Recently bought 98 with some problems/ please help!!

[joseflores0609]

Hi everyone im new to this site but hope to contribute and get as much knowledge as i can. I HAVE A 98 SPORT WITH 4.0 V6 When i bought this truck about 2 months ago the cel light was already on but it ran fine so i bought it. Havent had trouble with it, hasnt turned off or anything but that cel light has been bothering me. I had a complete tuneup done (spark plugs, wires, oil, gas filter, oil filter, air filter) but since i bought the truck it runs really rough until it warms up then all is fine...lately its even doing it while is already warm..itll run smooth but you can tell it gets jumpy even at idle and a slight misfire, doesnt seem to waste a lot of gas, but what do i know i bought it with the cel light on so it can be even better for all i know.lol. When i did the tuneup it wasnt including the cel light fix. I checked it today and it gave me 4 codes!! Now i need your guys help in determining whats wrong with my truck as i am going to texas from california(long drive) here are the 4 codes i got:

1)o2 sensor heater circuit malfunction. Bank 1 sensor 1

2)insufficient switching o2. Bank 1 sensor 1/lean

3)random/multiple cylinder misfire detected

4)system too lean bank 2

please help me out...i know some of you have had problems similar..pass me your knoldge and let me know what you think..thanks ahead of time

 

[ExploringNC]

sound like you need an O2 sensor and the m0012 kit installed. Do a search on the M0012 kit but that will usually fix the running lean issues.

 

[joseflores0609]

how do i know wich of the o2 sensors?

 

[jlsparky7]

how do i know wich of the o2 sensors?

Buy a haynes manual. It tells you what all the codes mean i believe.

 

[gijoecam]

Don't waste your money on the oxygen sensors until you verify there is no intake leak. I, too, suspect the 00M12 service kit for the lower intake manifold gaskets is the root cause of most of the problems. Common problem, $35 and a couple of hours is the simplest solution.

 

[ThePhoenix]

also dont see mention of fuel filter. I ran "lean" with a bad o2 sensor until I changed the fuel filter.. then no CEL...also did you disconnect the battery for 10 min?

 

[marragtop]

Yeah, if you've been driving it for months with the CEL on, I suggest resetting the codes and pulling them again to see what they say.

 

[joseflores0609]

i did have a full tuneup including the fuel filter but i never reset my battery not for 10 minutes..ima do that right now and run codes later again.

my father was a mechanic so i have a little above average knowledge of mechanic work, is the00m12 service kit an easy install or would you pay someone for this? also do i have to get the kit at the dealer or can i get at autozone? if so what parts am i asking for? i am aware that there is a writeup for this but just want to know your thoughts

thanks

 

[jlsparky7]

i did have a full tuneup including the fuel filter but i never reset my battery not for 10 minutes..ima do that right now and run codes later again.

my father was a mechanic so i have a little above average knowledge of mechanic work, is the00m12 service kit an easy install or would you pay someone for this? also do i have to get the kit at the dealer or can i get at autozone? if so what parts am i asking for? i am aware that there is a writeup for this but just want to know your thoughts

thanks

No offense but just because you paid for it doesnt mean it was done. Are you sure they changed the fuel filter?

Not doubting you just making sure.

 

[joseflores0609]

lol....i know for a fact.i marked the fuel filter with a sharpie..the new one wasnt even the same color when i got it back...... so i know the work was done!

 

[jad2411]

A que parte de Texas vienes?