98 Suburban Help!!!
Traffic Hank
02-29-2008, 10:02 PM
I had my fuel pump go out two weeks ago and I replaced it and the fuel filter. Now the truck will not idle, I keep on getting a OBDII code P0300 random missfire. I have changed the plugs and wires with no help. I was told that it could possibly need throttle position sensor and or it could be a bad fuel pump. Any helpfull suggestions would be greatly appriciated. Thanks Traffic Hank
2.2 Straight six
02-29-2008, 10:08 PM
you may need to bleed the fuel system although it's unlikey.
Traffic Hank
02-29-2008, 10:23 PM
Thanks for the thought but I did that when we tested after the install. Thanks
UncleBob
03-01-2008, 06:35 AM
there's no gas engine that you need to bleed the fuel system on. single line setups, such as the dodge's, they self purge rapidly. Two line setups, such as the truck in question, purge pretty much instantly
random misfires can be caused by many things. If its the only code, I would suspect a bad coil or cap/rotor issues. Clogged cat converter
There's a list for yah anyway
TPS would set a code
random misfires can be caused by many things. If its the only code, I would suspect a bad coil or cap/rotor issues. Clogged cat converter
There's a list for yah anyway
TPS would set a code
Traffic Hank
03-01-2008, 01:47 PM
am in the process of new plugs wires and rotor cap- thanks those were my next thoughts also-I'll let you know Traffic Hank
Traffic Hank
03-01-2008, 10:23 PM
Thanks for the input UncleBob. It was a good try but after changing out the cap and roter it still has the same problems.
UncleBob
03-02-2008, 06:32 AM
Thanks for the input UncleBob. It was a good try but after changing out the cap and roter it still has the same problems.
check the cat?
check the cat?
MobileMom
03-03-2008, 08:35 PM
Try running some fuel injector cleaner through the system. Clogged fuel injectors can cause the P0300 code, and random misfires. If the fuel injector cleaner doesn't quite do the trick, you might to take them out and clean them, or have a shop rebuild your injectors.
Clogged fuel injectors can cause most of the symptoms of bad spark or bad gas issues.
Another thing that you might want to check, is your EGR valve. If it is not circulating properly, it will cause all those lovely problems as well.
I hope this helps!
If your looking for more information, check out
http://www1.autozone.com/UseCase,S001/UserAction,viewSimpleDiagInfo/Parameters,info/getInTheZone.htm
or hit me up on my page at http://www.myspace.com/acceleratedautomotive
Clogged fuel injectors can cause most of the symptoms of bad spark or bad gas issues.
Another thing that you might want to check, is your EGR valve. If it is not circulating properly, it will cause all those lovely problems as well.
I hope this helps!
If your looking for more information, check out
http://www1.autozone.com/UseCase,S001/UserAction,viewSimpleDiagInfo/Parameters,info/getInTheZone.htm
or hit me up on my page at http://www.myspace.com/acceleratedautomotive
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