[Old Bear]

"see RPM rise when brake tapped & lockup disengages "
==
When in forth and TCC locked up. A rise in RPM when brake is tapped and (TCC) Torque Converter Clutch disengages is what we would expect for normal operation.

 

[eddsel]

"see RPM rise when brake tapped & lockup disengages "
==
When in forth and TCC locked up. A rise in RPM when brake is tapped and (TCC) Torque Converter Clutch disengages is what we would expect for normal operation.

I couldnt tell w/o tach. When locked up @ 45+ mph it felt like a slip or a cut in/out ? I replaced alot of gas/electrical parts on tbi.(see my other posts) Still acted up, unplug the tcc on side of trans & although rpm higher(normal) it didnt gimme that slip/cut. Is that how a bad tcc would act old bear? Feels like a wire ground out. Got my fingers crossed. Thanks

 

[Old Bear]

That is what I would expect with TCC wires unplugged at the transmission.
With no signal going in, it would not cause the TCC solenoid to engage.
Without being locked up at 1:1 by the TCC, there would be some fluid speed difference and the RPM would be a little higher on the tach. On mine it was about 200 RPM higher.
However, we are not yet sure if it is fluctuating signal coming in, or the solenoid inside the lower trans.

I think the trans shop that repaired mine turned the truck off.
I think Dave put power to the correct wire(s) to activate the solenoid to hear if it clicked on and held or if it bounced on and off. I don't remember if he heard it. I think with trans pan dropped he could hear it.

Hopefully someone will know if that is a useful additional test.

Also, how do the connections on the multi wire plug look where you disconnected from the trans?

 

[Old Bear]

In this thread, very knowledgable @MarvD mentions that the brake switch opens the circuit, so no power would be sent to the solenoid.
(1) tcc brake wiring? | El Camino Central Forum

 

[Old Bear]

@eddsel
I see you have updated your vehicle description to appear under your avatar.
That is great.

I am not as familiar with the last few years of fifth gen El Caminos, with the ECM (computer).
Let's ask @darbysan and others to chime in on whether the TCC Lockup signal on the '86 also goes through the ECM.

 

[Karadjgne]

I would think it would, since the carb didn't change, dizzy didn't change, tranny didn't change. All of it is ecm throughput and the NO relay would need a signal from somewhere to engage it at the correct time. The brake pedal would just break that signal, returning the relay to NO.

 

[eddsel]

That is what I would expect with TCC wires unplugged at the transmission.
With no signal going in, it would not cause the TCC solenoid to engage.
Without being locked up at 1:1 by the TCC, there would be some fluid speed difference and the RPM would be a little higher on the tach. On mine it was about 200 RPM higher.
However, we are not yet sure if it is fluctuating signal coming in, or the solenoid inside the lower trans.

I think the trans shop that repaired mine turned the truck off.
I think Dave put power to the correct wire(s) to activate the solenoid to hear if it clicked on and held or if it bounced on and off. I don't remember if he heard it. I think with trans pan dropped he could hear it.

Hopefully someone will know if that is a useful additional test.

Also, how do the connections on the multi wire plug look where you disconnected from the trans?

May be a bit ugly (that 3 wire plug) prongs are there, i will test w/ohm meter and may splice in new wire w/female bullet connectors to be 100% sure. Will do brake lite switch if necessary after test drive as when stopping (sometimes) car want to forge ahead. Gettin Close , sure have learned lots, whew ! Thank You 4 input. Wish i went this direction 1st.

 

[Caballero Joe]

I haven't quite figured out how to insert just one quote. @OldBear has a good point.
If your truck came from the factory with a lock-up torque converter it was originally controlled by the factory ECM.

 

[eddsel]

ecm is rebuild 5yrs ago. auto zone 150.00, no chk eng lites/codes. old shool me "ecm/electronic this" ! Thanx 4 input

 

[Old Bear]

The engine control module (ECM), also referred to as the engine control unit (ECU), is the engine's computer that controls engine performance. In some years with capable transmissions, it may have transmission control functions too.

 

[57 Handyman]

Thanks to all for contributing to this 2004r thread. I have two questions: First one is where or who sells aftermarket 2004r trans pans? Second question has to do with the best source for 2004r dust covers?

 

[Sledge Hammer]

Thanks to all for contributing to this 2004r thread. I have two questions: First one is where or who sells aftermarket 2004r trans pans? Second question has to do with the best source for 2004r dust covers?

Summit has an aluminum pan for the 2004r. It is pricey at around $375 as I recall. You can get dust covers there as well.

 

[Hat Trick]

How about this?
Tom

 

[Hat Trick]

My bad. Wrong pan.
Tom

 

[Old Bear]

California Performance Transmissions.

Normal TH-200 4R ALUMINUM FINNED Pan for Performance Transmissions (cpttransmission.com)
Deep TH-200 4R Deep Cast Aluminum Pan for Performance Transmissions (cpttransmission.com)

Note: Without gasket and filter. Not sure about drain plug.

Don't skip trans cooler.

 

[57 Handyman]

Thanks guys...for some reason, whenever I searched for those items, I never found any available. I made a drain plug on my stock trans pan out of an old temp gauge location and have JB Weld patched the tears in my stock dust cover.

Now, the last item in need of attention is TCC lockout. As I understand it, if the ECM is removed, the 2004r needs a 12v source via the 4-pin connector located on the driver's side of the transmission housing. For disengaging the lockout, my plan is to route key-on 12v power via the brake light switch then onto the transmission. So, the question is: is there a way to determine/identify which of the 4-pins is the correct position for input of the 12v source?

 

[Caballero Joe]

I installed the TCI kit that uses manifold vacuum

 

[Old Bear]

I really think you want the brake light switch to be dual and to break the signal for TCC lockup too,

 

[57 Handyman]

Cab Joe, can you share with me the position (according to this depiction of the connector below) where in the 4-pin connector does the 12v wire go?

clip
A B
C D

Old Bear, the brake light switch I have on my 87 EC has dual sets of connectors with pins/wires. This vehicle had cruise control which I removed; there are two sets of wires with connectors: front set has 3 wires (white, orange, lt blue) and the rear has 2 wires (gray and purple). My online research has stated I can use the rear set to control/disengage the torque converter lockout.

My main concern is asking Cab Joe which pin location is related to what detriment or damage may/will occur internally to the transmission (if any), if I send 12v power to the wrong pin/location? Is it as simple as NO lockout vs lockout? I surely do not want to cause any damage to the transmission circuitry or parts. Thank you in advance for your knowledge and assistance!

 

[Old Bear]

I have heard one good mechanic and a trans shop owner say:
"We can guess at the wires, yet on 40-60 year old trucks it is more about how the last person inside the trans set the wires up."