LS1 experts, C3 guy needs help
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
LS1 experts, C3 guy needs help
Hello everybody,
I have a '77 (i bought new) that I put a 2004 LS1 motor and 6 speed trans in.
It runs fine up to about 3300 RPM and then it sputters, it shows codes 171 & 174 showing right and left bank lean. It also showed a MAF code (i forget the number.)
I'm running a Walbro in the back of the car, C5 Corvette regulator and then through the stock line to the front, braided line to the rail. Like I said, really strong until 3300, no popping or backfires, more like sputtering and with the lean codes it has to be running out of fuel.
I have a solid 60 pounds fuel pressure. I'm only running the 2 -O2 sensors on the stock manifolds and the ECM has been modified for this.
Any ideas would be appreciated,
Thanks,
Frank
P.S. here is my car at the Bonneville Salt Flats, scroll down, it's the black one on the trailer; http://www.saltflats.com/2009_photos_1.htm
before the salt attack. Went 125 when I had the problem. Didn't have time to test it before I left, got it running on thursday, left monday.
I have a '77 (i bought new) that I put a 2004 LS1 motor and 6 speed trans in.
It runs fine up to about 3300 RPM and then it sputters, it shows codes 171 & 174 showing right and left bank lean. It also showed a MAF code (i forget the number.)
I'm running a Walbro in the back of the car, C5 Corvette regulator and then through the stock line to the front, braided line to the rail. Like I said, really strong until 3300, no popping or backfires, more like sputtering and with the lean codes it has to be running out of fuel.
I have a solid 60 pounds fuel pressure. I'm only running the 2 -O2 sensors on the stock manifolds and the ECM has been modified for this.
Any ideas would be appreciated,
Thanks,
Frank
P.S. here is my car at the Bonneville Salt Flats, scroll down, it's the black one on the trailer; http://www.saltflats.com/2009_photos_1.htm
before the salt attack. Went 125 when I had the problem. Didn't have time to test it before I left, got it running on thursday, left monday.
Last edited by myoriginal77; Oct 4, 2009 at 11:22 PM. Reason: typo
Tech Contributor
Joined: Jan 2007
Posts: 19,461
Likes: 1,166
From: Dyer, IN
Hello everybody,
I have a '77 (i bought new) that I put a 2004 LS1 motor and 6 speed trans in.
It runs fine up to about 3300 RPM and then it sputters, it shows codes 171 & 174 showing right and left bank lean. It also showed a MAF code (i forget the number.)
I'm running a Walbro in the back of the car, C5 Corvette regulator and then through the stock line to the front, braided line to the rail. Like I said, really strong until 3300, no popping or backfires, more like sputtering and with the lean codes it has to be running out of fuel.
I have a solid 60 pounds fuel pressure. I'm only running the 2 -O2 sensors on the stock manifolds and the ECM has been modified for this.
Any ideas would be appreciated,
Thanks,
Frank
P.S. here is my car at the Bonneville Salt Flats, scroll down, it's the black one on the trailer; http://www.saltflats.com/2009_photos_1.htm
before the salt attack. Went 125 when I had the problem. Didn't have time to test it before I left, got it running on thursday, left monday.
I have a '77 (i bought new) that I put a 2004 LS1 motor and 6 speed trans in.
It runs fine up to about 3300 RPM and then it sputters, it shows codes 171 & 174 showing right and left bank lean. It also showed a MAF code (i forget the number.)
I'm running a Walbro in the back of the car, C5 Corvette regulator and then through the stock line to the front, braided line to the rail. Like I said, really strong until 3300, no popping or backfires, more like sputtering and with the lean codes it has to be running out of fuel.
I have a solid 60 pounds fuel pressure. I'm only running the 2 -O2 sensors on the stock manifolds and the ECM has been modified for this.
Any ideas would be appreciated,
Thanks,
Frank
P.S. here is my car at the Bonneville Salt Flats, scroll down, it's the black one on the trailer; http://www.saltflats.com/2009_photos_1.htm
before the salt attack. Went 125 when I had the problem. Didn't have time to test it before I left, got it running on thursday, left monday.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
Hello,
I don't have the MAF code handy (i'm at work, it's at home) but the MAF is clean and I did have an air filter on it, so no salt.
