgot to mention i do get the codes that started to come up about the 02 sensors. I have lg longtubes they had the rear o2's up front and none in the rear at all as i have no cats. The car does need to be retune when i have the air on and slow down if im in neutral the idle surges up and down like nuts and will then stabilize. How much should a compression test run to check cylinders? and what should they be?
The tune is the cause and over time with it has caused excess carbon buildup that also effects the front 02 sensors.
Also 02s really work best with no more then 30,000 miles on them, longer then that and 02s get lazy

Your 02 codes could be anything from bad tune not taking care of having no rear 02s or the fact those headers cause front 02s to be located further downstream and with a bad tune over time the long term negative effects are seen.

If it was a leak then it would have been seen in both oil and water.

If fuel rail pressure is at 58 PSI it is not a pump or filter.

Check tune first, else injectors are too small for that engine but if injector was bad you'd be getting high lean most of the time, lots of ping and misfire.
 

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Discussion Starter #14
The tune is the cause and over time with it has caused excess carbon buildup that also effects the front 02 sensors.
Also 02s really work best with no more then 30,000 miles on them, longer then that and 02s get lazy

Your 02 codes could be anything from bad tune not taking care of having no rear 02s or the fact those headers cause front 02s to be located further downstream and with a bad tune over time the long term negative effects are seen.

If it was a leak then it would have been seen in both oil and water.

If fuel rail pressure is at 58 PSI it is not a pump or filter.

Check tune first, else injectors are too small for that engine but if injector was bad you'd be getting high lean most of the time, lots of ping and misfire.
Thank you so much guys for info. Ill try to get in to get tune this week, im going to change 02's at same time and fuel filter.
 
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