P1404 code 1999 suburban L31
Moderator: Team
P1404 code 1999 suburban L31
Final chapter in this Suburban saga
1999 suburban C2500, stock L31 Vortec 350. Idles “mostly” smooth at idle with just a faint touch of roughness. Runs normal and smooth at medium or heavier throttle, but at very light throttle acceleration or cruise, it bucks, misfires, burbles, etc...and it all clears up as soon as you give it more throttle. I’ve cleaned the EGR valve before...does it sound like it is time to replace it? The P1404 code on this means the egr valve is stuck in the closed position according to my scan tool. Does the drivability symptoms match a stuck closed egr valve?
1999 suburban C2500, stock L31 Vortec 350. Idles “mostly” smooth at idle with just a faint touch of roughness. Runs normal and smooth at medium or heavier throttle, but at very light throttle acceleration or cruise, it bucks, misfires, burbles, etc...and it all clears up as soon as you give it more throttle. I’ve cleaned the EGR valve before...does it sound like it is time to replace it? The P1404 code on this means the egr valve is stuck in the closed position according to my scan tool. Does the drivability symptoms match a stuck closed egr valve?
Re: P1404 code 1999 suburban L31
I had one that would stick and run like crap, I don't know if it was open are closed but you could smack it a cpl times with a hammer and it was good to go for a few months.travis wrote: ↑Fri Jul 17, 2020 9:43 pm Final chapter in this Suburban saga
1999 suburban C2500, stock L31 Vortec 350. Idles “mostly” smooth at idle with just a faint touch of roughness. Runs normal and smooth at medium or heavier throttle, but at very light throttle acceleration or cruise, it bucks, misfires, burbles, etc...and it all clears up as soon as you give it more throttle. I’ve cleaned the EGR valve before...does it sound like it is time to replace it? The P1404 code on this means the egr valve is stuck in the closed position according to my scan tool. Does the drivability symptoms match a stuck closed egr valve?
Please Note!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
THE ABOVE POST IN NO WAY REFLECTS THE VIEWS OF SPEED TALK OR IT'S MEMBERS AND SHOULD BE VIEWED AS ENTERTAINMENT ONLY...Thanks, The Management!
Re: P1404 code 1999 suburban L31
I’ll have to try that. I really don’t want to spend any more money on this thing.
Re: P1404 code 1999 suburban L31
https://www.napaonline.com/en/p/NDP7002600
Clean it again and put one of tbese on it. Screened gasket....helps to keep it from it getting more crap in it.
Clean it again and put one of tbese on it. Screened gasket....helps to keep it from it getting more crap in it.
Re: P1404 code 1999 suburban L31
Do you live close to there? My parents live just outside of AftonCGT wrote: ↑Fri Jul 17, 2020 10:30 pm https://www.napaonline.com/en/p/NDP7002600
Clean it again and put one of tbese on it. Screened gasket....helps to keep it from it getting more crap in it.
Re: P1404 code 1999 suburban L31
Travis,
Did I give you a handful of Chevy lug-bolts the last time you were up here??
If so please send them back to me, I need them to finish my cars suspension is all. All of them...
I will pay you for S&H..
Thanks...
pdq67
Did I give you a handful of Chevy lug-bolts the last time you were up here??
If so please send them back to me, I need them to finish my cars suspension is all. All of them...
I will pay you for S&H..
Thanks...
pdq67
Re: P1404 code 1999 suburban L31
Didn't realize I gave up my location until I reread my link. I believe Afton is south of STL...I'd be about an hour northish from there.travis wrote: ↑Sat Jul 18, 2020 12:02 amDo you live close to there? My parents live just outside of AftonCGT wrote: ↑Fri Jul 17, 2020 10:30 pm https://www.napaonline.com/en/p/NDP7002600
Clean it again and put one of tbese on it. Screened gasket....helps to keep it from it getting more crap in it.
Re: P1404 code 1999 suburban L31
Sorry...it’s a weird character flaw of mineCGT wrote: ↑Sat Jul 18, 2020 8:20 amDidn't realize I gave up my location until I reread my link. I believe Afton is south of STL...I'd be about an hour northish from there.travis wrote: ↑Sat Jul 18, 2020 12:02 amDo you live close to there? My parents live just outside of AftonCGT wrote: ↑Fri Jul 17, 2020 10:30 pm https://www.napaonline.com/en/p/NDP7002600
Clean it again and put one of tbese on it. Screened gasket....helps to keep it from it getting more crap in it.
-
- HotPass
- Posts: 1862
- Joined: Sun Mar 01, 2009 2:42 am
- Location: The Seasonally Frozen Wastelands
Re: P1404 code 1999 suburban L31
I don't know why a closed EGR valve would cause those problems.travis wrote: ↑Fri Jul 17, 2020 9:43 pmat very light throttle acceleration or cruise, it bucks, misfires, burbles, etc...and it all clears up as soon as you give it more throttle... ...The P1404 code on this means the egr valve is stuck in the closed position according to my scan tool. Does the drivability symptoms match a stuck closed egr valve?
Stuck OPEN might.
Re: P1404 code 1999 suburban L31
Well...that wasn’t it. The old one wasn’t stuck, and the good used one I just replaced it with made no difference at all.
This thing is acting just like it did when the TPS went bad. The TPS was replaced maybe a year ago. I have rechecked it and see 0.65v at idle, 4.69v at WOT, and a smooth linear voltage increase from idle on up.
This engine is tired, which isn’t helping the troubleshooting at all.
This thing is acting just like it did when the TPS went bad. The TPS was replaced maybe a year ago. I have rechecked it and see 0.65v at idle, 4.69v at WOT, and a smooth linear voltage increase from idle on up.
This engine is tired, which isn’t helping the troubleshooting at all.
Re: P1404 code 1999 suburban L31
Are you sure that the passages in the intake manifold aren't plugged up?
Re: P1404 code 1999 suburban L31
I cleaned everything out when I replaced the intake gaskets and spider injector assembly last year. It “shouldn’t” be clogged.
Re: P1404 code 1999 suburban L31
Do you have access to a full feature scan tool? If so, command the egr valve to 100% and see if it dies. If it doesn't, the passage is plugged somewhere.