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Discussion Starter #1 (Edited)
I searched high and low for this information and didn't find a whole lot, so I decided for a change I'd actually document one of my projects and write it up. I could tell my throttle was a little loose and sloppy, most likely due to age and the cables having stretched some, and the FSM was a little vague on how to do it. There was a write up that someone did over on the Cadillac Forum but all the pictures from it seem to be gone. And I like being able to see what I'm supposed to do before attempting, so here goes.

Also, I came up with a decent repair for the cable that connects directly to the accelerator pedal (that doesn't involve zip tying it) if it's stretched and your pedal has some slop that the adjustment procedure won't take out. This should apply to all the B-bodies as well, so if someone requests it, I'll be happy to take that portion and write it up under the engine maintenance section as well.

Alright, as I mentioned I had noticed that my accelerator pedal was a little sloppy which I confirmed with a scan tool. The reading I got was 87% angle with my foot down and about 3.9v from the TPS. I pulled the elbow off the throttle body and visual inspection showed that at WOT the blades were definitely not opened all the way. So, let's fix this thing.



Pop off the cover that says "ASR", held on by 3 tabs around it.



Next you'll see a chunk of foam and another cover. Pull out the foam and pop off the second cover, held on by two tabs on the sides.



You should now have these 3 things sitting aside. (No screwdriver needed, that was just holding down the page in the breeze.)



Next, the big plastic things on the cables are what we'll be messing with. According to the FSM, you must do the accelerator cable first, followed by the cruise control cable.



The FSM said to press and hold the adjuster button, which was where I was a lost initially. I kept looking around going, "what button?, where?" I finally found it underneath the first cable that gets adjusted, the one nearest the brake fluid reservoir. It's the square thing with the arrows on it.



I found the button to be rather stiff and difficult to hold in with one hand while trying to slide the adjuster back with the other. The easiest solution for me was to grab an old leather glove, bunch one finger under the button and carefully depress it with a medium vise grips. Do whatever works for you. Be careful not to use to much force here though, since it's all plastic and easy to break. Once the button is pressed in, it should slide back and forth easily. Slide it all the way back (away from the ASR), and release the button, locking it in the non-adjusted position.



Now slip the back end of an 1/8" drill bit down through the holes of all 3 cams. It's a snug fit so it shouldn't fall through. Don't go any lower than I did here, if you do it's possible to get the drill bit down into the gear and damage stuff when making the adjustment. Then stick a 1/4" tool (either a driver or a ratchet with a short extension) into the drive hole and rotate the entire assembly clockwise (like you were tightening it). It'll turn less than a full revolution before hitting the stops, now you have to use a little force and turn it some more. Be very careful and don't get too carried away. It will take a fair amount of force, but I'm fairly certain you could damage something if you really push on it. You'll hear what the FSM describes as a few clicks (I usually heard two in quick succession when I did it) but it sounds more like plastic stuff being destroyed. Scared me a bit the first time I did it. At that point you're done with that cable. The FSM says to check the TPS voltage now with a scan tool, and mine did improve, to 4.44v, but still only 93% on the angle, (I suspect my TPS is worn out, but I believe there's a way to adjust it by simply slotting the holes a little bit and rotating it until the reading is correct, or at least close enough). Also it states that when you depress the throttle to the floor, you may hear additional clicks from the adjuster. Mine never did, even after correcting the stretched out throttle cable.



At this point you can adjust the cruise control cable. Even if it wasn't a problem, I'd recommend it since adjusting the first cable will throw the other a little out of whack. It's also the easiest to adjust. On this one you'll see a little lever that you have to flip, that unlocks it.



This is the lever unlocked. Now you hold the throttle body itself closed, and push the adjuster back until a little resistance is felt, and re-lock it. I'd suggest moving it back a forth a few times and just watch the throttle body linkage function so you have an idea where you'll need to adjust it and how much pressure is too much (ie - enough to start opening the throttle body). Then go ahead with the adjustment.



