So I was doin a little work on the 97 runner. I put a new airfilter in, new front discs, pads, and ate super blue fluid. I also having spent some time researching seafoam here and in the MR2 forums, I decided to give it a try. I sucked about a quarter can in through a vacuum hose near the beginning of the intake manifold, small amounts at a time, and it smoked a whole bunch. Smoke died down and went for a drive, felt good, smooth, etc... So I ran a little more through, less than a quarter can, and a little smoke came out, less than last time, however the check engine light came on, and I don't know how to get it out. Still runs fine, but that obnoxious light won't go out. Any ideas? Could it have fouled up the oxygen sensor? If so will driving it with a screwed o2 sensor be bad for a couple of days? It is my daily driver right now cause the MR2 don't go in the snow! Thanks for any help.

 

welcome to yotatech .. have the codes pulled

 

Is there a way I can clear the codes to see if it comes back up again? It runs smoother than before the seafoam. Thanks for the welcome. I like the resources these boards offer, the MR2 one is fantastic, and this one seems to be better than the 4x4 wire one. So thanks.

 

pmc,

yes, it could have fouled up the 02 sensor as well as the spark plugs too.

i hate to harsh on you so soon in your first days on YT, but that warning/info has been written several times in several posts, including in the huge seafoam thread

anyways as the post above says, get the code pulled and then search "OBDII" or "OBD2" codes and go from there.

bob

 

No sweat Bob. I did see the warning in the other threads, but figured that at 125k miles, it could use a freshen up. I guess I get some new plugs to throw in there and if it still throws the CEL then get the codes pulled. It's probably due for some new plugs anyway, the ones in there are like 50,000 miles old. What is everybody's favorite plug on the 3.4? I will search, but I just use NGK oem in the past.
Check the new signature! haha

 

yep just use ngk or denso which ever is cheaper hmm ive used seafoam a couple times and i didint have any problems with it guess i got lucky

 

I put seafoam in my 97 V6 and got a check engine light after the engine almost died (it started to stumble slightly while putting seafoam in). The 4Runner ran smoothly and nothing felt wrong with it after the treatment though. I pulled the negative off the battery overnight and reinstalled it the next day....check engine light was off and has stayed off for months now.

 

Your CEL could be as simple as a lean code due to pulling off the vacuum hose. If it's running better more than likely you didn't hurt any sensors. Go to autozone and have them pull the codes. Then ask them to clear them and wait to see if they come back. Good Luck!

 

Thanks for the tips. I will pull the batt cable, and see if that works, if it comes back, then I will go to Autozone and get codes.

 

it put my cel on too. I think it happens when u put too much in too fast. I had to buy a new a/f sensor

 

What I would do is just take the negative battery cable off, and see if the light comes back on, if it does, I would get the code pulled at autozone, It is okay to drive a couple of days with a bad o2, just dont do it for months like I did, It got so bad that I would have to floor the gas to get anywhere, and it would backfire like a machine-gun!! I replaced it and now it runs great!! The previous owner put a cheapie aftermarket one in there, and it only lasted about 10k miles, get factory if that is the problem!

 

That seafoam through the PCV hose trick does wonders. Granted I've never done it on a 4Runner, but I did do it on a beater 1996 Saturn SL2. The engine was so smoother after the Seafoam cleaning. I had a check engine light after as well, luckily on a Saturn you only have to disconnect the battery for 15 seconds to reset the PCM.

 

disconnected battery this morning and the CEL is gone. Happy motoring.

 

You'll have to drive it for a bit to see if it shows back up...