1984 Trans Am Cruise Control
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Car: K-1 Evoluzione (85 Camaro)
Engine: 5.7L
Transmission: TH700R4
Axle/Gears: stock
1984 Trans Am Cruise Control
Hey 3rd Gen community. Need your help on a 1984 Trans Am question. Does this car use a vehicle speed sensor to control the cruise control? Car is a carbed motor. If it does use a VSS, where is it located? Does it also need a VSS buffer module? What about cabling from the transmission to the VSS (if it has one), and then on to the speedometer and cruise control? How does that work?
Your help is greatly appreciated!
Your help is greatly appreciated!
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Re: 1984 Trans Am Cruise Control
Hey 3rd Gen community. Need your help on a 1984 Trans Am question. Does this car use a vehicle speed sensor to control the cruise control? Car is a carbed motor. If it does use a VSS, where is it located? Does it also need a VSS buffer module? What about cabling from the transmission to the VSS (if it has one), and then on to the speedometer and cruise control? How does that work?
Your help is greatly appreciated!
Your help is greatly appreciated!
When you activate the cruise, the cruise servo next to the radiator uses the vacuum it senses in the system to sets to the speed and holds the throttle steady via the cable that goes up to the throttle bracket.
I am 90% positive that it uses only the vacuum pressure and not a VSS to sense what speed to hold it at so if you have a vaccum leak, this will cause the system to "hunt" for the correct speed. It will also cause it to surge a bit going up and down hills as the engine works harder/easier in those situations.
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Re: 1984 Trans Am Cruise Control
Hey 3rd Gen community. Need your help on a 1984 Trans Am question. Does this car use a vehicle speed sensor to control the cruise control? Car is a carbed motor. If it does use a VSS, where is it located? Does it also need a VSS buffer module? What about cabling from the transmission to the VSS (if it has one), and then on to the speedometer and cruise control? How does that work?
Your help is greatly appreciated!
Your help is greatly appreciated!
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Car: 85 SC, 86 Berlinetta
Engine: V6, V8
Transmission: 700r4, 700r4
Re: 1984 Trans Am Cruise Control
I was going to add cruise to one of my Camaros a while back.
There is a cruise control module near the ECU under the dash.
The VSS sensor should be connected to the (mechanical) speedometer with red, black(?), & green wires that lead to a yellow box that then leads to the connection out of the cluster. From what I recall, the ECU, CC module, brake switch and VSS are interconnected with the rest of the CC system.
I suspect that you Firebird is similar.
There is a cruise control module near the ECU under the dash.
The VSS sensor should be connected to the (mechanical) speedometer with red, black(?), & green wires that lead to a yellow box that then leads to the connection out of the cluster. From what I recall, the ECU, CC module, brake switch and VSS are interconnected with the rest of the CC system.
I suspect that you Firebird is similar.
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Car: K-1 Evoluzione (85 Camaro)
Engine: 5.7L
Transmission: TH700R4
Axle/Gears: stock
Re: 1984 Trans Am Cruise Control
When I looked at the wiring diagrams, I see there is a signal wire from the ECU in the circuit to the cruise harness. I just pulled the dash harness out of a 85 Firebird and it looks almost identical to the 84 T/A circuit. So yes, there is some sort of interconnection between the ECU, the cruise, and brake. But, I didn't see anything that I could positively identify as cruise module. Like OZZ1967 said, the speedo cable runs straight from the cluster to the trans. There is an electrical connection from the trans to the ECU that I assume includes the TCC and OD (top gear) connections.
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Car: 85 SC, 86 Berlinetta
Engine: V6, V8
Transmission: 700r4, 700r4
Re: 1984 Trans Am Cruise Control
Ok, I located and old post I made that includes images of the system. Some wiring goes to the main harness and were marked as open. Example:
Original post:
https://www.thirdgen.org/forums/post...97-post21.html
Also an Ebay add for the cruise control module for identification purposes.
http://www.ebay.com/itm/1986-PONTIAC...-/300786745724
Here's a link of the VSS sensor that should be on the back of any mechanical speedometer cluster. They call it a filter but the sensor is the black thing on the end.
http://www.ebay.com/itm/85-1985-CAMA...-/220355508401
Original post:
https://www.thirdgen.org/forums/post...97-post21.html
Also an Ebay add for the cruise control module for identification purposes.
http://www.ebay.com/itm/1986-PONTIAC...-/300786745724
Here's a link of the VSS sensor that should be on the back of any mechanical speedometer cluster. They call it a filter but the sensor is the black thing on the end.
http://www.ebay.com/itm/85-1985-CAMA...-/220355508401
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Car: K-1 Evoluzione (85 Camaro)
Engine: 5.7L
Transmission: TH700R4
Axle/Gears: stock
Re: 1984 Trans Am Cruise Control
Looks like pretty much everything, except that box in the center, left in the picture. what do you call that module? BTW, thanks a TON for posting that picture!!