With one hand, hold the throttle body linkage closed.



And while holding that closed, use your other hand to push the adjuster back until a little resistance is felt, and then flip the tab back into the locked position with a finger. And that's it, the adjustments should all be complete. Remove the drill bit from the ASR if you haven't already (the FSM never actually indicated at what point to remove it, or if it did I missed it, but I tried the cruise control cable adjustment with it in and out and found no difference), and put the covers and foam piece back on.



If you did it correctly, you should now have 4.5v from the TPS (I've heard up to 4.8v is still ok, but higher than that and the PCM will get mad and go into limp mode) and somewhere close to 100% angle. As I said I still didn't get that, but I still have the pedal to deal with, and possibly the TPS itself. If you don't have anything else to fix, now's the time for a test drive. If it was far enough out of adjustment, you may notice a small improvement in throttle response. If it was far enough that the PCM was never achieving WOT and going into PE mode, you may also experience a slight performance increase. And now on to the accelerator pedal cable fix.
 

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Discussion Starter #2 (Edited)


First things first, take off the sound insulator. Just two screws at the front edge, mine were both 7mm.



And there's one wing nut at the back, right above the accelerator pedal assembly. Also note, that this wing nut screws off, but to reinstall just put it in place and push it straight on, it's thin enough that it's meant to do that. Makes putting it back on much easier. I also recommend putting the front screws back in first when reinstalling, otherwise the whole stupid thing will want to lay on your head.



Now you should be able to see that when I lift up on my gas pedal, a roughly 1/4" gap shows up between the cable and whatever that spring thingy is. The best repair I've found so far, since this cable doesn't seem to be adjustable, is to just put a zip around the cable in that gap. I wasn't crazy about that idea and I doubt it would last very long, especially if you're aggressive with the go fast pedal.



I popped into one of my local hardware stores, poked around in the various drawers of things in the nuts and bolts aisle, and eventually came across this. It's an aluminum cable stop. They come in different sizes, and I forgot to write down which it was, but the smallest one in the box was labeled 1/16", and this was the next size up. It's roughly 1/4" long as well as diameter.



Now to get it onto the cable, it needs a slot. A bench vise would work much better, but I don't have one so I stuck it in my small needle nose vise grips.



And then cut a slot with a hack saw with a thin blade. I wasn't too sure how big I was going to need the slot, so I used the thinnest blade I had on hand. Starting the cut was a pain in the tuckus, and having it in a bench vise would help dramatically. Even so, once I finally got the slot started, I was able to cut it in just a minute or so and without removing any of my fingers.



To deburr the inner hole, just stick a 7/64" drill bit in from either end, twirl it around and then repeat from the other end. This would also be another way to check for the correct size of one of these things, a 7/64" drill bit should just fit through the hole. I also found that my slot wasn't quite big enough to fit it over the cable, so holding it with the vise grips again I stuck a small flat blade screwdriver into the gap and carefully spread it out until it would go on easily. Don't worry if you mark up the slot, it won't matter in the least.



This part will probably suck the most, actually getting it on there. It should just slip on, but you'll almost certainly need both hands up in there so there's going to be cursing and the possibility of getting stuck in an uncomfortable position, especially if you've got a little too much padding around the mid-section.



Now the final step is to close it up so it can't come off. I used my largest vise grips for that, and be careful not to crush anything else, but it should squeeze together relatively easily. The bigger the tool here, the easier it'll be. I have one friend who's a total bear, he could probably crush it with a tweezers, but until I tried my largest vise grips, I wasn't even budging it. I got it nearly closed all the way, which it plenty. Even though it can still spin around on the cable, the slot is way too tight now for the cable to ever pop out of it.

At this point, put the insulator back on and go for a drive. I attempted another go at adjusting the other cables, but after doing so I still got the exact same readings from the scan tool. BTW, a scan tool isn't necessary, any method of getting into the PCM is fine. If you have an adapter and TunerPro or Datamaster or whatever, those will also show the TPS voltage for sure, and maybe also the angle. Possibly you may be able to back probe the harness with a multimeter to see what the voltage reading is, but I don't know for sure since I had no reason to try.

