Help help help random misfires!!!
Your problem lies within these 3 sources
MAF
Injectors
Coils
One by one, disconnect and reconnect the cable to the coil packs also the Injectors. I can bet it's either the injectors or coils.
If not the car wouldn't even turn on at all. a dirty maf can cause sputtering but usually never misfires.
MAF
Injectors
Coils
One by one, disconnect and reconnect the cable to the coil packs also the Injectors. I can bet it's either the injectors or coils.
If not the car wouldn't even turn on at all. a dirty maf can cause sputtering but usually never misfires.
I'm no expert but I'll assume the lack of back pressure from the missing cats (or honeycomb in them) is throwing off the pre and post cat 02 sensor readings and as a result leading to the miss.
Also, there's a reason why your cats became plugged. The most common cause is an excessive fuel mixture (running too rich). The likely culprit is an exhausted o2 sensor(s). Cats also become plugged from an overheating condition. You don't state why your original engine failed? You've got me wondering now...
Also, there's a reason why your cats became plugged. The most common cause is an excessive fuel mixture (running too rich). The likely culprit is an exhausted o2 sensor(s). Cats also become plugged from an overheating condition. You don't state why your original engine failed? You've got me wondering now...
Its been spelled out twice in the thread.
I highly doubt the source of the mis has anything to do with ignition.
You said it yourself. Test pipes and what you had done are similar. Aside from one thing; the gutted cats likely causing power loss. So what must you do when you change cats out for test pipes.
.....
.....
Misfires are caused by 3 variables, well technically 4.
Fuel(quality), Spark, Injector, MAF reading
Gutted catylitics have nothing to do with that.
How can that be so?
Look at how everyone that is using test pipes is not misfiring. By removing the contents of your catylitics you are not losing power, you're only shifting the power to a different section of the power band. (The law of Conservation of Energy) "Matter cannot be created nor destroyed it only changes form".
Same applies with any engine. Yes you "feel" a loss of torque at a given RPM, but that torque is then carried over to another section of the RPM band (in other words you didn't lose power, you just moved it elsewhere).
Why fuel quality?
Perhaps he had a bad batch of gasoline, contained a bit too much E85, or even water? Fuel quality can affect a cars performance. Usually not so much so that it makes the car misfire, but it's a variable.
Misfires are caused by 3 variables, well technically 4.
Fuel(quality), Spark, Injector, MAF reading
Gutted catylitics have nothing to do with that.
How can that be so?
Look at how everyone that is using test pipes is not misfiring. By removing the contents of your catylitics you are not losing power, you're only shifting the power to a different section of the power band. (The law of Conservation of Energy) "Matter cannot be created nor destroyed it only changes form".
Same applies with any engine. Yes you "feel" a loss of torque at a given RPM, but that torque is then carried over to another section of the RPM band (in other words you didn't lose power, you just moved it elsewhere).
Why fuel quality?
Perhaps he had a bad batch of gasoline, contained a bit too much E85, or even water? Fuel quality can affect a cars performance. Usually not so much so that it makes the car misfire, but it's a variable.
Facepalm.
The gutted cats are likely causing the probably dirty as sh|t o2 sensors to read incorrectly. Which can lead to the ecu and all the bits that make **** happen miscommunicating. Though all listed topics are viable, it's one simple thing to consider (I wouldnt have mentioned it if I hadnt witnessed the problem in person).
The gutted cats are likely causing the probably dirty as sh|t o2 sensors to read incorrectly. Which can lead to the ecu and all the bits that make **** happen miscommunicating. Though all listed topics are viable, it's one simple thing to consider (I wouldnt have mentioned it if I hadnt witnessed the problem in person).
Last edited by forweareLegion; Oct 14, 2010 at 07:43 PM.
Hey guys update, Car is fixed. It was my o2 sensor it was burned out from my last engine. It wasn't reading air properly. Changed two front o2 sensors and reset ecu and now it is fine.
Thanks for all you guys advice help me out a lot made us check everything.!
Thanks for all you guys advice help me out a lot made us check everything.!
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