random misfire code
timespy
04-20-2009, 02:49 PM
Any ideas here? Changed plugs, cleaned throttle body, no obvious vacum leaks. 2002 rodeo, 3.2 v-6 4x4. This this is also giving me a flashing service engine light at, and above 2000 rpm, but no light below. Runs rough and sometimes stalls at idle, no black smoke, and the old plugs were clean and dry when i pulled them. Im also getting a low egr flow code at times. This is driving me batty, any help would be greatly appreciated. Ive looked all over for info, and found quite a bit, but this just cant be that complicated.
amigo-2k
04-20-2009, 05:15 PM
"Runs rough and sometimes stalls at idle"
Sounds like a leaking intake manifold gasket.. I've had mine replace 2x in 70k..... very common issue.... See the FAQ link below for more information....
Sounds like a leaking intake manifold gasket.. I've had mine replace 2x in 70k..... very common issue.... See the FAQ link below for more information....
Andie_J
04-20-2009, 10:32 PM
:smile::smile:For that model you need to use only the spark plugs listed in the manuel. I did and I still got the random misfire code. Drove me crazy, till I removed almost all the anti-seize and that di-electricail grease. No more codes. But even with the code it seemed to run fine.:smile::smile:Andie
Cat Fuzz
04-21-2009, 12:26 AM
Check that your fuel pressure is where it's supposed to be.
amigo-2k
04-21-2009, 10:46 AM
and one of the six coils over the plugs is different. if you put the magic one in the wrong spot you will get a mis-fire code.
timespy
04-21-2009, 02:58 PM
Thanks for the advice. I pulled the egr and gave it an intense cleaning...that didnt solve it. The plugs are correct, the coils are correct, the fuel pressure must be good or id think it wouldnt have any power at higher rpms. With the rain this morning it seemed to run really well. No flashing check engine lght today. This weekend ill do the intake manifold gaskets, and see what that does. Perhaps ill pull the 0s sensors and give them a good cleaning as well. Any more advice will be greatly appreciated.
amigo-2k
04-21-2009, 08:07 PM
Did you clean the EGR tube where is exits behind the throttle body?
AWILLIAMS64
04-28-2009, 02:39 PM
I am having the same problem, again, random misfire. I changed the plugs 2 years ago and last year did the intake gaskets and cleaning of the egr tubes, etc. how much should the fuel pressure be?
amigo-2k
04-28-2009, 04:56 PM
You may want to retorque your plugs, i recently have a flashing CEL and i just needed to tighten the plugs because they were loose.
fourwd1
04-30-2009, 03:26 PM
and one of the six coils over the plugs is different. if you put the magic one in the wrong spot you will get a mis-fire code.
Yes, that would be cyl #6. The wire between the coil and the plug is a hair longer then the rest, so if you put one of the other 5 there it does't make perfect contact and you'll get random mis-fires (but no noticeable change in performance).
Also, if you use other than the Denso plugs specified you can get random mis-fires, again with no noticeable change in performance.
Yes, that would be cyl #6. The wire between the coil and the plug is a hair longer then the rest, so if you put one of the other 5 there it does't make perfect contact and you'll get random mis-fires (but no noticeable change in performance).
Also, if you use other than the Denso plugs specified you can get random mis-fires, again with no noticeable change in performance.
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