2000 4 cyl hesitating
#11
08-09-2009, 12:04 AM
I was bored today so I decided to check the plugs and pcv to see if they needed to be changed.
I couldn't actually find the pcv, or any vaccuume lines coming off the valve covers. When I looked up the part online, I couldn't even find a pcv valve for this engine. Does it actually have one?
When I pulled the plugs, they were obviously in need of replacment.....30k miles ago. So I ran out and bought a set of bosch double platnums and it seemed to fix the problem. It did bog once while starting from a stop, but the learned fuel trims are probably still messed up from the old plugs.
So here's another Q. When I pulled the bolts holding the cover down to get to the plugs, they had a good coating of oil on them. I had the cover on and off a few times, and it seemed they would recoat with oil after driving (but the inside of the cover was completely dry). The exhaust valve cover has an oil film on it towards the drivers side and there is evidence of a leak in the valley (for lack of better word) down by the driver side. The driver side bolt entering the exhaust side (firewall side) of the head had the most oil on it. There is a sensor that screws into the intake side of the head (I'm assuming cam sensor?) that may be the source of the leak.
Any idea what might me leaking?
I couldn't actually find the pcv, or any vaccuume lines coming off the valve covers. When I looked up the part online, I couldn't even find a pcv valve for this engine. Does it actually have one?
When I pulled the plugs, they were obviously in need of replacment.....30k miles ago. So I ran out and bought a set of bosch double platnums and it seemed to fix the problem. It did bog once while starting from a stop, but the learned fuel trims are probably still messed up from the old plugs.
So here's another Q. When I pulled the bolts holding the cover down to get to the plugs, they had a good coating of oil on them. I had the cover on and off a few times, and it seemed they would recoat with oil after driving (but the inside of the cover was completely dry). The exhaust valve cover has an oil film on it towards the drivers side and there is evidence of a leak in the valley (for lack of better word) down by the driver side. The driver side bolt entering the exhaust side (firewall side) of the head had the most oil on it. There is a sensor that screws into the intake side of the head (I'm assuming cam sensor?) that may be the source of the leak.
Any idea what might me leaking?
#12
08-09-2009, 09:22 AM
well I thought I had it figured out.
I think the bad plugs were just exaggerating the main problem. The worst bogging is now gone, but I'm still having funny issues from time to time.
1. Starting from a stop, it still wants to stumble from time to time.
2. Once I get up to speed, I can feather back the throttle to a point just above idle (seems to be consistently around 1500 rpm), where the RPMs start to randomly flutter. I can't tell if the tranny is gear hunting (or maybe the TC switching in and out of lockup) or if its the engine. It doesn't appear to be missing.
3. When I come to a stop after driving for a while as idle settles down to the 500 rpm range, occasionaly I'll start picking up a miss fire.
4. It still dies on me. I was coasting down a hill and applying light brake, so the engine was idling. When I started applying throttle at the bottom, I initially had zero response, followed by the rpms shooting up to around 3k and it 'catching'...similar feeling to downshifting to pass on the highway. I let up on the throttle again and as the rpms fell back towards idle, they hit 500 rpm, hesitated for a second, then continued to drop until the engine died.
I think the bad plugs were just exaggerating the main problem. The worst bogging is now gone, but I'm still having funny issues from time to time.
1. Starting from a stop, it still wants to stumble from time to time.
2. Once I get up to speed, I can feather back the throttle to a point just above idle (seems to be consistently around 1500 rpm), where the RPMs start to randomly flutter. I can't tell if the tranny is gear hunting (or maybe the TC switching in and out of lockup) or if its the engine. It doesn't appear to be missing.
3. When I come to a stop after driving for a while as idle settles down to the 500 rpm range, occasionaly I'll start picking up a miss fire.
4. It still dies on me. I was coasting down a hill and applying light brake, so the engine was idling. When I started applying throttle at the bottom, I initially had zero response, followed by the rpms shooting up to around 3k and it 'catching'...similar feeling to downshifting to pass on the highway. I let up on the throttle again and as the rpms fell back towards idle, they hit 500 rpm, hesitated for a second, then continued to drop until the engine died.
#14
08-09-2009, 07:36 PM
Yes, but I have a bad wheel bearing which is making the dash light up like a christmas tree. I'm trying to have them read, but I live in podunk MI and am having problems finding a place to do it for free
#15
09-27-2009, 10:21 AM
So over the past few weeks the car has gotten worse.
Now when I'm sitting still with it in drive, the car surges back and forth. If I'm coasting down, sometimes the engine will settle into idle around 1000 rpm, and other times it will just keep falling until it stalls and dies. When I give it gas to keep it from dieing, I have to stab it...I can't just feather the throttle a little. It seems that I have to push the throttle almost to the trans kick down point to get it to respond. The other thing is that if I do feather the throttle and try to hold it just above 1000 rpm, the engine will oscillate between 800 and 1200 rpm in a very steady manner.
Could the bosch plugs be causing some of this (the hesitation at least)? I find it odd that new plugs made such a big difference in drivability and since then the performance has started going down hill again.
Now when I'm sitting still with it in drive, the car surges back and forth. If I'm coasting down, sometimes the engine will settle into idle around 1000 rpm, and other times it will just keep falling until it stalls and dies. When I give it gas to keep it from dieing, I have to stab it...I can't just feather the throttle a little. It seems that I have to push the throttle almost to the trans kick down point to get it to respond. The other thing is that if I do feather the throttle and try to hold it just above 1000 rpm, the engine will oscillate between 800 and 1200 rpm in a very steady manner.
Could the bosch plugs be causing some of this (the hesitation at least)? I find it odd that new plugs made such a big difference in drivability and since then the performance has started going down hill again.
#17
10-08-2009, 01:57 PM
i have a 2000 alero and it has the same problem. i got the codes read and it turns out to be the camshaft position sensor
#20
10-20-2009, 09:38 PM
My 2001 4 cylinder has been giving me the same exact problems (hesitation at take off, dropping to almost non existant RPM when coasting then randomly flying up to 3k all with no "Service Engine Soon" light... well today it got to the point it would hardly stay running without being above 3k RPM and my "Service Engine Soon" light finally came on so I went to the local part store and had it scanned. I got "P0172" "System Too Rich" because of its inconsistency I had a feeling it could be vacuum related... I limped her home and started thoroughly checking my Vacuum lines, starting at the throttle body with the car running (wiggling and pulling the ends of each line) The 3rd line I got to about 4 inches long running from the front of the intake manifold to some random sensor directly under a part of the air intake (something like a secondary airbox with no filter with 2 bolts and 2 hose clamps holding it in place) as soon as I touched it my throttle started bouncing around and stalled upon further prodding. I removed the dry rot hose and replaced it and... Voila its like someone bought me a new car and swapped my keys without telling me.
Check yours out let me know what you find.
Check yours out let me know what you find.
Last edited by speedracer1768; 10-21-2009 at 08:04 PM.