Installed Longtubes: HELP problems.
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From: I play with Sand!!
Installed Longtubes: HELP problems. The car is constantly popping and running rich after installing the Edelbrocks. I can cruise along slowly, but any major amounts of Throttle causes the car to buck and sputter. Seems like it is running extremely rich, but the o2's are reading just a little lean (-5 LTFT). Sometimes the when the is popping the LTFT are going rich (up to +4)
I need help. I can't get my tune from Diablo yet on my car until I get a USB to RS232 connector. He sent me a tune to Adjust for the Newer injectors. I had to run open headers for about 15 miles to get back to the house. The o2's are about 1 1/2 from the opening. Would this kill the O2's? Also I think I read somewhere that the Rear O2's from a vette are good to use for the Heatingissue I've read about.
I have o2 sims also.
I also posted this in the external section.
https://ls1tech.com/forums/showthrea...76#post2389876
I need help. I can't get my tune from Diablo yet on my car until I get a USB to RS232 connector. He sent me a tune to Adjust for the Newer injectors. I had to run open headers for about 15 miles to get back to the house. The o2's are about 1 1/2 from the opening. Would this kill the O2's? Also I think I read somewhere that the Rear O2's from a vette are good to use for the Heatingissue I've read about.
I have o2 sims also.
I also posted this in the external section.
https://ls1tech.com/forums/showthrea...76#post2389876
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At part throttle, the vacuum in your intake can suck exhaust backward (during cam overlap), which can can pull air back into the system. This can show a lean condition, cause backfiring etc. I would expect it to be anywhere upstream of the cats.
Loosely cover your exhaust outlets and look for a leak. The car will still run unless you absolutely completely block the exhaust. Check around your AIR fittings, all flanges, etc.
Loosely cover your exhaust outlets and look for a leak. The car will still run unless you absolutely completely block the exhaust. Check around your AIR fittings, all flanges, etc.
If I read your post correctly, you have bigger? injectors and you haven't put the new tune in your car yet, right?...well then you are running rich-maybe extremely rich depending on how big those injectors are...get that tune in the car, quick.
good luck.
good luck.
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Originally Posted by Richiec77
The car is constantly popping and running rich after installing the Edelbrocks. I can cruise along slowly, but any major amounts of Throttle causes the car to buck and sputter. Seems like it is running extremely rich, but the o2's are reading just a little lean (-5 LTFT). Sometimes the when the is popping the LTFT are going rich (up to +4)
I need help. I can't get my tune from Diablo yet on my car until I get a USB to RS232 connector. He sent me a tune to Adjust for the Newer injectors. I had to run open headers for about 15 miles to get back to the house. The o2's are about 1 1/2 from the opening. Would this kill the O2's? Also I think I read somewhere that the Rear O2's from a vette are good to use for the Heatingissue I've read about.
I have o2 sims also.
I also posted this in the external section.
https://ls1tech.com/forums/showthrea...76#post2389876
I need help. I can't get my tune from Diablo yet on my car until I get a USB to RS232 connector. He sent me a tune to Adjust for the Newer injectors. I had to run open headers for about 15 miles to get back to the house. The o2's are about 1 1/2 from the opening. Would this kill the O2's? Also I think I read somewhere that the Rear O2's from a vette are good to use for the Heatingissue I've read about.
I have o2 sims also.
I also posted this in the external section.
https://ls1tech.com/forums/showthrea...76#post2389876
What is your LTFT average?
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From: I play with Sand!!
Not sure yet. I'm going to reset the computer and down load a new tune to delete the rear o2's. I think the sim's a look a little goofy. Not reading like they should.
I put 28.8 lbs injector in over the stock '99 injectors. (26 if I remember right.) The only thing I have changed out since swapping the injectors is the Long Tubes.
JamRWS6 thanks for the heads up's up. I didn't know I had it back wards.
For now I'm going to reset the Computer, install the new tune. Then I drive it areound and see if that helps out any. As far as leaks, I havent noticed any. I'll try blocking off the exhaust and see if I get any.
I put 28.8 lbs injector in over the stock '99 injectors. (26 if I remember right.) The only thing I have changed out since swapping the injectors is the Long Tubes.
JamRWS6 thanks for the heads up's up. I didn't know I had it back wards.
For now I'm going to reset the Computer, install the new tune. Then I drive it areound and see if that helps out any. As far as leaks, I havent noticed any. I'll try blocking off the exhaust and see if I get any.
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From: Dallas, TX
Originally Posted by Richiec77
Not sure yet. I'm going to reset the computer and down load a new tune to delete the rear o2's. I think the sim's a look a little goofy. Not reading like they should.
If you don't have a SES code for the rear O2s then there should be nothing to worry about with the sims.
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if the cat is overtemp, I don't think the PCM would deliver more fuel. I'm not sure about that, but it doens't make sense to me. From what I understand, fuel reacts with the catalyst causing it to heat up and burn off. I could be dead *** wrong, been a brain fart kind of day today.
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Is a backfire caused by too much fuel? I think this is correct. Right now at idle the Ltrims want to stay around -08.25. The O2 voltage is dancing around alot from 55 mv to 900mv. I'm off to get some Vette Rear O2's. When I first started the car it took almost a minute to start registering anything. The exhaust is pretty rich smeeling. It seems right now I'm fighting a rich condition.
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I just threw a P0300 Multiple misfire code. I'm going to change out the plugs and see how it does. And if this doesn't clear the problem I have a set of 13111. Damn $160 for the pair is expensive.
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From: Dallas, TX
Originally Posted by Richiec77
That might be true but if the O2 sims are acting wrong they could send the computer a "Cat Overtemp" signal floading the motor with fuel.
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I got it firured out. Car is running good now. It broke the coolant emperture sensor, and had 2 completely fouled out plugs. New temp sensor and plugs and the car is running great now. Thanks everyone for helping out. That is why I love this site.
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From: Dallas, TX
Originally Posted by Richiec77
I got it firured out. Car is running good now. It broke the coolant emperture sensor, and had 2 completely fouled out plugs. New temp sensor and plugs and the car is running great now. Thanks everyone for helping out. That is why I love this site.
Good to see you got it figured out.