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Car: K-1 Evoluzione (85 Camaro)
Engine: 5.7L
Transmission: TH700R4
Axle/Gears: stock
Re: 1984 Trans Am Cruise Control
found it right where you said. GM p/n 25031953 on it. Found one listed on eBay too that pretty much confirms what I'm looking for to complete the system.
By the way, I posted this in response to a customer's question. He converted a 1984 T/A from left-hand to right-hand drive (in Australia) and wants to make his cruise control fully functional again. He did an awesome job crafting the conversion.
Thanks very, very much for all your help and input on this.
By the way, I posted this in response to a customer's question. He converted a 1984 T/A from left-hand to right-hand drive (in Australia) and wants to make his cruise control fully functional again. He did an awesome job crafting the conversion.
Thanks very, very much for all your help and input on this.
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Car: 85 SC, 86 Berlinetta
Engine: V6, V8
Transmission: 700r4, 700r4
Re: 1984 Trans Am Cruise Control
You are very much welcome! I had to learn the hard way when I bought one online and found out that I only received half of what was needed.
That sounds like a cool project and possibly a bit frustrating as well. If he posted the project online please send me a link, I'd like to see it.
That sounds like a cool project and possibly a bit frustrating as well. If he posted the project online please send me a link, I'd like to see it.
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Car: K-1 Evoluzione (85 Camaro)
Engine: 5.7L
Transmission: TH700R4
Axle/Gears: stock
Re: 1984 Trans Am Cruise Control
I've let him know his "fan club" is asking for pictures. He emailed a couple to me. It was a pretty slick conversion. Looked almost factory-installed. Quite an accomplishment. Aussies! Go figure.
#16
Re: 1984 Trans Am Cruise Control
Guys, I'm in Australia which means we are a Right Hand Drive Country. This means that unless are vehicle is a "classic" i.e. 30 years old or more, it MUST by law be converted to Right Hand Drive before you can drive it on our streets. Even if the car is 30 y.o.+ it's really not all that safe to drive around by yourself especially at intersection when turning right because from the L/H seat you simply cannot see oncoming traffic. Not to mention you need all the suspension adjusted so that it sits flat on the road to allow for the natural road falloff for rain. Of course, you also need to replace the headlamps so that they don't blind oncoming drivers at night. All these little things. Here are some pics of both my 67 Mustang conversion and my 84 TransAm conversion. Yes, each is difficult for various reasons but the plastics in the TransAm dash are very difficult considering the way the instrument cluster butts up against the connectors so if you plastic engineering is just a little bit out, the electricals won't line up and either not work, or worse, they can short out really easily and burn up wires and/or the printed circuit board (which need to be cut in half and re-joined). There is none of this with the Mustang conversions.
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Re: 1984 Trans Am Cruise Control
Guys, I'm in Australia which means we are a Right Hand Drive Country. This means that unless are vehicle is a "classic" i.e. 30 years old or more, it MUST by law be converted to Right Hand Drive before you can drive it on our streets. Even if the car is 30 y.o.+ it's really not all that safe to drive around by yourself especially at intersection when turning right because from the L/H seat you simply cannot see oncoming traffic. Not to mention you need all the suspension adjusted so that it sits flat on the road to allow for the natural road falloff for rain. Of course, you also need to replace the headlamps so that they don't blind oncoming drivers at night. All these little things. Here are some pics of both my 67 Mustang conversion and my 84 TransAm conversion. Yes, each is difficult for various reasons but the plastics in the TransAm dash are very difficult considering the way the instrument cluster butts up against the connectors so if you plastic engineering is just a little bit out, the electricals won't line up and either not work, or worse, they can short out really easily and burn up wires and/or the printed circuit board (which need to be cut in half and re-joined). There is none of this with the Mustang conversions.
84 is 30 years old starting this fall depending on when yours was built. Don't convert it.
There are guys driving Firebirds and Fiero's all over England without converting them to RHD, just adjusting the headlamps.
I drove mine for 3 years when I was stationed there with the US military and never really had any problems, I just had to make sure I was very clear when passing or turning. Yes, it's difficult, but not hard to overcome.
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Car: 85 SC, 86 Berlinetta
Engine: V6, V8
Transmission: 700r4, 700r4
Re: 1984 Trans Am Cruise Control
Wow! That is truly amazing. I'm somewhat familiar with how close things are behind the dash as well as the connectors on the cluster, so I can appreciate what you're saying about that. I imagine that reconnecting the electrical was a bit challenging after cutting that cluster in half. That's not mentioning all of the mechanical and other electrical work. You've done a really nice job on both the Trans Am and the Mustang. Thank you for coming here and posting the images.
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