Did some Mainence and now CEL came on. Too Lean

[electronics4u]

Need a little help here. I did these things yesterday.

- I replaced the spark plugs with OEM sparkplugs. (What a PITA!!)
- I cleaned the MAF. I used CSC to clean it off.

Today, the CEL comes on with code 151 I think at least that is what the Autozone dude told me. (Should have written it down.) Bottom line is that I am running too lean. He suggested that I may have some air in the fuel line etc.


What do you guys think?

Thanks for your help!!
:nono:

 

[Grezdlitn]

Air in the fuel Line is Bunk! If you removed the maf for cleaning a to lean condition suggests that you didn't get a vaccum line reconnected properly or perhaps one is split or damaged. I'd look those over first.

Good luck!

 

[electronics4u]

I also plan on replacing the fuel filter. Considering it has not been changed in who knows how long. Think that could be it? I will check out the vacuum lines. Hopefully that is what it is.

Thanks.

 

[YotaZach85]

Lean codes normally aren't due to fuel pressure, it's usually a bad sensor or a vacuum leak so I don't think the fuel filter will fix you up and there definitely isn't air in the fuel line. Get a can of starting fluid and spray around all of the vacuum lines with the truck at idle at look for a change in RPM's. Check your wires at the MAF, too. Did you gap the spark plugs to spec?

 

[electronics4u]

Lean codes normally aren't due to fuel pressure, it's usually a bad sensor or a vacuum leak so I don't think the fuel filter will fix you up and there definitely isn't air in the fuel line. Get a can of starting fluid and spray around all of the vacuum lines with the truck at idle at look for a change in RPM's. Check your wires at the MAF, too. Did you gap the spark plugs to spec?

I didn't gap them. Will be a great learning if that is it. When you mentioned the sensor could be bad. How could I tell? When you mention to check the wires by the sensor, do u mean spray them too? Overall the truck seems to be running ok. Slow to shift and it lags a bit at take off.

 

[t4r4life]

p0151 is O2 Sensor Circuit Low Voltage and most likey is the one before the cat which is a air/fuel ratio sensor that can cause you to run lean if it got worn out, they have one on amazon Amazon.com: Denso 234-4162 Oxygen Sensor (Air and Fuel Ratio Sensor): Automotive

 

[LittleCaesar]

I don't think there is a PO151 but instead a PO171.

Gap the plugs to .043~.044. Use a little anti seize on the threads and dielectric grease in the boot.

Check the wiring to the MAF and the vacuum connections around the intake. When you used CRC, it was the dedicated MAF cleaner correct?

Try clearing the memory by disconnecting the negative battery cable for 3+ minutes.

 

[electronics4u]

Thanks for all of your help guys. The issue turned out to be user error. :bash: I had the hood up and was telling my wife what was going on and was just saying, I don't know what a vacuum hose is, then I saw the hose that I forgot to reconnect.

Dodged a bullet this time.

Though I think that I will have to take a moment to spray some carb cleaner around the hoses to see if there are any leaks. The car still seems to idle a little rougher than I think it should. It is weird since it seems like it idles rough in regular intervals. Like in 1 second intervals. Ex smooth...rough...smooth...

If you have any thoughts just send them my way.

 

[YotaZach85]

Thanks for all of your help guys. The issue turned out to be user error. :bash: I had the hood up and was telling my wife what was going on and was just saying, I don't know what a vacuum hose is, then I saw the hose that I forgot to reconnect.

Dodged a bullet this time.

Though I think that I will have to take a moment to spray some carb cleaner around the hoses to see if there are any leaks. The car still seems to idle a little rougher than I think it should. It is weird since it seems like it idles rough in regular intervals. Like in 1 second intervals. Ex smooth...rough...smooth...

If you have any thoughts just send them my way.

Clear the code and see if the light comes back on just to be sure that was the problem. I would pull all the spark plugs back out and gap them to .043-.044. You might want to look up how to clean the throttle body and IAC valve, the rough idle might be a sticky IAC valve.

 

[ryankmasuda]

Did you install plugs with the dual prong? I picked up some "OEM" plugs from the auto store and they gave me single pronged plugs. In the past it has thrown a code. Since then I won't leave the store till I inspect the plugs

 

[electronics4u]

Did you install plugs with the dual prong? I picked up some "OEM" plugs from the auto store and they gave me single pronged plugs. In the past it has thrown a code. Since then I won't leave the store till I inspect the plugs

I made sure they were dual prong before I left the store. I am not too excited to get back in there. May need to pick up a few Canadian beverages first.

On another note while I am in there, I can start replacing some corroded bolts and take the stock running boards off. Will post some pics later.