Lack of power/transmission issues

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the_hoe

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Quite confused on current issue with the car, for background it is a 1999 4wd 4 door tahoe, currently has headers, cat delete, rear o2 delete, egr delete, corvette servo, cut the restrictor plate off the throttle blade, and a tune from blackbear, im currenty experiencing a loss of power / lack of shifting, confused of which it might be for following reasons, one is i am constantly burning up spark plug wires due to the added heat from the headers even though they are kept from touching the headers, but i also have a p1870 code, and the other thing is that i am still getting codes for the rear o2s even though they should be deleted out of the system, and the front o2s are getting codes as well since they are brand new, unsure what course of action I should take, as i dont know if one these issues could be causing all the problems, drove fine for about 2 days until all of these symptoms came up, any insight would be greatly appreciated.
 
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the_hoe

the_hoe

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meant to say the front o2s are getting codes but should not be since they are new, my apologies
 

east302

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The P1870 is set when excessive torque converter clutch slippage is detected. If you have a tech2 or similar scanner, GM does have the diagnostic procedures for it.

Images below are from a 1998 manual, unsure if there were any significant changes for 1999 but maybe it will help. Another source (alldatadiy.com which has the same info/diagrams as the GM manual) notes that a faulty “Transmission Fluid Pressure (TFP) manual valve position switch” may trip the same code.

It probably wouldn’t hurt to drop the pan and see how it looks in there.

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the_hoe

the_hoe

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The P1870 is set when excessive torque converter clutch slippage is detected. If you have a tech2 or similar scanner, GM does have the diagnostic procedures for it.

Images below are from a 1998 manual, unsure if there were any significant changes for 1999 but maybe it will help. Another source (alldatadiy.com which has the same info/diagrams as the GM manual) notes that a faulty “Transmission Fluid Pressure (TFP) manual valve position switch” may trip the same code.

It probably wouldn’t hurt to drop the pan and see how it looks in there.

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appreciate the info, however, i recently went out to mess with it again because i find it hard to just leave things alone, while doing so it struggles to even get up to speed, the exhaust is spitting fluid and there is a tick sound coming from the engine, so i think I might have an entirely different problem on my hands, bad rocker maybe? or is it just a severe misfire?
 

east302

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Are there any misfire counts or P030# codes?

I’d start with the basics - fuel pressure KOEO, good and comparable spark at all eight and compression test.

It could just be a bad distributor cap or wire, so I’d check the spark first.

If the symptoms are present at idle, then the transmission code could probably be set aside for now.
 

exp500

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If you have been burning plug wires off, your cap likely burned too.
I agree with scan it again.
Taylor has some pretty good sleeves and looms that should work well for you.
 

Chavivi5555

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Quite confused on current issue with the car, for background it is a 1999 4wd 4 door tahoe, currently has headers, cat delete, rear o2 delete, egr delete, corvette servo, cut the restrictor plate off the throttle blade, and a tune from blackbear, im currenty experiencing a loss of power / lack of shifting, confused of which it might be for following reasons, one is i am constantly burning up spark plug wires due to the added heat from the headers even though they are kept from touching the headers, but i also have a p1870 code, and the other thing is that i am still getting codes for the rear o2s even though they should be deleted out of the system, and the front o2s are getting codes as well since they are brand new, unsure what course of action I should take, as i dont know if one these issues could be causing all the problems, drove fine for about 2 days until all of these symptoms came up, any insight would be greatly appreciated.
Hello. First of all sorry because I don't speak English and I use the translator to write. I am a Spaniard living in Colombia and I have a 1997 Chevy Tahoe 4x4, 4 doors. I have had a similar problem for a long time, the car had no power and vibrated a lot. I discovered that the number 1 cylinder was not working properly and that was the cause. After many checks the problem was in the connector that brings power to the injectors. When inserting the connector, one of the pins did not insert and moved up when inserting the connector, so sometimes it made contact and sometimes it did not. By making the pin insert correctly the car has returned to working perfectly. Hope this helps and sorry for the translation.
 

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