just outta curiousity, check your plugs. make sure one isnt cracked and check the gap. hell, while your at it just replace them.
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
As stated, I replaced them, and they are fine. I made a nice list of everything I changed or checked in the most recent summary post.
Some guy I talked to thinks I might need to adjust the minimum idle airflow screw.
Dunno.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
[ion wrote: C2]As stated, I replaced them, and they are fine. I made a nice list of everything I changed or checked in the most recent summary post.
Some guy I talked to thinks I might need to adjust the minimum idle airflow screw.
Dunno.
My experience (on the J's) is you do not mess with that.
FU Tuning
unless you raise the idle like i did
you want the IAC position to be between 9-15, mine's around 20 at idle since i set it electronically higher than it is stock
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
Hey ion why didn't you use the gasket that came with the header? Besides having no egr i mean. Take the header off and and use the gasket that came with it and weld the hole shut for the egr tube. My experience with headers on anything with metal gaskets(copper) and such it they won't seal when the header would get hot. It was like the flange would warp. With a cast manfiold being basically more rigid the metal gaskets work fine for some reason.
I'm running a 2000 2.4 in my 99 fire and gave fits like yours. Use the greyish gasket that came with it not the metal 2000 gasket. With the metal gasket mine would leak. Also use a heated o2. That wa another problem. And with your vibes your saying you have. You have to remeber the stock down pipe had a flex joint in it. Your exhuast now ist more solider and less prone to moving which will vibrate the whole exhuast all the way back.
On another note the down pipe will leak where it connects. I don't care what you do it might not be yet but it will start. Also move your o2 sensor up close to where the cavalier hole is if not a little higher. I don't think you quite understand how that will affect your a/f mixture readings. Have you ever seen a car dynoed with a wideband in the tail pipe and in the header or manifold? I have seen readings be almost 3 points lean at the tail pipe compared to readins in the header.
Kind of like taking your stock o2 sensor put it in the tail pipe. It is going to stumble and carring on because it would be moreless flooding even though on a datalog it will say the a/f is fine. You also wouldn't throw codes. Keep the o2 sensor in the collector though but move it as far up as possible to where the pipes join. Where you got your o2 now compared to moving it up there i would figure there would be anywhere from .1 to .4 difference. Mainly saying that where it is now would be leaner than up futher.
One big problem with you having it down there is if that flex joint is leaking the slightest it will throw off you a/f mixture worse than being in the header.
[ion wrote: C2]unless you raise the idle like i did
you want the IAC position to be between 9-15, mine's around 20 at idle since i set it electronically higher than it is stock
In the past when we tried raising the idle by the screw the IAC corrected what we did. This is why I recommend not messing with it. Want to raise the idle use HPT to do so.
I have seen, or heard , or read of more people having problems with manifold gaskets that are not metal. I have never had a leak with my orginally stock 2001 metal gasket. Even when I installed the header kept the orginal gasket no leaks. No leaks at the downpipe either.
FU Tuning
John Higgins wrote:In the past when we tried raising the idle by the screw the IAC corrected what we did. This is why I recommend not messing with it. Want to raise the idle use HPT to do so.
Yep, I put a shim between the throttle stop today to test my theory, the IAC corrected it, lol, no change in idle.
John Higgins wrote:I have seen, or heard , or read of more people having problems with manifold gaskets that are not metal. I have never had a leak with my orginally stock 2001 metal gasket. Even when I installed the header kept the orginal gasket no leaks. No leaks at the downpipe either
It's metal. I do not have any exhaust leaks.
Blown Phoniex wrote:Hey ion why didn't you use the gasket that came with the header? Besides having no egr i mean. Take the header off and and use the gasket that came with it and weld the hole shut for the egr tube. My experience with headers on anything with metal gaskets(copper) and such it they won't seal when the header would get hot. It was like the flange would warp. With a cast manfiold being basically more rigid the metal gaskets work fine for some reason.
There was no "gasket that came with the header," I bought it off WrenchMonkey on here. I bought a 2000+ non-EGR gasket as I should. It is not copper. I could cut off and weld the EGR tube shut, but there have been examples of people on here using my exact same setup with no issues. I wouldn't think a little tube on the side of the 4th runner would cause problems, and ONLY at idle.
Blown Phoniex wrote:I'm running a 2000 2.4 in my 99 fire and gave fits like yours. Use the greyish gasket that came with it not the metal 2000 gasket. With the metal gasket mine would leak. Also use a heated o2. That wa another problem. And with your vibes your saying you have. You have to remeber the stock down pipe had a flex joint in it. Your exhuast now ist more solider and less prone to moving which will vibrate the whole exhuast all the way back.
I do not have a leak. Multiple shops with 20+ years of experience confirmed this, I checked nut torque, felt around, NO leaks. The vibes are NOT simply "just how it is with a header" I have a HUGE flex pipe after the downpipe. The stock flexpipe is like 3", this one is over a foot long. If it was simply engine shaking then why does the exhaust sound like it's misfiring? Why does my wideband spike to lean and it runs rough sitting at idle.
At ANY amount of throttle, it's SO smooth, but when I let off it's back to the sputtering putt idle. I
do have a heated O2, I hit closed loop within 15 seconds of cold start.
Blown Phoniex wrote:On another note the down pipe will leak where it connects. I don't care what you do it might not be yet but it will start. Also move your o2 sensor up close to where the cavalier hole is if not a little higher. I don't think you quite understand how that will affect your a/f mixture readings. Have you ever seen a car dynoed with a wideband in the tail pipe and in the header or manifold? I have seen readings be almost 3 points lean at the tail pipe compared to readins in the header.
