Plugs fouled after 2 weeks?
#16
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Does it only happen when the car warms up? And I mean right when it warms up. Not after you drive for 50 miles. Does it only happen when you are idling and just starting out? Or also on highway cruising? When does it happen most often? How are your motor mounts? I assume good.
I still think it is moisture.
Here's what happens. When you first start your car - it is DEEP down in there - does not cause any interference.
As the car warms up - it tries to evaporate. but it can't escape. So now it has expanded into water vapor - taking up more space and interfering with an otherwise perfect spark.
There or no sensors to detect it so no check lights come on.
Also with the spark plug wires resistance increases as temp goes up, but you can't test the wires at operating temp obviously. So you might not be able to rule that out.
Sorry man I respect you for taking you car apart again...I guess you got my email. I thought maybe it was the TB gasket but you must have replaced that, too, if you followed the instructions to the letter.
I have been having some probs lately with my email so if you didn't get it I will try again.
I still think it is moisture.
Here's what happens. When you first start your car - it is DEEP down in there - does not cause any interference.
As the car warms up - it tries to evaporate. but it can't escape. So now it has expanded into water vapor - taking up more space and interfering with an otherwise perfect spark.
There or no sensors to detect it so no check lights come on.
Also with the spark plug wires resistance increases as temp goes up, but you can't test the wires at operating temp obviously. So you might not be able to rule that out.
Sorry man I respect you for taking you car apart again...I guess you got my email. I thought maybe it was the TB gasket but you must have replaced that, too, if you followed the instructions to the letter.
I have been having some probs lately with my email so if you didn't get it I will try again.
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This moisture concept doesn't really sound like the cause. And I have never heard of this "DEEP DOWN" thing...... Also the title mentions fouled plugs, have you re-checked them to ensure that is the case (I didn't see where you mentioned this). If so that is a sign that the system is delivering too much fuel. This could be anything from a false lean condition, to an open injector, or one that is open too long (duty cycle issue).
An exhaust leak is an example that could create a false lean reading, where air enters the exhaust system after the cylinder head and makes it appear as if the car is lean to the O2 sensors, thus wanting it to add more fuel and creating a rough idle. Have you noticed any change in the sound of the car (louder)?
You can test your plug wires, by pulling one wire at a time to see if there is any change in the idle of engine while the car is running. You should hear it slow since it will be operating on one less cylinder. That will tell you that you have spark and that the cylinder is firing properly. If you come to one where the idle doesn't change, that will let you know there is an issue with that cylinder.
Now if it is just a mild hesitation then you could easily just have a vacuum leak someplace (throttle body gasket?). You also mentioned that you changed the cap and rotor. Have you checked your timing?
Check the easy stuff and work from there. Best of luck.
An exhaust leak is an example that could create a false lean reading, where air enters the exhaust system after the cylinder head and makes it appear as if the car is lean to the O2 sensors, thus wanting it to add more fuel and creating a rough idle. Have you noticed any change in the sound of the car (louder)?
You can test your plug wires, by pulling one wire at a time to see if there is any change in the idle of engine while the car is running. You should hear it slow since it will be operating on one less cylinder. That will tell you that you have spark and that the cylinder is firing properly. If you come to one where the idle doesn't change, that will let you know there is an issue with that cylinder.
Now if it is just a mild hesitation then you could easily just have a vacuum leak someplace (throttle body gasket?). You also mentioned that you changed the cap and rotor. Have you checked your timing?
Check the easy stuff and work from there. Best of luck.
Last edited by WhiteTiger; 02-23-05 at 11:33 AM.
#18
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I was just saying gravity would keep the water lower below the spark plug when cold. I don't see why that wouldn't make sense.
If it was a mixture issue or vaccum leak I would suspect a CEL light would be triggered, bet hey I don't know. He checked his plugs and they all looked fine.
If it was a mixture issue or vaccum leak I would suspect a CEL light would be triggered, bet hey I don't know. He checked his plugs and they all looked fine.
Originally Posted by WhiteTiger
This moisture concept doesn't really sound like the cause. And I have never heard of this "DEEP DOWN" thing......
#19
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Originally Posted by dundfaukus
I finally got around the check out the wires, the yall had good resistance, less than 25k ohms.
I also cleaned out my TB.
Car still seems to miss and shudder . One thing I did notice is there was little bit of oil on my 6th cylinder spark plug wire. The plug was dry though.
Other than that, I inspected each plug and they all seemed to have normal color, tannish white. Their gapping is fine as well.
I am pretty sure my ignition system is OK. Question is, what is still causing the car to act like this...?
I also cleaned out my TB.
Car still seems to miss and shudder . One thing I did notice is there was little bit of oil on my 6th cylinder spark plug wire. The plug was dry though.
Other than that, I inspected each plug and they all seemed to have normal color, tannish white. Their gapping is fine as well.
I am pretty sure my ignition system is OK. Question is, what is still causing the car to act like this...?
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#20
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Here is the list of final items to check according to he service manual for poor driveability/hesitation/poor acceleration
1)SWITCH CONDITION SIGNAL CIRCUIT = THROTTLE POSITION SENSOR IDL SIGNAL
2) volume air flow meter circuit
3) injector circuit
4)fuel pump control circuit
all the rest of the items you've checked, also check the coolant sensor as this has alot to do with the engines performance.. There should be one sensor for the gauge and another for the ECM to determine tuning. Keep us posted!
1)SWITCH CONDITION SIGNAL CIRCUIT = THROTTLE POSITION SENSOR IDL SIGNAL
2) volume air flow meter circuit
3) injector circuit
4)fuel pump control circuit
all the rest of the items you've checked, also check the coolant sensor as this has alot to do with the engines performance.. There should be one sensor for the gauge and another for the ECM to determine tuning. Keep us posted!
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#21
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Pianoman- The problem is pretty random, like this morning the car started and idled fine, accelerated just like nothing was wrong. Until I got to the end of the street, then I noticed it beginning to hesitate and stuff. Some mornings the problem starts off right away. I notice at stop lights the car will become OK, idle will be smooth...once I tap the gas then it'll start acting like its missing. I had the moisture problem before when I washed the car, and I made sure to use my wetvac to suck up all water and let the car dry overnight(it worked fine after that). This time when I took it apart, I was checking EVERYWHERE for possible moisture or leaks from coolant line into wells, but found nothing. BTW I got your email about the plugs, thanks.
turbogs300- Is there any BGB or something online that I can look at so I know how to check those things...or at least know what resistance they should have, etc.
Thanks again for all of ya'lls help.
turbogs300- Is there any BGB or something online that I can look at so I know how to check those things...or at least know what resistance they should have, etc.
Thanks again for all of ya'lls help.
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