4runner running rough

[jzilla]

I have a 93 4runner v6 It runs rough on occasion. replaced oxygen sensor and fuel filter. its improved but still rough half the time even when the engine is hot. Sometimes there is an odd burning smell.
Toyota could not find anything wrong.
Any ideas? Anyone else have smiliar problem like this?
Someone said catylitic converter?
thanks,
john

 

[calamaridog]

I have a 93 4runner v6 It runs rough on occasion. replaced oxygen sensor and fuel filter. its improved but still rough half the time even when the engine is hot. Sometimes there is an odd burning smell.
Toyota could not find anything wrong.
Any ideas? Anyone else have smiliar problem like this?
Someone said catylitic converter?
thanks,
john

John,

Has your motor ever had a motor treatment such as SEAFOAM? Carbon build-up can and will cause the motor to run poorly. I've used this stuff successfully on several Toyota motors and recommend it as a regular maintenance item.

Read about it at http://www.seafoamsales.com/motorTuneUpTechGas.htm

There was a huge thread about SEAFOAM at Yotatech a few months back. Do a search if you have any doubts.

Regards, Bryan

 

[jzilla]

thanks, by the way it has 140 000 km on it.

 

[calamaridog]

I would definitely look into it and you should be able to find SEAFOAM engine treatment up North. Whatever you do, read the instructions and follow them.

 

[keisur]

have you cleaned your MAF sensor? it may have some build up. might not cause rough running mut it'll make it sluggish. Also check your fuel filter if you haven't lately. mine runs rough when I need to replace it.

I used seafoam about a year ago when that thread started and it worked well.

 

[robinhood4x4]

2nd gens don't have a MAF like the 3rd gens, they have a AFM which is a vane type of flow meter. It's basically a flap that opens depending on the air flow.

Sometimes the flap sticks if it's dirty. I'm not sure if you have to take it apart to clean it, but if you do, be careful not to rip out the delicate wires inside cover. It's very easy to do and a new AFM costs about $700.

 

[jzilla]

Replaced fuel filter recently, what does AFM stand for?
Where is it?
thanks,
john

 

[calamaridog]

2nd gens don't have a MAF like the 3rd gens, they have a AFM which is a vane type of flow meter. It's basically a flap that opens depending on the air flow.

Sometimes the flap sticks if it's dirty. I'm not sure if you have to take it apart to clean it, but if you do, be careful not to rip out the delicate wires inside cover. It's very easy to do and a new AFM costs about $700.

I know tons of people who clean the MAF with electrical contact cleaner, which is not harsh. I'm not remembering what the AFM looks like so I'm not sure...

 

[keisur]

I know tons of people who clean the MAF with electrical contact cleaner, which is not harsh..

that;s the way I was talking about cleaning it.

 

[lc1996]

John, has the head gasket recall been done on it?

Carl

 

[jzilla]

Yes the head gasket recall has been done.
What is the MAF though? t
thanks
john

 

[lc1996]

Yes the head gasket recall has been done.
What is the MAF though? t
thanks
john

Mass Air Flow meter, which robinhood had mentioned that didn't come out until the 3rd gens.

Carl

 

[robinhood4x4]

MAF and AFM do the same thing, but they do it differently.

A MAF uses a thin wire which is placed in the flow of the air. Electricity is sent through the wire which elevates the temperature of the wire and the temperature is monitored. The more air that passes over the wire the more electricity is needed to keep the temperature up. The computer figures out how much electricity is needed to keep the wire at a certain temp and therefore knows how much air is going into the engine. This is otherwise known as a "hot wire anemometer".

A AFM (Air Flow Meter) uses a flap to monitor air flow. The more air passing over the flap, the more the flap opens. The computer knows how much the flap is open and therefore knows how much air is going into the engine.

Lots of people spray electrical contact cleaner on the MAF wire, but this is different from the delicate AFM wires I was talking about earlier. The delicate wires I'm talking about are just normal wires that are inside the AFM, but lots of people who take the AFM apart seem to pull the wires apart and I hear it's a pain in the butt to solder back together (or impossible?). Again, I've never cleaned my AFM, so I don't know if you need to take it apart to clean it.

The AFM (or MAF) is the box right after the air filter.