Also, on the advice of a freind, I dis-connected the battery and unpluggged the MAF, re-connected the battery and started it which should put it in by-pass speed density mode eliminating the MAF and it still did the same thing.
I originally figured it was going to be a bad fuel pump (i didn't have the guage with me in Utah-DUH) but the guage is a solid 60.
Thanks, I will post the MAF code tomorrow,
Frank
I don't have the MAF code handy (i'm at work, it's at home) but the MAF is clean and I did have an air filter on it, so no salt.
Also, on the advice of a freind, I dis-connected the battery and unpluggged the MAF, re-connected the battery and started it which should put it in by-pass speed density mode eliminating the MAF and it still did the same thing.
I originally figured it was going to be a bad fuel pump (i didn't have the guage with me in Utah-DUH) but the guage is a solid 60.
Thanks, I will post the MAF code tomorrow,
Frank
Tech Contributor
Joined: Jan 2007
Posts: 19,461
Likes: 1,166
From: Dyer, IN
Hello,
I don't have the MAF code handy (i'm at work, it's at home) but the MAF is clean and I did have an air filter on it, so no salt.
Also, on the advice of a freind, I dis-connected the battery and unpluggged the MAF, re-connected the battery and started it which should put it in by-pass speed density mode eliminating the MAF and it still did the same thing.
I originally figured it was going to be a bad fuel pump (i didn't have the guage with me in Utah-DUH) but the guage is a solid 60.
Thanks, I will post the MAF code tomorrow,
Frank
I don't have the MAF code handy (i'm at work, it's at home) but the MAF is clean and I did have an air filter on it, so no salt.
Also, on the advice of a freind, I dis-connected the battery and unpluggged the MAF, re-connected the battery and started it which should put it in by-pass speed density mode eliminating the MAF and it still did the same thing.
I originally figured it was going to be a bad fuel pump (i didn't have the guage with me in Utah-DUH) but the guage is a solid 60.
Thanks, I will post the MAF code tomorrow,
Frank
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
Hello, thanks again,
The motor I put in was from a car I parted out, it only had 625 miles on it so the motor is basically new, harness came with it although I sent it out to be modified. Everything else is stock other then some things to get it into the '77.
I did get to run it in the donor car before I pulled it but only standing still and not to 3300 rpm but it seemed to run fine. As it does now, very strong to that point.
Frank
The motor I put in was from a car I parted out, it only had 625 miles on it so the motor is basically new, harness came with it although I sent it out to be modified. Everything else is stock other then some things to get it into the '77.
I did get to run it in the donor car before I pulled it but only standing still and not to 3300 rpm but it seemed to run fine. As it does now, very strong to that point.
Frank
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Frank
The air ducting between the throttle Boy and the MAF needs to be 100% air tight. If there is ANY un-metered air entering the engine, the engine can go lean.
Things to consider:
- Master brake vacuum leakage-
- PCV air leakage
Check that out.
BC
The air ducting between the throttle Boy and the MAF needs to be 100% air tight. If there is ANY un-metered air entering the engine, the engine can go lean.
Things to consider:
- Master brake vacuum leakage-
- PCV air leakage
Check that out.
BC
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
Bill, Thanks for the ideas,
I'm pretty sure about the air path in and the brake booster, I will check the PVC.
The other thing you made me think about is on the drivers side intake there is a solenoid for the vapor canister, a purge valve I think. I still have it going into the throttle body and have the other end crimped. I'm wondering if that might be an issue.
The one other thing I thought about was why it does it at 3300 and not sooner, maybe some fuction is keyed to that RPM.
Frank
I'm pretty sure about the air path in and the brake booster, I will check the PVC.
The other thing you made me think about is on the drivers side intake there is a solenoid for the vapor canister, a purge valve I think. I still have it going into the throttle body and have the other end crimped. I'm wondering if that might be an issue.
The one other thing I thought about was why it does it at 3300 and not sooner, maybe some fuction is keyed to that RPM.
Frank
Last edited by myoriginal77; Oct 5, 2009 at 01:58 AM. Reason: typo
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Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
The saga continues ...
In checking my motor, I do not (that i could find) have a PCV valve at all. In the front of the motor on the throttle body is a short piece of hose that connects to a nipple on the intake right below it.
In pictures I've seen it looks like there should be a PCV valve in a rubber line that runs from that throttle body nipple to the back of the motor. On the back of my motor there is a nipple on the top of the drivers side head that has a rubber plug on it. It looks factory but I have no idea, maybe it supposed to be like that.
