The Mustang Forum for Track & Racing Enthusiasts

Taking your Mustang to an open track/HPDE event for the first time? Do you race competitively? This forum is for you! Log in to remove most ads.

  • Welcome to the Ford Mustang forum built for owners of the Mustang GT350, BOSS 302, GT500, and all other S550, S197, SN95, Fox Body and older Mustangs set up for open track days, road racing, and/or autocross. Join our forum, interact with others, share your build, and help us strengthen this community!
BackInBlack 1.jpg

S197 BackInBlack Build Thread Profile - S197 Mustangs

Chassis Swapped Boss 302

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

I'm now wondering if the clock spring/cluster is somehow tied to the BCM?
I'm to the point where I put power to everything today and tried to crank the motor. No luck. I got what looked like a security lock out.
I have swapped in the motor/transmission combo, pedal assy, anti-lock module, BCM, and PCM.
The vehicle still has its original clock spring/cluster/keys.
No crank, just lights on the cluster, one of which was the "lock"symbol.
I did hook up the neutral safety/pedal assy harness to the connector above the pedal area.
Any thoughts?
@Stangra is right. You gotta use FORScan to sync everything together. Whichever parts did not come with the pallet need to be setup on the pallet's PCM. Before you start, make sure you have your two keys that fit the ignition and that they have unique transponders.

Here's a video that shows how to do it. In this video, the guy is doing a '13-14 cluster swap onto a '11-12 car, but the procedure will be the same. There may be more depending on what other modules you need to add.
When you're done, you should check the other modules on the car against the AsBuilt configuration for the VIN of a car that matches the setup you're using. If you have the VIN of your donor, that should do it (assuming it has the same trim level). If not, I'd just go onto Copart and look for a car that matches your build, and use it's VIN to get the codes. If I understand right, your donor was a manual, so hopefully you won't need to flash the PCM right away. But if/when you need to flash it, if you don't have the VIN, you can use the VIN you grab from Copart (or somewhere like that) to program your PCM as well.
 
Last edited:
Here's the picture of the previous set of plugs. As you can see, the 3rd one from the left has crap all over internal insulator. (I don't know what order the plugs are in.)
plugs.jpg
This has me thinking rocker arms, valve seals, piston rings, or just the cylinder scoring... Whatever it is, it seems to be affecting some cylinders more than others, which fits with what I've found so far. I'll check out the body harness connector next weekend but I don't expect to find anything.

Gonna stew on this for a while and come up with a new game plan. Got some other minor things to fix in the meantime.
 
@Stangra is right. You gotta use FORScan to sync everything together. Whichever parts did not come with the pallet need to be setup on the pallet's PCM. Before you start, make sure you have your two keys that fit the ignition and that they have unique transponders.

Here's a video that shows how to do it. In this video, the guy is doing a '13-14 cluster swap onto a '11-12 car, but the procedure will be the same. There may be more depending on what other modules you need to add.
When you're done, you should check the other modules on the car against the AsBuilt configuration for the VIN of a car that matches the setup you're using. If you have the VIN of your donor, that should do it (assuming it has the same trim level). If not, I'd just go onto Copart and look for a car that matches your build, and use it's VIN to get the codes. If I understand right, your donor was a manual, so hopefully you won't need to flash the PCM right away. But if/when you need to flash it, if you don't have the VIN, you can use the VIN you grab from Copart (or somewhere like that) to program your PCM as well.
Everything I'm swapping from the pallet came from the same vehicle. It was running on the pallet in my garage. I bought it from Cleveland Performance.
I should've just swapped all the components over like I planned. I even have a complete body harness, but so far I've just done the pin swap in the ECU plug.
Im headed out of town for a week, I'll swap in the last items next weekend and give her another try.
 
Everything I'm swapping from the pallet came from the same vehicle. It was running on the pallet in my garage. I bought it from Cleveland Performance.
I should've just swapped all the components over like I planned. I even have a complete body harness, but so far I've just done the pin swap in the ECU plug.
Im headed out of town for a week, I'll swap in the last items next weekend and give her another try.
Just so you know, I don't think you need to do any of that. I think the problem you're facing currently is that you need to initialize the cluster. But if you want to skip that, it's easy enough to use the pallet's cluster (you will still need to program your keys). The clocksprings don't have any computer components that need programming. Either one of them will work.
 
Why would I need to program the key if the one that came with the pallet starts the pallet?
If the key, transponder, and cluster all get swapped then it should fire, right? Isn't the transponder in the clock spring?
 
Why would I need to program the key if the one that came with the pallet starts the pallet?
If the key, transponder, and cluster all get swapped then it should fire, right? Isn't the transponder in the clock spring?
Because the ignition lock cylinder that came with the pallet isn't in your car (unless you swapped it). The key has to fit the lock, nothing more than that. If you want to use the pallet's keys, you can swap the lock cylinders but there's no need to do that unless you prefer to do the lock cylinder swap instead of programming the keys. My understanding is that the transceiver rings have nothing unique about them so there's no need to swap those.

The transponder is in the KEY

If you want to duplicate the pallet setup, all you need is the cluster and the ignition cylinder.
 
Last edited:
A new theory: Cracked valve cover?

