OH how I love emmissions stuff!

[Veepster]

hey guys!

I am finally figuring out my vacuum routing nightmares...It appears that my 78 Chero does not have the required Transmission Controlled Spark Solenoid and the Coolant Temp Override Switch.....The CTO is a sensor that is mounted into the T-stat housing that has 3 vacuum ports coming out of it.....the vacuum advance of the dist connects to this and does not allow the vacuum advance to function until the motor warms up a bit

the TCS is a solenoid that mounts on the right rear of the motor and connects to the trans...

there lies my problem! all the docs I have state that a wire is supposed to come from the trans and connect to this solenoid...I can't find any wire on the trans that should go to the TCS..does anyone know where it is? BTW: it is an auto trans...

also I haven't checked the prices for these parts new, but does anyone have them sitting around they want to part with?

thanks!

Peace...................BartG

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Veepster:
I am finally figuring out my vacuum routing nightmares...It appears that my 78 Chero does not have the required Transmission Controlled Spark Solenoid and the Coolant Temp Override Switch.....The CTO is a sensor that is mounted into the T-stat housing that has 3 vacuum ports coming out of it.....the vacuum advance of the dist connects to this and does not allow the vacuum advance to function until the motor warms up a bit

the TCS is a solenoid that mounts on the right rear of the motor and connects to the trans...

there lies my problem! all the docs I have state that a wire is supposed to come from the trans and connect to this solenoid...I can't find any wire on the trans that should go to the TCS..does anyone know where it is? BTW: it is an auto trans...

also I haven't checked the prices for these parts new, but does anyone have them sitting around they want to part with?<HR></BLOCKQUOTE>

The TCS uses a wire coming from the transmission (uses the same plug as the kickdown, but with two spades rather than one). If your truck was not originally built for california, however, your transmission may not have provision for providing the TCS solenoid a signal when it is in high-gear. Check that the plug on your transmission has two spades, and that the plug coming off of it has two wires. One will go to your kickdown switch on the accelerator, and the other would go up to your TCS solenoid.

I have no idea where you'd get a new TCS solenoid, or how you'd retrofit a TH400 to provide you with that signal if it isn't already equipped to do so. You could always run a dummy-wire, if they aren't going to check for the proper operation of that switch.

As for the CTO, it's the standard Yellow 155º (or 160º) one that AMC used for ages. Look for the interchange chart on these at:

http://home.off-road.com/~wagoneer/tech/cto.html

Look at the second row, for the parts that cross to the AMC J3235917/3229450/3216448 part #'s.

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Bob Barry
<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]
http://studentweb.providence.edu/~rbarry/wheels/

[Skye]

Um.... i could have told you that.....

Geez you guys! Why dont I have anyone of you guys who knows their stuff around here!!!! SC sux in the automotive area.

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83 Wagoneer.... um... thats all:)

[Veepster]

thanks Bob!

It IS a California vehicle...but after 22 years who knows where the trans came from! or the motor! so is that the plug on the drivers side towards the front of the trans? If so i will check tonight to see if it has 2 spades...

TCS solenoid......sounds like a dealer part to me.......ching ching!

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Veepster:
It IS a California vehicle...but after 22 years who knows where the trans came from! or the motor! so is that the plug on the drivers side towards the front of the trans? If so i will check tonight to see if it has 2 spades...<HR></BLOCKQUOTE>

Yes, it is that connector. GM used a similar system on some of its cars in the early-70's, so there already may be provisions in a transmission, even if it is a replacement.

<BLOCKQUOTE>quote:</font><HR>TCS solenoid......sounds like a dealer part to me.......ching ching!<HR></BLOCKQUOTE>

If you don't actually need it to be functional, you could even create a dummy switch or adapt a TCS solenoid from another vehicle (will the inspector recognize if the TCS on there is not an original Jeep part?). Heck, a vacuum delay valve with an electrical connector glued on it and some wires running off into the wiring loop would probably serve the purpose... http://www.cs.colostate.edu/~zeimet/ubb/wink.gif

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Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/

[Veepster]

thanks Bob..

I did some crawling around last night and found the trans sensor to be one spade.....the connector has 2 holes for spades even though only one is used....

I also did some reading in my TSM and it stated that on the 78 Auto w/ 360 the sensor would be inline of the speedo cable mounted behind the dash.....I checked there and found absolutely nothing....so I don't think it came with one....I can see someone tearing off the smog equipment but I can't see someone removing the dash to remove the sensor....

and I also read that the 304 did not come with the TCS......even though my VIN says mine was a 360 I am guessing maybe mine did not coem with one....I know it was a California vehicle and that it was also a high altitude vehicle(it has that altitude compensator on the carb)....

so I think I am going to approach it as a 304 and put all the smog stuff for a 304(same as a 360 w/o the TCS).......I am just trying to be as authentic as possible, luckily for me I know the guys at the SMOG place and they will let me slide on the visual stuff...

thanks again Bob!

Peace.......................BartG