About a month ago my check engine light came on out of the blue. When I pulled over I smelt gasoline, so I decided to take it to the shop that is right down the street from my house. Their diagnostic said it was a bad O2 sensor, so I let them replace it and the light went off and everything was great again. My 4runner was running as smooth as it was when I bought it about a year and a half ago.

Since then I was toying with the idea of a air intake kit. I removed the stock intake tube and have been pleases with the effects so far, my gas milage went up a little and the truck seemes to be running a little stronger since then.

Long story short, today I'm on a trip for work about an hour and a half from my house and the check engine light comes on. I pull over, same gasoline smell, same stuttering/shakyness. For reasons I can't teally explain I decided to pull the fuse for the EFI as I had done when I removed the intake tube, and for about 15 minutes it ran perfectly again. The light check engine light comes back on and it gets all shaky again soon though.

So is it possible that the removal of the intake had something to do with this? Did the shop down the street screw me over? Is the othero O2 sensor crapping out all the sudden?

Anyone have any insights?

Thanks,
Keith

 

.... wow, sorry that was so long...

-Keith

 

Check your MAF sensor for oil/dirt residue on the hot wire. If there is then clean it off and reset the PCM.

 

What year Runner? If it's after 1995, go to Autozone and get an employee to do an OBD II read on it (it's free). That's what I always tell people that have the "check engine" light on their vehicles after 1995.

 

OBD II read?

I had meant to mention the year in my original post, but I guess I managed to forget. It's a 95 built near the end of the production run for that year. When I had the trouble with it a few weeks back the dealerships first guess was a cracked head gasket. They ran the VIN and told me that it was built late enough in 95 that it isn't covered in the voulentary replacement service plan they were doing and they'd have to hook it up to really find out. I decided to take it to the mechanic down the street from me because it was WAY closer. He later confirmed that it wasn't a gasket problem.

Anyways... should I still take it to have an "OBD II read" done?

Thanks,
Keith

 

Umm no, only after 1995 did vehicles have a general industry standard for diagnostic reads. You might and try ask if they (autozone or Chuck's/Kragen's/Checker's) have an OBD I reader for you truck, that they can do a quick read on with it. If not, then you do have to take it to a mechanic to get the read on the "check engine" light. I mean we can all sit here and guess as to what your problem maybe, but if you can first get a free diagnostic read, it will definitly eliminate your potential for a replacement part where it might not need it.

My guess is that because you removed the intake, did you forget to put a vaccum hose back or did a hose come loose? Is one of your spark plugs misfiring (that will cause it to shake)?