And while mine still doesn't indicate that it opens all the way, visual inspection of the throttle body revealed that my blades now open all the way. I also noticed that before I put the covers back on the ASR, all the cables have a nice solid feel, only a slight give before things started moving, whereas before they were all fairly loose and sloppy feeling.

If you would encounter any driveability issues, you may have adjusted something too far, just redo it and don't get as crazy with it. Mine seems fine so far, but I forgot to test my cruise control. Also my pedal feels much better, especially at very slight throttle. I also have a slightly finer degree of control at take off and the car is a little quicker to respond from a stop. My idle seems just fine, when I pulled up the RPM display on the HVAC (I'd already put away my scan tool) I was idling between 600-700 RPMs.

The only other thing I can think of would be on the pedal fix. Since not every cable will have worn the same, you may have more or less stretching than mine did, so you'll have to find a way of dealing with it. If it's less, the cable stop I used would be fine, it would just need to be ground down a little until it takes up the slack without actually pulling back on the cable. If you have more stretch, you'll have to find something else, or try shimming it out with washers (do the same thing, cut a slot in them, and once installed squeeze them shut with a vise grips).

And finally, I still need to deal with the TPS. I believe someone has a write-up on that somewhere, but if not I'll see if I can figure it out and add some more pics of that repair.
 

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Discussion Starter #3 (Edited)


I realized that I never checked the TPS while the engine was actually running, so I plugged the scan tool back in and gave it the beans. Turns out I still get the exact same 4.44v, but now it shows the angle at 100%. And the reason for that is... I have no idea. My best guess would maybe be the brand new garbage battery from Walmart, (I didn't put it in there, the guy I bought the car from did and it was already shot when I got it, but it was still under warranty so they put another new one in for free) which no matter what I do to it, will only ever read 12.0-12.1v with the engine off during nice warm weather. I plan to ditch that for something better soon-ish.

So since there's literally a 2v or more difference between engine off and engine running maybe it's causing the TPS to give different readings (even though both were at the same 4.44v?). Or maybe the PCM just acts differently when it's running, or that voltage difference is affecting the PCM, who knows. At least I won't have to fiddle with the TPS. And on the test drive my butt dyno definitely noticed that it seems to have a little more punch once it winds up, I would assume because now the PCM is actually detecting a WOT condition and entering PE mode.

But whatever, it's fixed and I'm happy. Time for whiskey. >:)
 

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TPS auto zeroing

My 94 Caprice manual states there is a TPS auto zeroing function. It re calibrates the TPS when the car is idling.

This may be why you had a different WOT before you started the engine.
 

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Discussion Starter #5
My 94 Caprice manual states there is a TPS auto zeroing function. It re calibrates the TPS when the car is idling.

This may be why you had a different WOT before you started the engine.
I haven't been able to confirm if that's the case or not. I spent about 15 minutes chasing references to the TPS throughout the FSM and finally found mention of the auto calibration, and in mine it says it re-zeros it. I'm not sure what exact conditions must be met, but as long as the car is at idle and the TPS is giving out anything from 0.3-0.9v, the PCM will set that voltage as the new 0%.

It doesn't say and I have no idea if that would have any affect on the WOT %. I'd have to recheck with the car off and running to see if I still see different values or not. One thing I didn't care for was if I ever replace the TPS, it says you have to initiate a relearn procedure with a Tech 1. I was under the impression that the OTC/Matco/etc 4000Es were the same as a Tech 1, but I haven't found yet where to initiate that sort of stuff from it. I also could just be misinformed on the capabilities of these units.

I'd also be willing to bet there's another way to initiate the learn procedure, since there always was if a Tech 1 wasn't available and my older FSMs always detailed alternate methods for everything, but this manual only ever says to use a Tech 1 and almost completely omits any other methods of accessing or doing anything with the electronic systems.

