Big Problem
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
Likes: 0
From: Round Rock TX
Big Problem ok so on my way to supper I was sitting at a red light then all on the sudden my car jerked the rpm's dropped below the normal 500rpm but as soon as I started to go all was fine. I got home and I put the car in park and the rpm's bounced a little, as soon as i put the car in drive with my foot on the break the car acts up again. also I noticed around 2200-2500 rpms I have a slight ticking sound. hopefully the vid I took will be more help if i can get it up, but has any one dealt with a problem like this? it feels like a misfire or something but I don't have any codes thrown. 
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
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From: Round Rock TX
Something that slight can be so many things. As mentioned....check the plug wires, mainly to make sure none of them are touching any part of the metal exhaust manifold piping...or able to bounce into the metal. That will cause misfires and rough running.
A dirty fuel pump is usual culprit when you have a rough idle, but under acceleration you run fine because the increased fuel pressure overcomes that clog. A fuel filter is around $10.00 and 10 minutes to change....do that.
Run a full can of SeaFoam through 1/4 tank of gas........that will clean any possible dirty injectors. Again, a dirty injector will cause more trouble at idle than while under acceleration.
You could have a failing 02 sensor in the very early stages of death.....and NO, you will NOT get an SES light or code till it gets very bad. Only way to find a failing 02 sensor before you get an SES light or code is a scan to see how they are switching while the engine is running.
Also, clean your MAF........its cheap.
Also, your oil pressure sending unit is failing. Oil pressure gauge needle is bouncing around.
.
A dirty fuel pump is usual culprit when you have a rough idle, but under acceleration you run fine because the increased fuel pressure overcomes that clog. A fuel filter is around $10.00 and 10 minutes to change....do that.
Run a full can of SeaFoam through 1/4 tank of gas........that will clean any possible dirty injectors. Again, a dirty injector will cause more trouble at idle than while under acceleration.
You could have a failing 02 sensor in the very early stages of death.....and NO, you will NOT get an SES light or code till it gets very bad. Only way to find a failing 02 sensor before you get an SES light or code is a scan to see how they are switching while the engine is running.
Also, clean your MAF........its cheap.
Also, your oil pressure sending unit is failing. Oil pressure gauge needle is bouncing around.
.
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
Likes: 0
From: Round Rock TX
well cleaned the MAF and checked all my vacuum lines and they looked good. all plugs and wires are good, ill be looking at the fuel system tomorrow and hope it is something simple.
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
Likes: 0
From: Round Rock TX
I replaced the fuel filter, checked the fuel pressure, rechecked the plugs and wire. I also checked the ALT. and bat, as well as all the wires. so that leaves it to something mechanical . I dont think there is a misfire because it just seems like something is off or out of wack no "cluck pop bang"(technical terms there). i did notice while i was driving it that when i was putting along at 30mph every now and then there was a slight hesitation or lack of power for a split second.
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i've heard of people having issues with a bad maf and never threw a code. the noise was hard to make out in the vid but was it always there or did it start at the same time as the power loss problem?
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It's hard to make out that sound but it almost sounds like you have an exhaust leak at the header gasket. That would throw your o2 sensors off and make it run bad. Maybe try to see if you have a leak there.
I'll bet... this is in the transmission and not in the engine.
If this is only happening while the engine is in drive and your foot is on the brake, it could be the torque converter going out.
If this is only happening while the engine is in drive and your foot is on the brake, it could be the torque converter going out.
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
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From: Round Rock TX
I did notice the far back header on the drivers side is discolored, doesn't that mean that cylinder is running hot? what would cause that?
ans as to the noise it started about 1K miles b4 this problem started, but it was so slight and so isolated (~2K rpm only) I wrote it off as a heat shield rattle.
don't mind the color on the spark plug wire that's just my camera and the firewall has bin discolored like that b4 the headers.
Last edited by Faught; Jun 24, 2011 at 10:50 AM.
TECH Senior Member
Joined: Feb 2009
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how did you test your plugs and wires?in the dark look for arcing from the plug wires.use a multimeter to test for resistance in the plugs.I don't trust plug wires with headers with out heat shield protection.
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
Likes: 0
From: Round Rock TX
actually I rechecked everything I have done, now that I have some sleep and had some daylight. I found some wires that don't "snap" in to the coils and that is about it. I drove the car a little and it does fine when driving, only things are the tick between 2&3K rpm, and an occasional random pop. on a 30 mile trip it pop'ed maybe 4 times randomly and I can hardly hear it, if i had the radio on I would not hear it.
Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
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From: Round Rock TX
I replaced the header gasket, i just got some 8.5mm wires on there and I still have the problem, it is slowly getting worse. I did rev the engine to 1K and kept it there for a short time, when it was at 1K rpm it was very noticeable it kinda reminded me of a car with a big *** cam even sounded like it with the "kathump kathump" and my oil pressure was bouncing like crazy. WTF my poor car, I have to drive it cuz it is my only way to get to school and back but i don't want to cuz I don't want to blow it up.
WTF my poor car, I have to drive it cuz it is my only way to get to school and back but i don't want to cuz I don't want to blow it up. Thread Starter
Staging Lane
Joined: Jun 2011
Posts: 86
Likes: 0
From: Round Rock TX
not yet that's the next thing on my list to do after I check for metal shavings in the oil filter, I'm close to needing to change the oil any way so i might as well check to see if i might have spin a rod bearing.