Other than that, I double checked and the booster and line look OK, it holds vacuum, vacuum lines and all the connections at the MAF are tight.
I'm still wondering about that vapor solenoid although I did have the end sealed off.
I'm stumped,
Thanks,
Frank
In pictures I've seen it looks like there should be a PCV valve in a rubber line that runs from that throttle body nipple to the back of the motor. On the back of my motor there is a nipple on the top of the drivers side head that has a rubber plug on it. It looks factory but I have no idea, maybe it supposed to be like that.
Other than that, I double checked and the booster and line look OK, it holds vacuum, vacuum lines and all the connections at the MAF are tight.
I'm still wondering about that vapor solenoid although I did have the end sealed off.
I'm stumped,
Thanks,
Frank
Last edited by myoriginal77; Oct 8, 2009 at 12:05 AM. Reason: typo
Tech Contributor
Joined: Jan 2007
Posts: 19,461
Likes: 1,166
From: Dyer, IN
In checking my motor, I do not (that i could find) have a PCV valve at all. In the front of the motor on the throttle body is a short piece of hose that connects to a nipple on the intake right below it.
In pictures I've seen it looks like there should be a PCV valve in a rubber line that runs from that throttle body nipple to the back of the motor. On the back of my motor there is a nipple on the top of the drivers side head that has a rubber plug on it. It looks factory but I have no idea, maybe it supposed to be like that.
Other than that, I double checked and all my exhaust stuff looks good.
I'm stumped,
Thanks,
Frank
In pictures I've seen it looks like there should be a PCV valve in a rubber line that runs from that throttle body nipple to the back of the motor. On the back of my motor there is a nipple on the top of the drivers side head that has a rubber plug on it. It looks factory but I have no idea, maybe it supposed to be like that.
Other than that, I double checked and all my exhaust stuff looks good.
I'm stumped,
Thanks,
Frank
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
right now i'm blocked (at work) posting pic, maybe this flickr link will work for my work around, sorry they are cell phone pics.
http://www.flickr.com/photos/43344100@N05/3994220539/
In the first picture you cabn see the loop of hose from the manifold to the throttle body.
Second is the rubber nipple on the driver's side rear and then the 3rd is with the nipple removed.
This motor was virtually new when I got it (625 miles) and I can only assume that it was like this. I've searched for pictures and all look like there should be a PCV valve in that hose loop.
Thanks,
Frank
http://www.flickr.com/photos/43344100@N05/3994220539/
In the first picture you cabn see the loop of hose from the manifold to the throttle body.
Second is the rubber nipple on the driver's side rear and then the 3rd is with the nipple removed.
This motor was virtually new when I got it (625 miles) and I can only assume that it was like this. I've searched for pictures and all look like there should be a PCV valve in that hose loop.
Thanks,
Frank
Last edited by myoriginal77; Oct 9, 2009 at 03:08 AM. Reason: typo
Burning Brakes
Joined: Oct 2008
Posts: 898
Likes: 25
From: Dallas, TX
I searched around when I replaced my PCV and found a bunch of folks had trouble finding it. Mine is an 03 and if I pull the small hose off the TB the other end of the small hose is connected to the PCV, which is actually stuffed into the larger hose right next to it. It's not inserted into the valve cover like on most cars.
Good luck!
Good luck!
Last edited by 03WhiteConv; Oct 9, 2009 at 09:33 AM.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
I searched around when I replaced my PCV and found a bunch of folks had trouble finding it. Mine is an 03 and if I pull the small hose off the TB the other end of the small hose is connected to the PCV, which is actually stuffed into the larger hose right next to it. It's not inserted into the valve cover like on most cars.
Good luck!
Good luck!
Frank
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,450
Likes: 40
From: Panama City Beach, Florida
Take a look at this link, my motor is exactly like the motor they show without the intake (scroll down) so then mine is more like a LS2 system, no PCV, wierd ... says LS1 on the front
http://ls1tech.com/forums/generation...cv-system.html
So if the PCV is not the issue I still have to figure out what's wrong ???
thanks,
Frank
http://ls1tech.com/forums/generation...cv-system.html
So if the PCV is not the issue I still have to figure out what's wrong ???
thanks,
Frank