1994 Chevy 5.7 Idle Issues
October 1st, 2014 | 8:12 PM
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1994 Chevy 5.7 Idle Issues
I would like to start out by saying this is my first post on this forum and I'm excited for the world of knowledge and experience I'm entering on this forum. I'm not new to the forum life though, as I was previously very active on the Jeep Forum haha. Now, onto one of my MANY issues.....
As the thread title states I'm having some pretty bad idle issues. I've read a few forums on this general topic but I couldnt really come to a definitive conclusion on my isse, so here we are. My truck is a "1994 GMC C1500" However, thats not at all what it is.... Lol. For one its got a solid corporate 10 bolt front axle, a TH350 transmission, pretty sure its a 205 transfer case and 40" super swampers.
However the problem im discussing in this thread has to do with the 5.7 350 TBI Engine which is out of what I was told a late 80s model Suburban. It idles VERY low (The tach reads roughly 300 RPM's at idle) and you can hear it cut out and skip every few seconds at an irregular rate, so its not predictable. I was told that it has some sort of aftermarket Cam in it as well. It also runs VERY rich. I've replaced the plugs, wires, MAP sensor and CTS with no changes. I thought the catalytic converters were plugged up (which they definitely were) so I had them cut off and new pipes run that dump under the bed with no mufflers.... for now.
I'm absolutely stumped on this one. Forgive me if I havent given enough information, I'll be more than happy to give more information, just not sure how many of the symptoms my truck has are relative haha.
As the thread title states I'm having some pretty bad idle issues. I've read a few forums on this general topic but I couldnt really come to a definitive conclusion on my isse, so here we are. My truck is a "1994 GMC C1500" However, thats not at all what it is.... Lol. For one its got a solid corporate 10 bolt front axle, a TH350 transmission, pretty sure its a 205 transfer case and 40" super swampers.
However the problem im discussing in this thread has to do with the 5.7 350 TBI Engine which is out of what I was told a late 80s model Suburban. It idles VERY low (The tach reads roughly 300 RPM's at idle) and you can hear it cut out and skip every few seconds at an irregular rate, so its not predictable. I was told that it has some sort of aftermarket Cam in it as well. It also runs VERY rich. I've replaced the plugs, wires, MAP sensor and CTS with no changes. I thought the catalytic converters were plugged up (which they definitely were) so I had them cut off and new pipes run that dump under the bed with no mufflers.... for now.
I'm absolutely stumped on this one. Forgive me if I havent given enough information, I'll be more than happy to give more information, just not sure how many of the symptoms my truck has are relative haha.
December 4th, 2022 | 9:15 PM
#2
CF Beginner
Joined: Dec 2022
Posts: 3
Likes: 0
I would like to start out by saying this is my first post on this forum and I'm excited for the world of knowledge and experience I'm entering on this forum. I'm not new to the forum life though, as I was previously very active on the Jeep Forum haha. Now, onto one of my MANY issues.....
As the thread title states I'm having some pretty bad idle issues. I've read a few forums on this general topic but I couldnt really come to a definitive conclusion on my isse, so here we are. My truck is a "1994 GMC C1500" However, thats not at all what it is.... Lol. For one its got a solid corporate 10 bolt front axle, a TH350 transmission, pretty sure its a 205 transfer case and 40" super swampers.
However the problem im discussing in this thread has to do with the 5.7 350 TBI Engine which is out of what I was told a late 80s model Suburban. It idles VERY low (The tach reads roughly 300 RPM's at idle) and you can hear it cut out and skip every few seconds at an irregular rate, so its not predictable. I was told that it has some sort of aftermarket Cam in it as well. It also runs VERY rich. I've replaced the plugs, wires, MAP sensor and CTS with no changes. I thought the catalytic converters were plugged up (which they definitely were) so I had them cut off and new pipes run that dump under the bed with no mufflers.... for now.
I'm absolutely stumped on this one. Forgive me if I havent given enough information, I'll be more than happy to give more information, just not sure how many of the symptoms my truck has are relative haha.
As the thread title states I'm having some pretty bad idle issues. I've read a few forums on this general topic but I couldnt really come to a definitive conclusion on my isse, so here we are. My truck is a "1994 GMC C1500" However, thats not at all what it is.... Lol. For one its got a solid corporate 10 bolt front axle, a TH350 transmission, pretty sure its a 205 transfer case and 40" super swampers.
However the problem im discussing in this thread has to do with the 5.7 350 TBI Engine which is out of what I was told a late 80s model Suburban. It idles VERY low (The tach reads roughly 300 RPM's at idle) and you can hear it cut out and skip every few seconds at an irregular rate, so its not predictable. I was told that it has some sort of aftermarket Cam in it as well. It also runs VERY rich. I've replaced the plugs, wires, MAP sensor and CTS with no changes. I thought the catalytic converters were plugged up (which they definitely were) so I had them cut off and new pipes run that dump under the bed with no mufflers.... for now.
I'm absolutely stumped on this one. Forgive me if I havent given enough information, I'll be more than happy to give more information, just not sure how many of the symptoms my truck has are relative haha.
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