Need help, rough idle after "spirited" driving
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Well, subject line tells the story for the most part...
I was doing some "spirited" driving on the way to work (5:30 AM, roads were pretty empty) yesterday, car was running great, running 3-4k RPMs with the new 3.73 gears in back, for maybe 10-15 miles). When I pulled into the parking lot at work and the RPMs came to idle, the engine started chugging really hard, and surging.
I let it idle while I fired up the AutoTap, and it finally did set a code after shaking and idling there for a minute. P0300, so I turned off the car and went in my office to get on teh net and check the code. Random misfire detected, two P0300 codes, both on cyl #7. I went back out and checked the #7 plug wire for snugness, looked fine. Cleared the codes, and started the car back up, rough idle at first but rapidly cleared up. Drove fine the rest of the day.
I also noticed I'm getting a little white smoke out of the exhaust that I never noticed before.
Last night on the way home from work it started doing the rough idle thing again at stoplight idle (no prior spirited driving this time, normal highway driving). No codes set, but I can feel something isn't idling right and the car is shaking a bit, almost like a mild cam...
It only does it apparently after its warmed up. I'll be checking the plugs this weekend. Car has new fuel and air filters, good gas. The plugs in it are about 12k mile old TR-55s at .059 stock gap. I looked for obvious vacuum leaks and didn't find any. Could be EGR seal again, but fuel trims aren't maxed out, they look fine...
Anyone have any insight ?
Thanks !
BadAss30th
[ March 07, 2002: Message edited by: BadAss30th ]</p>
I was doing some "spirited" driving on the way to work (5:30 AM, roads were pretty empty) yesterday, car was running great, running 3-4k RPMs with the new 3.73 gears in back, for maybe 10-15 miles). When I pulled into the parking lot at work and the RPMs came to idle, the engine started chugging really hard, and surging.
I let it idle while I fired up the AutoTap, and it finally did set a code after shaking and idling there for a minute. P0300, so I turned off the car and went in my office to get on teh net and check the code. Random misfire detected, two P0300 codes, both on cyl #7. I went back out and checked the #7 plug wire for snugness, looked fine. Cleared the codes, and started the car back up, rough idle at first but rapidly cleared up. Drove fine the rest of the day.
I also noticed I'm getting a little white smoke out of the exhaust that I never noticed before.
Last night on the way home from work it started doing the rough idle thing again at stoplight idle (no prior spirited driving this time, normal highway driving). No codes set, but I can feel something isn't idling right and the car is shaking a bit, almost like a mild cam...
It only does it apparently after its warmed up. I'll be checking the plugs this weekend. Car has new fuel and air filters, good gas. The plugs in it are about 12k mile old TR-55s at .059 stock gap. I looked for obvious vacuum leaks and didn't find any. Could be EGR seal again, but fuel trims aren't maxed out, they look fine...
Anyone have any insight ?
Thanks !
BadAss30th
[ March 07, 2002: Message edited by: BadAss30th ]</p>
#2
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The white smoke thing is a little alarming. Usually only coolant will cause "white smoke". I would pull the plugs and check for any green tint which would show coolant loss in that cylinder.Even just a little consumption can intermittently foul the plug enough to cause a rough idle and some miss fire. Of course it could be something else but the white smoke can be a signal to not ignore.
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Ewwww, I hadn't thought of that. Could be head gasket has let go around that cylinder and is leaking coolant in... Hope not. <img src="gr_sad.gif" border="0">
It'd be a shame if I had to do heads and cam as a result of this now wouldn't it. <img src="gr_grin.gif" border="0">
Any other thoughts ?
BadAss30th
It'd be a shame if I had to do heads and cam as a result of this now wouldn't it. <img src="gr_grin.gif" border="0">
Any other thoughts ?
BadAss30th
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Could be a broken Pushrod too.
I would pull the valve cover on that side and have a peak <img src="gr_grin.gif" border="0">
Chris
I would pull the valve cover on that side and have a peak <img src="gr_grin.gif" border="0">
Chris
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[quote]Originally posted by Chris ARE 360:
<strong>Could be a broken Pushrod too.
I would pull the valve cover on that side and have a peak <img src="gr_grin.gif" border="0">
Chris</strong><hr></blockquote>
in an auto? <img src="images/icons/confused.gif" border="0">
<strong>Could be a broken Pushrod too.
I would pull the valve cover on that side and have a peak <img src="gr_grin.gif" border="0">
Chris</strong><hr></blockquote>
in an auto? <img src="images/icons/confused.gif" border="0">
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I am skeptical about it being a pushrod too, no recent hits off the limiter and no missed shifts (a4).
I'm gonna check the oil when I get out for lunch to see if there's any coolant mixed in with it... Cross your fingers. <img src="gr_stretch.gif" border="0">
Thanks for the help fellas, keep it coming...
BadAss30th <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />
Update edit : The oil looks fine, can't see any water or coolant on the dipstick. Got some factory plugs while I was out, will check and swap tonight. Thanks !
[ March 07, 2002: Message edited by: BadAss30th ]</p>
I'm gonna check the oil when I get out for lunch to see if there's any coolant mixed in with it... Cross your fingers. <img src="gr_stretch.gif" border="0">
Thanks for the help fellas, keep it coming...
BadAss30th <img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />
Update edit : The oil looks fine, can't see any water or coolant on the dipstick. Got some factory plugs while I was out, will check and swap tonight. Thanks !
[ March 07, 2002: Message edited by: BadAss30th ]</p>
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OK, swapped in factory plugs and wires last night.
<img src="graemlins/gr_guns.gif" border="0" alt="[guns]" /> plug #8 <img src="graemlins/gr_punch.gif" border="0" alt="[fight]" />
Measured old Taylor wires with ohmmeter, 4 of them were around 200 ohms, the other four ranged from 2k to 25kohms ! Needed to be replaced anyway obviously. Just goes to show more expensive isn't always better. Stockers all measured right around 300 ohms.
12k mile NGK TR55 plugs looked okay, but I replaced them anyways.
I had the battery disconnected for a few hours, so after the swap I idled for 5 min, 5 min with A/C on, then 5 more min with it off. No stumble. Thought I had it.
It ran great on the way to work this morning, but after pulling into the parking lot and letting it idle, the intermittent stumble is back. <img src="gr_images/icons/mad.gif" border="0">
I'm probably gonna take it to the dealer this morning unless someone posts something brilliant that I haven't thought about yet...
Any ideas ?
BadAss30th
<img src="graemlins/gr_guns.gif" border="0" alt="[guns]" /> plug #8 <img src="graemlins/gr_punch.gif" border="0" alt="[fight]" />
Measured old Taylor wires with ohmmeter, 4 of them were around 200 ohms, the other four ranged from 2k to 25kohms ! Needed to be replaced anyway obviously. Just goes to show more expensive isn't always better. Stockers all measured right around 300 ohms.
12k mile NGK TR55 plugs looked okay, but I replaced them anyways.
I had the battery disconnected for a few hours, so after the swap I idled for 5 min, 5 min with A/C on, then 5 more min with it off. No stumble. Thought I had it.
It ran great on the way to work this morning, but after pulling into the parking lot and letting it idle, the intermittent stumble is back. <img src="gr_images/icons/mad.gif" border="0">
I'm probably gonna take it to the dealer this morning unless someone posts something brilliant that I haven't thought about yet...
Any ideas ?
BadAss30th