3.492rs

Hey guys I recently swapped my topend from a tpi maf unit over to a holley 4150, and Im trying to get the tpi ecm to control the primary fan and torque convertor lockup, but the convertor won't lockup and the primary fan that the ecm controls does not kick on.

I DID NOT CUT any of the factory harness wires or disconnected any relays just moved what i wasn't using out of the way.

the sensors I kept on the engine and transmission is the stock 3 wire oil pressure sensor for my dash oil gauge and to kick on the tpi fuel pump (works fine),
the secondary fan switch in the pass side cylinder head (works fine),
the coolant temp sensor for my dash temp gauge also (works fine),
the coolant temp sensor for the ecm in the intake manifold,
and the wires going to the 700r4 for the torque convertor and the speedo cable.

All gauges in the dash cluster work. The tpi ecm still turns on the fuel pump for the first 2 seconds of key on and I have a check engine light from the gauge cluster, so the ecm is getting power, but I don't see why it can't operate the tcc lockup and primary fan.

Everything operated fine when I had the hsr still on it.

Let me know if theres a problem or if I have to run a stand alone system? but I would like to have the tpi ecm doing its job.

Any help would be appreciated,
thanks.

five7kid

iTrader: (14)

The ECM is doing all you can expect of it with the input it now has.

It needs the engine RPM ("cam sensor" in the vernacular), throttle position, and manifold vacuum inputs in order to have what it needs to command the torque converter lockup.

3.492rs

Ok what about the primary fan, what does the ecm need for the fan to function properly?

soarestransam

U could hot wire the lock up thats what alot of old hot rodders do when they use a 700r4 instead of the th350 or 400 I believe summit sells a kit oh an for the fans there is a fan switch usually in the passenger side clyinder head check to see if that is good also u could check the fan relay might of blown

vetteoz

iTrader: (13)

In theory a functioning CTS which you say is still wired up
I recall when I had the same setup; I could not get the ECM to run the fan
Didn't really study it ; instead I ran the fan from a seperate temp switch in head

TCC you can;
wire it internally so it lockups anytime it goes into 4th ( easiest ; only a 12V wire required to trans )
use a external switch to manually engage lockup ; have to remember to turn it off when coming to a stop
or a self controlling vac system
https://www.thirdgen.org/forums/carb...c-control.html

Camaro305SB

If the factory wiring is still in tact (or partially) the brake pedal grounds the TCC so it shouldn't be an issue. The only issue would be the converter locking to soon which would make the car feel like a dog.

3.492rs

Well thanks for your help guys, I guess theres no reason to leave the cts in there and the ecm powered.

Apeiron

The brake pedal switch supplies +12v to the TCC.

Camaro305SB

Oh so its on the power side. Ok thanks I thought it grounded it.

RRUHL

have a serious torque convertor issue motor runs great put it in gear and instantly kills I adjusted the tv "way off" still no luck then out of curiosity I unpluged the sensor towards the front on the drivers side and the issue was gone shifted into gear without shuting off for the first time in 3 weeks. is this a torque convertor issue? or any ideas/ info on what that could mean??? thanks