Do It Yourself Tune Up

[Kittamaru]

Used the search function, but didn't find anything terribly informative -

 

What I want to do is tune-up my truck myself... I don't know if it's posible considering I dont' have any fancy equipment, but with just being laid off I need to save cash where I can... the truck needs a tune up as she's running VERY rich at the moment... after new plugs, wires, cap, and rotor is when this started. The MPG is down from where it should be, but improved since the new gear.

 

How hard and/or what is involved in a tune up? Would my Haynes manual really be able to walk me thru it? I figure the biggest part right now is "choking" it back a little... isn't that the set of screws on the throttle body that do that?

[5523Pathfinder]

Do not touch the throttle body screws!!! They are preset and if you move them, you can damaged the trottle chamber!

 

As far as the tune up goes, simple hand tools is all you need. The Cap, Rotor and Fuel filter can be removed with a screwdriver. You will need a ratchet, couple of extensions, wobbly adapter and a spark plug socket(5/8ths), or use the spark plug tool. I would recommend using a vacuum or compressed air to clean the plug holes before you remove the spark plugs as debris may fall into the cylinder (bad, bad, bad). You may have other issues besides needing a tune up. Check the ECU for codes and maybe replace the O2 sensor and go from there.

[Kittamaru]

No no no no no... lol...

 

I already replaced the plugs/wires/cap/rotor. It's running a bit better, but it's running rich. The old plugs I took out were gapped nearly THREE times what they should have been.. think that had something to do with the truck running like crap

 

What I need to do now is bring back how much fuel is being used. I know there's a way to adjust that, just dont' know what it is.

 

Also, AFAIK the O2 checked out fine last time, and my emissions were good before I had the trouble with stuttering (which the new plugs and wires resolved). I guess I could replace it, but I'm pretty well strapped for cash atm... have 1500 total to my name and most of that is dedicated to the wedding plans.

[94extreme]

i don't think you can adjust your richness but since you said it started after you did the tuneup.. check all that again as i bet that is where your problem lies. O2 could be bad without the CEL.. run the diagnostics.. when mine went dead, my truck ran really rich for a while.. if you're at sea level or close, just unplug the O2 and see if there is a difference.. if the o2 is good, there shouldn't be much of a noticeable difference

[5523Pathfinder]

It wouldnt hurt to clean your Air flow meter. See the write up in the how-to section. for some, thats helped a bunch.

[94extreme]

there is good info on cleaning the MAF here.

[Kittamaru]

Aighty, so clean the MAF and pull the O2 - O2 is between the Cat and Straight Pipe, right?

[94extreme]

just unplug it up front. no need to pull it out just yet but check the ecu first and recheck you previous work.

[Kittamaru]

Oh, trust me - I double and triple checked my work, as well as checking and rechecking before I started.

 

I know a little bit of dust and other small particulate fell into the ignition chamber... I blew out the plugs as best I could before removing them, but there was dust underneath the metal o-ring on the old plugs, and they were burnt to hell. It ran rough a little bit after that, but cleared up within a day.

 

As for the O2- I'll give it a shot.

[Kittamaru]

*bumping* this back up

 

Rechecked the plugs, wires, rotor, and cap - all clear there. My next thing is to try cleaning the intake, but it doesn't feel sticky at all so I don't hold too much hope there.

 

I'm thinking of running a load of seafoam in the oil and gas (I'm due for an oil change in a few hundred miles) - what do you guys think of that?

 

EDIT - I haven't gotten to do the O2 yet, but that's because I'm still fighting the appeal - haven't had a chance to dig around too much - I'll get to that this weekend I hope

Edited February 25, 2009 by Kittamaru

[Kittamaru]

Well, I disconnected the O2 sensor and it didn't seem to make any difference 0o' Ran just as well connected as disconnected - not sure if that's good or bad though XD

[Precise1]

Both. It's good that you found a problem and it's bad that you need to buy one.

 

B

[Kittamaru]

So no change = dead O2 then? Damn... well, any chance it could just be fouled? I mean... with my engine running as poorly as it was for a while, as well as the leak in my Y-Pipe I had... *shrugS*

[adamzan]

I thought that if it was running bad and you unplugged the o2, it should run better if the o2 is bad. That is what mine does.

[Kittamaru]

Well, she goes in on Wed for inspection, general once over and tuneup, and I'm letting my mechanic do the oil + coolant and related stuff... while on the job hunt I don't have the energy (or desire atm) to deal with that and since it needs inspected next month figured I'd get it all over with in one shot *shrugs*