Been talking a lot with AI about my situation, and the AIs seem certain that I have an unmetered air leak because of the fact that my fuel trims go back to normal on the road. It seems to make sense to me. I went looking for more possibilities for an unmetered air leak and came up with the valve cover. Apparently this fits the symptoms quite nicely -- and is something I've seen some of you guys grapple with before. I don't see any visible cracks so first I'm gonna go back and do what Lund suggested: I'll try running PCV breathers. If this fixes my trims, then it's GT500 valve cover time.
 
I found something guys...
20260826_213806(1).jpg20260826_214246.jpg
Cracked valve cover yes?

Gonna run the breather test next but I gotta get a hold of some properly sized vacuum caps...

Come to think of it, it's right beneath the oil fill cap. It could be from spillage...
 
Last edited:
30% LTFT?!

Well, crap. Went out of my way to get the vacuum caps I needed to run the test. Weather started off nice today so I figured I'd get it done. Figured I'd get a baseline before I put the breathers on just in case and whaddya know -- my long term fuel trims are up to +29% (no check engine light!). I'm still on the Lund tune. The car actually seemed like it was driving better but I did notice my gas mileage going down significantly. So I pulled the codes, and there was only one that said misfire recorded in first 1k cycles. Not good. I think STFT were also high... (+15% range if I remember right)

So I put the breathers on and let her idle. LTFT fell to +16% (STFT +0%). Higher than I had previously but half of what I had recorded minutes ago. Could it still be the valve cover? Or is my engine on it's last legs?

For now, I put the stock tune back on. I'm gonna idle it and see if it goes back to +29% or thereabouts. Either way, I'll put the breathers on and see what happens. If the same thing happens, I'll plan on getting the GT500 valve cover ASAP unless one of you guys tells me that this is the engine...
 
Last edited:
Stock tune loaded, letting LTFT relearn, it's currently at +14٪. Close enough to normal... maybe the Lund tune didn't play well with whatever issue I have going on?

Gonna drive it a bit and see what happens. Then I'll put the breathers back on and see what that does...

EDIT: Update, I think the crazy trims were caused by a loose AN fitting on my catch cans. Probably gonna re-load the Lund tune. Breathers did nothing -- trims didn't change at all. Pretty sure this is a cylinder head issue. Slight tick is more constant and audible now. Felt all around the cylinder head and feel a pulsing around cyl 1.

Gonna keep driving it and see what happens. Looks like I either need to A. Hope it's just the rockers and replace them. B. Rebuild cylinder head and hope short block is OK. C. New long block. I know somewhere I can get a NOS Boss long block. Probably been sitting a long time. It'd sell fairly cheap but not sure if it's worth the risk...
 
Last edited:
I think it's the end of the road for my bug hunting for the time being at least. The only other stuff I can think of would be cylinder head things like rocker arms but I have none of the usual noise associated with that so I think I'm just gonna leave it be and do the best I can with what I have. Lately I've been focusing on minor maintenance items. Installed a new trunk weatherseal. This surprisingly eliminated some of the clunkiness I was hearing from the rear. I didn't realize how smooshy my old one had become. I also found a loose screw inside the passenger door that was rattling around, and was able to re-adjust the rubber boot on my MGW shifter that had shifted around allowing transmission noise into the cabin. It helped -- but my gears are still loud. Also found and installed a pristine set of Boss 302 side pipes. My old ones are up for sale in the classifieds. They work fine, I just jumped at the opportunity to get a perfect set. I also re-examined my body harness. It's been on my list of things to do for a while. My mechanic re-pinned it when we did the swap and I never had a chance to see the result so it's always been in my mind as a possible cause of some of my issues. But I pulled that apart last weekend and it turns out my mechanic did a great job on it. And luckily I didn't break anything putting it back together.

Now I'm thinking about next steps. There probably isn't a lot more I can or will do, but maybe I can make a couple more tweaks...

I'll do the engine one day. Just not today.

Side note: AI is a lot less useful than I was giving it credit for. The more things I've ruled out on this car the more crazy it's ideas have become. I'm gonna stop using it as my sounding board... lately it's just been sending me down a bunch of rabbit holes.
 
Side note: AI is a lot less useful than I was giving it credit for. The more things I've ruled out on this car the more crazy it's ideas have become. I'm gonna stop using it as my sounding board... lately it's just been sending me down a bunch of rabbit holes.
I've gotten some flat out wrong information a few imes while using AI to assist with my build. That being said, it's been very helpful at times too, especially when trying to stumble around in FORscan.
 
I've gotten some flat out wrong information a few imes while using AI to assist with my build. That being said, it's been very helpful at times too, especially when trying to stumble around in FORscan.
Absolutely! I'm a history nerd and I watched a history guy that does his own research do a Youtube vid about how info can be manipulated t create "facts". I'll never trust AI for anything
 
A few years ago, a coworker got a call from someone asking why a document had been removed from our website. ChatGPT had given the person an answer that included a quotation and link to this doc as a reference. After doing some research, we determined the document never existed. ChatGPT needed some backup for an argument it was making and hallucinated the whole thing - quotation and link.

The thing to remember about most if not all AI is that it is probabilistic instead of deterministic. And it only knows about what it was trained on.
 
Top