Engine light is showing code 23. Which manuel says is the manifold air temp sensor. Would this cause car to be hard to start when its cold? Any if it is the sensor any idea what that sensor would cost?? Any info would be appreciated thanks

 

Yes, a cooked MAT sensor will cause a hard start condition. It tells the ECM what temp the incoming air is (in theory). All it really winds up reading is the latent heat of the manifold. They are around $25 and I *think* that they can be changed on a stock TPI setup without removing the plenum. But i'm not 100% sure about that since it has been a while.

Also, make sure you get a MAT sensor and not a CTS. They look the same and have the same weather pack connection. The MAT sensor has a plastic head while the CTS has a metal head.

 

I replaced my mat sensor and I had to remove the plenum. It's really not difficult to remove actually, is just a matter of removing the intake runner bolts and loosening the bottom one. Should take you at least 3-4 hours to complete.

 

I stand corrected, as usual, lol. I couldn't remember if you can get at the sensor without pulling the plenum.

 

With the Superram,I just bypassed it with a resistor.One for the cold and one for the summer.

 

If you pulled the dist, there might be enough room to get at it. Sure you would have to set the timing again but it should be easier than pulling the plenum and dealing with gaskets ect.

 

lol nope

The runner gaskets seldom break..Easier to pull the plenum if you have the stock TPI

 

Wow boys, hold on.

Why not leave it where it is and install a new one in the air intake tract somewhere? I had one for the old TPI motor before the MAF in the air box lid. Just extend the wiring and presto, no more incorrect readings due to plenumn heat soak. Should make more power as well, as the computer won't lean the mixture due to a false hot air intake readings.

Later year cars and vettes have this from factoy I believe.

You can still see my old sensor in the air lid in the photo.

 

Yeah, I think moving it would be easiest. Disturb those old gaskets and things could snowball on you.

I was at a dealership today needing some ltd. slip additive and inquired about the TPI gaskets and a bunch others. The TPI gaskets have been discontinued. Bastards!

Just head gaskets are $56! The 3 little TB gaskets are $26. Hwy robbery I tell ya.

 

You can get the Runner gaskets from Felpro. I bought the entire kit when I rebuilt my 89 L98.

 

MAT relocation does sweet-****-all without corresponding PROM changes.

 

Not sure about the PROM changes...could be.
Still easier to relocate it.

 

It sure would be.

Can you unplug the connector with the plenum on? My car lasted about 2 months before I blew it up and removed the factory TPI gear. I never had much of a chance to fiddle with it.

 

not without breaking the connector.

Ill just splice and put a resistor on it for a quick fix (or just to be check if that is the problem)