Thought I should put this in the performance forum as I have some upgrades. 2001 base model cavalier 2200. Intake, header, upgraded upstream oxygen sensor with 4 wire heated sensor, new plugs and wires, new fuel filter, engine has about 50K on it. At 75% to 100% throttle, mostly in second gear, the car seems to bobble. It doesn't accelerate smoothly. When I'm not really on the throttle, it doesn't seem to do it. It kind of feels like it has just a little bit too much fuel. I know these engines tend to run rich. Also, it's done this before the oxygen sensor upgrade, and before the new plugs, wires, and fuel filter. Maybe I need some coil packs/module? Ideas would be great; thanks for the help in advance guys.
"In Oldskool we trust"
Are your plugs black or burnt looking? Dont upgrade anything, fix what the problem is rather then adding to it with more upgrades. What kind of plug wires did you get? Have you tried putting your old ones back on. I have a hard time believing your running to rich unless you left off something like a fuel pump, bigger injectors or a fuel pressure regulator that you recently added.
Just to be clear, this does happen at 100% throttle? Not just the section leading up to it, but actually pedal to the metal?
Also, as said, you need to see what your plugs look like.
fortune cookie say: better a delay than a disaster
maybe you jus have a broken belt in your tire..Same thing happens to me..Because of this
Thanks for the input guys. Yes, it does happen at wide open throttle as well. It does NOT happen at cold start up and run. It only happens once it warms up and goes into closed loop. Plugs are chocolate brown like they should be, maybe a little on the lean side actually. Wires were the napa specials, nothing spectacular but I know they work. I have a lot of leftover brand new plug wires from napa because every other time we get them at my shop they throw in an extra by accident. I tried replacing all 4 with those odds and ends that had the right boot style but no luck. As for the tire issue, I suppose it's possible, but the bobble really isnt that uniform. It only really does it in second gear and rarely 3rd. You can actually feel the engine rocking back and forth in the cradle a little. Maybe it's actually starving since the plugs look whiter than they maybe should be. Fuel filter's fairly new, but i ran it low on gas after that so maybe i clogged it. Possibly a clogged injector as well i suppose. It's done this for a very long time, maybe even pre-header.
"In Oldskool we trust"
Ryan Pitt wrote:Thanks for the input guys. Yes, it does happen at wide open throttle as well. It does NOT happen at cold start up and run. It only happens once it warms up and goes into closed loop.
This is why I asked about WOT, as WOT is open-loop as well. So, if it's occuring at WOT, I think we can rule out the O2 sensor.
Ryan Pitt wrote:Plugs are chocolate brown like they should be, maybe a little on the lean side actually. Wires were the napa specials, nothing spectacular but I know they work. I have a lot of leftover brand new plug wires from napa because every other time we get them at my shop they throw in an extra by accident. I tried replacing all 4 with those odds and ends that had the right boot style but no luck. As for the tire issue, I suppose it's possible, but the bobble really isnt that uniform. It only really does it in second gear and rarely 3rd. You can actually feel the engine rocking back and forth in the cradle a little. Maybe it's actually starving since the plugs look whiter than they maybe should be. Fuel filter's fairly new, but i ran it low on gas after that so maybe i clogged it. Possibly a clogged injector as well i suppose. It's done this for a very long time, maybe even pre-header.
I think you're okay with fuel. Have you had the coil packs and ignition module tested?
fortune cookie say: better a delay than a disaster
OHV notec wrote:This is why I asked about WOT, as WOT is open-loop as well. So, if it's occuring at WOT, I think we can rule out the O2 sensor.
Why do I not think about this stuff?
I'm also leaning towards the module and/or coil packs. How do I go about getting them tested? I don't think I have that equipment at my shop. What I can tell you is that I have a box full of used GM coil packs and had no luck when I interchanged them a few times; although they
were all used...
"In Oldskool we trust"
Ryan Pitt wrote:I'm also leaning towards the module and/or coil packs. How do I go about getting them tested? I don't think I have that equipment at my shop. What I can tell you is that I have a box full of used GM coil packs and had no luck when I interchanged them a few times; although they were all used...
You can take the module to Checker/Schucks/Kragen/whatever and they can test it.
fortune cookie say: better a delay than a disaster
What are the odds of it being a crank-sensor? My '94 truck's running a l'il rough right now & I don't wanna drop dough on parts just to do a trail-&-error check. Did I meant it misses too? And I replaced the coils with new ones?
Go beyond the "bolt-on".
