Running rich and idling high..

[Ryan_V]

The 92 240sx I just bought is running quite rich..I got gas in the oil and mileage is suffering..

I changed the plug's already..They were gapped at .060 when I took them out- I corrected the plugs and it run's the same..imagine that!

I bought a complete set of injector seal kits that I'm going to install today.

Any more ideas I could try??

Also it idle's at 1500 rpm after it warms up..The FSM say's to check the AIV...but then it doesn't say how to check the AIV..

Anybody know what you can do to the AIV to see if it works right??

Other than these issue's the car run's great..and doesn't bog..die..backfire..whatever..

btw..I did search for the "running rich" symptom and i didn't find any solutions to the problem..

ThanksRyan

[Ryan_V]

I did search and find the procedure the FSM says to try...."squeeze the hose and see if idles drops"

I'll give this a go and see what happen's

[tonynalli]

run the diagnostics on your car. and check your fuel pressure regulator..

[SimpleEnigma]

Check your coolant temp sensor. Mine was doing the same, and changed it, fixed the running rich prob. should also fix the idle if this is the culprit. it fixed my mixture issue, but it is still idling at like 1100-1300 after the engine has warmed, up. I think i have a problem in my engine harness.

[SOHCSE]

If you have gas in your oil, I would think you probably have some sort of injector leak. Run a search on gas in oil. There are a lot of helpful posts on the subject and some troubleshooting information to boot!

Good luck,Matt

[Ryan_V]

I did a search for "gas in oil"

Most of the posts say that the injector o-rings might be gone or they are leaking..

I just don't understand how the o-ring could keep the injector from leaking into a cyl? Don't the o-ring's seal the injector so that they don't spew or leak fuel into the engine compartment?

I've seen the injectors themselves be cracked and that along with a bad o-ring caused fuel seepage..

A injector that has a leaky nozzle will seep into the cyl or that a coolant temp sensor or ECU coolant sensor would be faulty and the ECU would be tricked into throwing excess fuel into the mix.

O2 sensor...well I've had them cause slight bucking when bad but not a rich condition...

I'm going to pull the fuel rail off and check for a seeping injector..

[JDMEnthused]

eh.. you would be surprised when your talking about o2 sensors, i replaced one on my sisters boyfriends S13 and his gas mileage went way up and it was running a pretty clean AFR...

i would just replace that shizz though.

[Ryan_V]

Well the fuel rail doesn't want to come off...the front two injectors move fine, but the rear two act like there's something hidden holding them in..

Does the FPR have to come off first?

Thanks

[SOHCSE]

If it's a SOHC , you just need to remove the two bolts holding the rail on and it should just lift off.

Hrmmmm, just noticed that it is a DOHC that has side feeds, sorry, Ill do a little searching, I know there is a lot of posts about removing that.

I only have experience with the SOHC.

[babowc]

i have the same problem.. running quite rich, i think its the coolant temp sensor as well for me..i've replaced the o2 and plugs, i just need to return my wrong set of wires and get new ones..

:sigh: anyways, the idle being high could be a result of the idle control screw.. its on the bottom left (iirc) of your intakemani.. a flathead screwdriver and turn it, forget which way for + or -..

[Ryan_V]

I removed that big hose that split's off the air intake tube right near the throttle body and capped off the hole...

The car now idles @1000-1100rpm..I didn't get the car all that warmed up, but that's a noticable improvement if you ask me..

I also pushed on the AIV hose to see if the idle fluctuates after warm and it doesn't...

I still need to get new wires as well and change the oil to see if I get gas in the oil after capping off that MASSIVE metered air leak...

Thanks for everyones input..I'll post my result's this weekend...

[Ryan_V]

Hrmmmm, just noticed that it is a DOHC that has side feeds, sorry, Ill do a little searching, I know there is a lot of posts about removing that.

I searched and couldn't find much about removing the DE fuel rail...It seem's like something at the rear of the rail near the FPR is holding it tight...I removed the two main screws,the one at the valve cover to move the harness outta the way and there's another screw that holds the fuel line...I can get the front two injectors to move out, but the rears are tight!!!