Car Fart?

[joetrainer31]

Yes, the title is juvenile, but the concern is not. Upon starting the car anew for the day (i.e. while its still cold) I notice that it seems to exhibit symptoms of being overly rich. In other words, it seems to bog when pulling out of the parking lot, the pedal seems mushy, and every couple of mornings it will backfire (fart) through the cats.

Just throwing this out there, but I dont know if it matters -the previous owner put a 160 stat in the car. Also, I scanned for codes concerning this concern, but the scanner retrieved no fart inducing codes. Master techs, what's the good word?

 

[toyman]

Dirty or failing MAF, so clean and/or replace . Stock T-stat is 195*. Address these two items first.

 

[joetrainer31]

Dirty or failing MAF, so clean and/or replace . Stock T-stat is 195*. Address these two items first.

Hello toyman. Yes, I certainly agree with your advice. I cleaned the MAF w/the proper cleaner when I first received the car. I took the housing apart and sprayed the cleaned directly on the wires, but I did not take the sensor out of the housing. Should I take the sensor all the way out and clean it again?

The T-stat is bugging me for sure. I won't be able to change it until my semester is over (3 weeks). When I change it I plan on using a balanced T-stat, but I am undecided on 180 vs 195. The Rad is tight, the fan works perfect, and I have under drives, GT40 heads, SVO intake. Would you mind telling me which you suggest and maybe why you suggest it? I would greatly appreciate your feedback.

Thank you for your time!

 

[JordanB21]

I would suggest a 180 degree t-stat, especially if you live in a hot area. 160 is typically way too cold.

You should try cleaning the MAF outside of the housing, via removing to the two tamper proof star screws. I used 3 or 4 q-tips and brake cleaner, course I'm sure you can figure out what to do. They aren't nessarily fragile, but you should treat the wires as such when rubbing them. Leave no residue, and no cotton swob pieces behind.

If you do pull it out and visually inspect it you should see a fine coat of black on one side, the direction towards the intake inlet.

 

[joetrainer31]

I would suggest a 180 degree t-stat, especially if you live in a hot area. 160 is typically way too cold.

You should try cleaning the MAF outside of the housing, via removing to the two tamper proof star screws. I used 3 or 4 q-tips and brake cleaner, course I'm sure you can figure out what to do. They aren't nessarily fragile, but you should treat the wires as such when rubbing them. Leave no residue, and no cotton swob pieces behind.

If you do pull it out and visually inspect it you should see a fine coat of black on one side, the direction towards the intake inlet.

Agreed, 160 is too low. I'll put a balanced 180 in it. I'll also pull the MAF sensor out and clean it. I have specific MAF sensor cleaner for it.

 

[toyman]

Just so everybody is clear, the T-stat rating only establishes the minimum operating temperature. A higher rated one allows the engine to warm up to it's specified operating temperature quicker. This is important because during the warm up period the computer is adding extra fuel (using a fuel enrichment vs temperature table) and the O2 sensors are in open loop so as to not send a conflicting fuel load signal.

 

[joetrainer31]

Just so everybody is clear, the T-stat rating only establishes the minimum operating temperature. A higher rated one allows the engine to warm up to it's specified operating temperature quicker. This is important because during the warm up period the computer is adding extra fuel (using a fuel enrichment vs temperature table) and the O2 sensors are in open loop so as to not send a conflicting fuel load signal.

Thank you for the explanation. It is very helpful. So, 180 or 195 balanced T-stat. I will be running no power adders. Only GT40 heads and intake w/under drives & gears.

 

[joetrainer31]

Just so everybody is clear, the T-stat rating only establishes the minimum operating temperature. A higher rated one allows the engine to warm up to it's specified operating temperature quicker. This is important because during the warm up period the computer is adding extra fuel (using a fuel enrichment vs temperature table) and the O2 sensors are in open loop so as to not send a conflicting fuel load signal.

So I figured out what the problem was. I stopped taking the previous owner's word that the engine timing was at stock and checked it myself. I knew it wasn't advanced because I was running 87 w/o pinging. You guys will never guess what the timing was; it was about 22 degrees retarded.

No wonder the car bogged upon first start up, had a mushy pedal, and seemed to lack power. I was thinking: I know the 94-95s don't pull like the fox bodies, but this is ridiculous. I was scratching my head because of all the mods this car has, and yet it was a pig. 22 degrees was why! Thank The Lord that was all it was.

 

[toyman]

I'm not so certain that the car would run with 22* retarded. I would carefully inspect the balancer. If you see any wobble or can feel or see any rubber protruding on the engine side you can assume the outer ring has slipped and any timing being read is bogus. If it is bad you need to replace it or you run the risk of serious engine internal damage.

 

[joetrainer31]

I'm not so certain that the car would run with 22* retarded. I would carefully inspect the balancer. If you see any wobble or can feel or see any rubber protruding on the engine side you can assume the outer ring has slipped and any timing being read is bogus. If it is bad you need to replace it or you run the risk of serious engine internal damage.

I'll give it a visual again. When I was under the car today I didn't see any rubber protruding, and when I was checking the timing I didn't notice a wobble. Maybe I need a 2nd opinion look-see.

I do know that when I 1st shined the timing light I couldn't see any numbers or colored markings. I was a bit confused. So, I had a friend keep his eye on the pointer as I turned the distributor clockwise. Well, I kept turning and turning and turning, and bingo -he finally saw the 2 white and red markings. It was WAY retarded. I suspect somebody tried to set the timing w/the spout connector plugged in, who knows. The car is like a totally different vehicle now. It actually accellerates.

 

[RIO5.0]

FWIW... I run a 195 in my 331. Lower units never let the thing get hot, didnt feel comfortable with that. I ran a balanced 180 for a season or two. I wanna see some heat in there.

 

[madspeed]

sorry to bust in, but is there a recomended t stat brand or part number? Its been so long since ive changed one that im thinking mine is too low temp and want to get a good stock relacement

 

[joetrainer31]

sorry to bust in, but is there a recomended t stat brand or part number? Its been so long since ive changed one that im thinking mine is too low temp and want to get a good stock relacement

Not sure about the brands but I'd like to get a balanced 192 or 195 if possible.