Random multiple cylinder misfire detected
12-07-2009, 02:56 AM
#21
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did you check the gap before you installed them?
it says they are pre gapped but ive installed probably 6 sets of NGk iridiums and they have always been different gaps. on each plug.
post a datalog, but I assume your tune is just putting you super rich
it says they are pre gapped but ive installed probably 6 sets of NGk iridiums and they have always been different gaps. on each plug.
post a datalog, but I assume your tune is just putting you super rich
12-07-2009, 03:06 AM
#22
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did you check the gap before you installed them?
No
it says they are pre gapped but ive installed probably 6 sets of NGk iridiums and they have always been different gaps. on each plug.
What should they be? .44?
post a datalog, but I assume your tune is just putting you super rich
No
it says they are pre gapped but ive installed probably 6 sets of NGk iridiums and they have always been different gaps. on each plug.
What should they be? .44?
post a datalog, but I assume your tune is just putting you super rich
12-11-2009, 01:26 AM
#25
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greddy turbo, emanage ult.,aam fuel delivery, 13psi, aem boost and afr gauge, hks evc (not installed), inj size i dont know how to check, recirc valve. Happened since day one, I got the car like this.
12-11-2009, 01:43 AM
#27
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found this:
A P0300 OBD DTC code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.
Symptoms
Symptoms may include:
A code P0300 may mean that one or more of the following has happened:
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.
Looks like I have some work ahead of me
A P0300 OBD DTC code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.
Symptoms
Symptoms may include:
- the engine may be harder to start
- the engine may stumble / stumble, and/or hesitate
- other symptoms may also be present
A code P0300 may mean that one or more of the following has happened:
- Faulty spark plugs or wires plugs replaced and wires look fine
- Faulty coil (pack) How do I test them
- Faulty oxygen sensor(s) relpaced
- Faulty fuel injector(s) How do I check ?
- Burned exhaust valve?
- Faulty catalytic converter(s) no cat
- Stuck/blocked EGR valve / passages Does this apply?
- Faulty camshaft position sensor anyway to test this or would the car give another code if this was bad?
- Defective computer Doubt it
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.
Looks like I have some work ahead of me
12-15-2009, 05:10 AM
#30
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oh thanks for the quick reply crush! i will try to mess with the AEM FIC on my own, the shop forgot to give me back my USB cable. I really cant do anything at the moment and really busy training for another deployment. I will ask questions at the AEM FIC thread we have on here.
12-29-2009, 05:45 AM
#31
^^^^^ i had the same problems with my car. rough idle, long time cranking to start, and stumbles at WOT..... did the resistor mod for the aem fic, WORKS PERFECT. you shuld def try that out, i mean before i did it my $17,000 car was running like a $500 POS, but after the starts/idle are almost better thank stock. just my two cents
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