Sucks.
Tonyrodz's Tahoe Build Thread
- Thread starter Tonyrodz
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Tonyrodz
Resident Resident
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Tonyrodz
Resident Resident
Shocker
MADE IN CHINA
MADE IN CHINA
Last edited:
97YukonNZ
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Man! That sux! I hate it when trades leave all their shit around. Wgat a pain
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Tonyrodz
Resident Resident
Yup, and it still has decent tread too! I wouldn't be so mad if it was bald-ish.
Get your tune and it can be bald in a matter of minutes.
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Tonyrodz
Resident Resident
Actually it doesn't have a problem doing that now. I actually have to restrain myself from burning rubber. It's so much fun tho!
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Tonyrodz
Resident Resident
Can anyone tell me what this means? Good or bad? This is for my van.
This is how bad the misfires are. Plugs? Wires? Can't be all coils.
This is how bad the misfires are. Plugs? Wires? Can't be all coils.
Instead of the misfire graph can you show the misfire counts?
We need to see the STFTs once they start counting; the O2 sensors need to warm up and get workin'.
Can you show both fuel trims (short and long) at idle, then at 2000 rpm?
Can you show both fuel trims (short and long) at idle, then at 2000 rpm?
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Tonyrodz
Resident Resident
It was warned up--drove for almost 1 hr. This was at my low idle, around 450 rpms. I can def get that tomorrow or Friday. So you'll need st/Lt at 2000 rpms? What does that misfire graph look like? The one you're talking about. Thx for your help too @Fless This van has been driving me crazy for years. It actually stalled on me driving through an intersection today, and it wouldn't restart. I heard the TC bang a few times today while driving. No trans codes tho.
Just numbers instead of the graph. Like "Cyl 1 = 35" "Cyl 2 = 13" etc. There seems to be an issue with higher misfires on cyl 1.
Rare that the instantaneous STFTs would be steady at 0; are your upstream O2 sensors working? Do you see a change in the STFTs?
If they continue at 0 then the LTFTs should eventually come down closer to that. LTFTs are an average of the STFT over a longer period of time. Seeing your LTFTs over +10% means that the ECM has been adding fuel for a while to compensate for a lean condition. Generally you want the sum of the ST and LT fuel trims to add up to something lower than 10%.
So if your STFT Bank 1 is 2%, and the LTFT for the same bank is 6%, 6+2= 8% which is generally acceptable.
Same issue if the sum of the same bank trims is negative. Goal is between -10% and +10%, but closer to 0 is best.
Seeing the trims at the higher rpm could help determine if there is a vacuum leak or something else.
EDIT: bump your idle up to 600 rpm or so for the low reading. That's a really low idle you have there.
Rare that the instantaneous STFTs would be steady at 0; are your upstream O2 sensors working? Do you see a change in the STFTs?
If they continue at 0 then the LTFTs should eventually come down closer to that. LTFTs are an average of the STFT over a longer period of time. Seeing your LTFTs over +10% means that the ECM has been adding fuel for a while to compensate for a lean condition. Generally you want the sum of the ST and LT fuel trims to add up to something lower than 10%.
So if your STFT Bank 1 is 2%, and the LTFT for the same bank is 6%, 6+2= 8% which is generally acceptable.
Same issue if the sum of the same bank trims is negative. Goal is between -10% and +10%, but closer to 0 is best.
Seeing the trims at the higher rpm could help determine if there is a vacuum leak or something else.
EDIT: bump your idle up to 600 rpm or so for the low reading. That's a really low idle you have there.
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Tonyrodz
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I've never changed the O2's. Bought it with 110k and it now has 151k. I do think both cats are partially clogged, one more then the other. I was actually going to hollow 1 out. Would that cause my issues?
Are you having driveability issues? If you think the cats are clogged it's a relatively simple procedure for a shop to check the in and out pressure to confirm.
Do you suspect one side more than the other? Which one?
Do you suspect one side more than the other? Which one?
Snowbound
Jim
Clogged cats wouldn’t cause this issue. You’d see low efficiency convertor code.
Could be a bad coolant temp sensor. If it’s staying in open loop there wouldn’t be any STFT data.
Could be a bad coolant temp sensor. If it’s staying in open loop there wouldn’t be any STFT data.
Snowbound
Jim
I hate that I can’t use Tapatalk anymore. Thought I got kicked off the forum early this morning.
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Tonyrodz
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I actually changed that, thinking that might've been the issue.
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Tonyrodz
Resident Resident
No more tapa crap.
Snowbound
Jim
Is there 2? One for gauge and one for ECM? See if it’s showing a reading with the scanner. The STFTs should be constantly adjusting based off pre-cat O2 sensors. Scan the O2 readings and coolant temp. Also see what the status says if it’s in closed loop or open.
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Tonyrodz
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I'll give it a shot. Afaik there's only 1 coolant temp sensor which is located on the ds head. How can you tell if it's open or closed loop? Will it say it?