The module and coils came back ok. I have an extra crank sensor from the first engine I blew, maybe I'll give that a shot and see what happens. I'm not holding my breath though.
"In Oldskool we trust"
My car is doing the same type of thing, I'm still trying to figure out its issue. 86K, fuel filter 3 oil changes ago, plugs at 73K, premium wires at 80K or so. mine "bobbles, jerks, or bucks" at constant speed on the highway and my rpms will go from a steady 2500 to 3000 without me moving the pedal..and jerks.
I have to check my plugs to make sure they are ok, other than that, I have no clue. No check engine lights...about a month ago I had an O2 check engine go off(not sure what code) but Autozone said it was an O2, but then it went away...
Interesting that this is a common problem. Mine doesn't do it as bad as verocity's. just enough to pi$$ me off.
"In Oldskool we trust"
I had a pretty bad issue with mine. I would be driving and the car would turn off all by itself. Mine was an electrical issue. Good luck man and keep us posted.
I noticed today (paying real close attention) that im idling a little rough. I'm going to check my plugs and wires tomorrow. I've got NGK Tr6's for the nitrous kit I purchased, and those might be going in sooner than expected..
I also have BOSCH - Lifetime warranty wires...are those crap maybe? I have each wire wrapped in wire loom because I had a problem in the past with the wires rubbing and then arching against metal.
Given the service history of the '94, I wouldn't be surprised if maybe an injector's plugged, and they need replacement. They're still costly thou, and to replace them before finding it's actually something ignition-related would suck. Oh yeah, it also misses while cruising under part-throttle uphill.
Go beyond the "bolt-on".
Seems like my issue is minor when compared with all this. I still wonder if an injector is clogged. Though they do only have about 50K on them, so I would find that hard to believe. I idle real nice and it runs smooth for the most part. It just has a small misfire/bobble between 1500 and 3500 rpm when I get on it in second gear. Very strange.
"In Oldskool we trust"
As expected, the crank sensor changed nothing. Just wanted to throw that out there for Nickelin Dimer.
"In Oldskool we trust"
Nickelin Dimer mine does it uphill part throttle too, It has never done it under WOT. Didn't get to check plugs or anything, it snowed. Maybe check tomorrow.
This is so annoying though.
I think with what we have happening we need to consider: Fuel Pump, Fuel FIlter, Coils, Plugs, Plug Wires, O2 Sensor, Injectors.
Im now starting to think mine might be the O2, since I had a code awhile back for it I will most likely replace it for the heck of it.
just curious guys is this intermittent problem or all the time? anyone think about checking the fuel pressure regulator, I only ask because the 99 sunfire we had had a similar problem and it was the regulator had gotten some build up in it but it was lose and when just the right angle was acheived it would make the car act up.....
Mine happens SOMETIMES on a ~25 minute highway drive to work and back. Some days it does, some days it doesn't.
O2 sensor life is 100,000 miles according to BOSCH, im replacing that first.
Verocity my uphill steady throttle buck ended up being a bad TPS sensor.
Ryan, if you figure it out LET ME KNOW. My car acts just like that, in second gear only as well. Isn't terrible, but you can just sorta tell it isn't accelerating smoothly under a constant throttle. If I roll into the throttle it's smooth. WOT it's smooth. Just anything over half throttle or a little more and you can tell. Only does it with a steady pedal as I can increase the throttle and it goes away. I have noticed that if I've had my battery unhooked while working on something it seems to go away for a few days.
Verocity wrote:Mine happens SOMETIMES on a ~25 minute highway drive to work and back. Some days it does, some days it doesn't.
O2 sensor life is 100,000 miles according to BOSCH, im replacing that first.
i know i don't own a 2200, but from what i've heard from alot of other members on this site, bosch's products are pretty much garbage for our cars.
this is wierd, my sunfire has a 2200 in it with 260000 kilometers on it and it runs great, doesnt do anything like your guy's cars lol, hope you guy's figure it out
Mine was doing something similar a while back, and once in a while it would throw a VSS code. It would ONLY have problems after it was warmed up all the way, when it was cold it seeemed ok.
I ended up borrowing a scan-gauge and determining it was the TPS causing the problem. I just went to a local yard and grabbed a sensor off the newest 2200 i could find. Has been running much better ever since. A new TPS is not cheap, but you can get one from the yard either for cheap, or for the "cost of entry" to the yard
. worth a shot IMO if you have a yard close by
"A car just isn't a car without a little blood, sweat, and beers." -- Shadowfire