Kind of like taking your stock o2 sensor put it in the tail pipe. It is going to stumble and carring on because it would be moreless flooding even though on a datalog it will say the a/f is fine. You also wouldn't throw codes. Keep the o2 sensor in the collector though but move it as far up as possible to where the pipes join. Where you got your o2 now compared to moving it up there i would figure there would be anywhere from .1 to .4 difference. Mainly saying that where it is now would be leaner than up futher.
One big problem with you having it down there is if that flex joint is leaking the slightest it will throw off you a/f mixture worse than being in the header
Oh I understand, that was my main point, I had it checked out over and over for leaks at that ball joint since I figured if it leaked there that would throw off the reading. The ball joint connection is very tight. I have a large flexpipe welded to the downpipe to provide as much flex as it needs. The O2 sensor is very close to the header's original location, and it is heated now.
And that whole area of inspection is TOTALLY irrelevant, since
THIS HAPPENS IN OPEN LOOP TOO! I can disconnect the sensor or disable CL in HPTuners and run around in open loop with 12 AFRs and it still sputters at idle! And remember, this is
ONLY AT IDLE. All other aspects of driving are
perfectly fine.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
Ignore all previous data, this is what happens, what I tried, a summary.
This doesn't affect anything but idle.. Seems when it thumps and acts like it misfires, there's a spike to lean real quick.
What causes a rough idle (apparent misfire) but:
- runs fine otherwise as far as I can tell
- displays no codes
- no apparent vacuum leaks
- FPR, IAC, TPS are fine
- header nuts are tight, no exhaust leaks
-
not O2 related! happens in open loop too!
- kitty is nice and clear
- installed new spark plugs/coil pack housing/boots/springs
- ran a wire from the ICM bottom (between the ICM and IDI cover) to an IDI cover bolt to test if I needed the ground strap I removed 15 minutes before header install by swapping engine covers
- pulled fuel rail and reinstalled, ensuring the injectors were seated properly
- fuel pressure at idle is 48 psi
- at even 1% throttle at idle it runs heavenly smooth
header --> downpipe --> flexpipe --> cat --> magnaflow --> piping --> dynomax --> outlets
All we did during the header install was:
1. unbolt stock downpipe
2. cut off pipe after cat just before magnaflow
3. removed strut bar, heat shield, coolant bracket, then stock manifold and gasket
4. installed header, had to remove oil dipstick and move the brake booster hose out of the way
5. tightened nuts, reinstalled dipstick and booster line and bracket
6. realized o2 bung location left zero room, so we plugged it with a threaded plug
7. welded o2 bungs (upstream & wideband) on the downpipe
8. bolted downpipe to header
9. welded flexpipe to downpipe
10. cut cat off of old piping, welded it to flexpipe and magnaflow
11. welded bung after cat for rear o2
12. reinstalled all o2 sensors
Remember, this is simply a Pacesetter header with the EGR tube, installed on a 2000 non-EGR engine using the 2000+ exhaust gasket, metal, fel-pro, not copper.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
John i was mainly just saying that was my experience. I've had real bad luck with the copper header gaskets for my t/a mainly. Some people haven't had a problem using a metal gasket. But i think this is mainly due to the manufacturing variables.
Ion i was showing any disrespect or anything i was just trying to help out. But i also overlooked where you said it was going into open loop in like 10 secs. But o2 sensor location does play a big role in how the motor is going to run. I also thought yo just installed the header and down pipe. With no sort of flex pipe. So i stand corrected on that. I'm not running a flex pipe at all and that is how I'm getting vibes. Nothing that really bugs me though. As for your leak at the joint you got lucky i guess. Because mine is leaking there real bad until it seems to get nice and hot. But i figure you also have solid mounts and that flex pipe probably helps out a good bit. When i installed my down pipe it was tight and no leaks but from it moving back and forth and with stock mounts mainly causing it. It's loose now and with the bolts than came with it there as tight as they will go.
On the side though you said it happens in open loop also. Well my o2 sensor problem was in open loop also mainly due to the fact that the o2 wasn't heating up right away. About 20 to 25 secs. But it would miss and caring on after running for about 5 to 10 sec's.
Yeah... I dunno.
Another Alero owner just fixed his rough idle issue with a loose manifold bolt, should probably check my torque or spray WD40 around it, I don't remember spraying any around there... everywhere else though.
I also just raised my idle spark advance 3 degrees per a suggestion from a friend after going over logs. We'll see what happens when I flash it tomorrow.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
SOLVED!
Intake manifold bolts were loose. LOL
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
Yep, got back from tuning the idle and low RPM VE too. Can't even tell it's on at idle, it's so smooth.
Took me 3 weeks to realize the problem though. I'm a dumbass, I know. I'm so happy though. It's the one area I didn't spray carb cleaner... til today..
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
Did the intake manifold loosen on it's own or did you loosen it at some point?
2003 Sunfire with 2 1/4 inch turbo muffler, 2 1/4 piping, 2 1/2 inch resonator, a 2 1/4 inch catalytic converter, 2 1/2 inch down-pipe, a 4:2:1 RK Sports 'clone' header, E-bay strut brace, ground wire kit and an AEM true cold air intake NOPI edition.
by itself over time, i doubt i torqued it correctly back in the day when i put the supercharger on
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
lol all that work and frustration
