joshwiles

Hey guys, I swapped from CFI to TBI on my 84 vette which is suppose to be a direct swap. I used my CFI injectors and IAC. I now have no TCC lock-up. Also, my performance seems to be poor. Any thoughts? Thanks

C409

............ Did you install / adjust the TV cable for the transmission ?? ..........

383vett

You need to change fuel pumps. How did you use your crossfire injectors on a tuned port setup? Did you change ecm's?

joshwiles

Yes, I hooked up TV and adjusted. Shifts are correct just no lockup. And TBI (throttle body injection) not TPI (tuned port injection)

-js-

TCC controlled by the computer?
So look at the sensors that are used to calculate the lockup signal.
Wish I could be more specific but I have no 84 vette xfire experience.
I would think the TPS & MAF or MAP for load calcs and throttle movement would be used maybe others like temp too.
Hopefully someone can chime in with the details on how it is done.

joshwiles

TCC is controlled by the computer which takes speed, MAP, A/F Ratio, and RPMs into account I believe. But all that should be working. Basically I just removed one of the TBs. The new TB has 1 instead of 2 IACs, but other than that, all the wiring in hooked up. Unless the TPS is bad?? Multimeter test seemed to think it was fine though.

vetteoz

Grounding pin F on the ALDL should lockup convertor to confirm wiring to TCC is correct and working
If convertor does not lockup then you have a problem on the power supply side ( not ECM related ), bad brake switch /bad wiring / connection /faulty solenoid etc

383vett

Sorry Josh, I'm a little slow and have trouble comprehending what your setup is. The crossfire has two throttlebodies. Now you switched over to one throttlebody? Willie

-js-

383 what i read into it is he took off the crossfire intake system and replaced it with a TBI system.
He also is saying performance is poor.
So this could be any number of things.
Vetteoz suggestion to ground it at the aldl is good test to narrow things down.
Can Josh scan on the ALDL connector on his 84 ?

383vett

Hey, I told you I was slow.

pcolt94

Is it possible one of the switches that is incorporated with the brake or clutch cruise portion is not closing or making good contact. I know that on my 94 if the switch body is not properly adjusted it will not let the TCC or cruise engage.

62panshovel

As suggested previously ground pin F of the ALDL with the KOEO and on mine you can hear the solenoid engage. You can also drive with a test light plugged in to pin F and when the computer calls for lock up the light will go out as the ECM completes the circuit by providing a ground when conditions are met. KOEO with a test light in pin F should light. If no light then power is not getting back to the ECM. Usually brake switch. Depress brake should kill the test light. Proves correct actuation of brake switch. Must be above 42mph and 135degree and steady TPS signal for ECM to close the circuit. All this is in the FSM chart c-8a ...

joshwiles

Sorry about the delay. I have switched from two single barrel TB's to one double barrel TB. Same injectors, same wiring minus an IAC. As for the ALDL, is pin F in the top left? And should I attempt manually engage it first? Or do the test light thing? One more question. If the timing/distributor/ignition had a problem, could that cause the TC to stay unlocked? it's just a thought.

62panshovel

Pin F. Top left. KOEO = key on engine off. I would first place the test light into pin F with KOEO and make sure it is lit. Then press brake and see it go out. These prove circuit function. You can then ground Pin F and listen to hear the solenoid engage. I can hear mine click. If yes on these then I would drive the car with the test light in Pin F and see if the light goes out when conditions for lock up are met (speed, temp and consistent throttle). This would prove ECM function.