So for now, at least according to the FSM for my car, everything related to the throttle cables and sensor are within spec and the car drives fine (I also tested my cruise control this morning and it works perfectly). I'm considering it fixed and unless something else crops up I don't plan to mess with any of it again.
 

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Well done writeup. And the pics go a long way to keep head-scratching to a minimum. Armed with this info I'll get out there and see what problems I can fix. Or create. cwm4
I'm sure it'll be clear when tearing into it, but I'll be interested in seeing exactly what is it about the first accel cable adjustment that still leaves remaining slack that necessitates the second adjustment at the pedal involving the aluminum cable stop.
 

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Discussion Starter #7
Well done writeup. And the pics go a long way to keep head-scratching to a minimum. Armed with this info I'll get out there and see what problems I can fix. Or create. cwm4
I'm sure it'll be clear when tearing into it, but I'll be interested in seeing exactly what is it about the first accel cable adjustment that still leaves remaining slack that necessitates the second adjustment at the pedal involving the aluminum cable stop.
I'm glad that it'll help someone, and if there's one thing I love, it's plenty of pictures. Once I figured out how to correctly operate the adjusters it was super easy to do it. And after all my messing around with it, I was able to do the entire adjustment procedure in under a minute.

I did finally figure out what the spring thingy is on the cable above the pedal, according to the FSM it's a spring loaded automatic adjuster whose function is to prevent stretching of the cable. Basically if the cable is too tight and when you put the pedal down rather than stretching the cable the spring compresses to give a little more travel. And I did notice that if I mashed the throttle all the way to the floor and then dig into the carpet I could just feel a little bit of resistance from that spring compressing, so I feel like I have mine perfect.

I could not however find anything about manually adjusting that adjuster in the FSM, so I don't know if it can be or not. I did poke at it a little, but wasn't able to move it since no matter which way I twisted around (and I had the bruises on my side from the door sill the next day to prove it) there just wasn't an easy way to get both hands far enough up there to grab onto both the cable and the adjuster to try and move it.

If you do figure anything out with it, I'd be very interested. And as much as my pedal feel has improved, I have discovered one complaint, because the accelerator is raised up now, I occasionally catch the side of my foot on it when I move it from the brake pedal to the accelerator. It's a minor thing, but it's a little annoying since I'm not used to the new position yet. I'm sure I'll adjust after awhile though.
 

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Discussion Starter #8
Two quick things: first if it would be helpful to see larger versions of any of the pictures, I created an album where I hosted them. The password is "Fleetwood". (I didn't really want the album to be completely public.) Second, when I just went in to creat the album, I noticed that apparently the free account is actually only a 1 month trial, (I need to confirm that yet, but it appears to be the case). So the pictures could end up going away. Anyone know of a better site to host the pictures? I can redo the links once I upload them somewhere else. This was the first time I tried using pictures and discovered that I couldn't upload pictures directly, only external links to pictures.

https://imageshack.com/a/XMZM/1
 

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Check out Photobucket. Big res, security/access selections, seeming noninvasive hosting.
 

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Discussion Starter #10 (Edited)
Check out Photobucket. Big res, security/access selections, seeming noninvasive hosting.
Resolution actually wasn't the issue, I was just unfamiliar with how to handle pictures when posting a thread on this forum. I first tried the original size which looked ridiculously huge, so I played around with linking to different sizes until they were roughly the same size as the block of text, but the box you write in and the box the threads are displayed in are different, and I don't know what would happen if I had just used the huge versions. Basically I'm just unfamiliar with posting to this forum and forums in general since I've never really been into that. I'll figure it out though.

I had also considered photobucket, but I have issues with their webpage (technical, not personal). I run a highly customized and tweaked ad blocker on my browser, and at this point I couldn't tell you the last time I saw an online ad. I don't see commercials on youtube, I don't get ads on pandora, nothing, anywhere, ever. However some sites are starting to get wise to that and if they detect ad blocking, they in turn block access to their content. Photobucket is one of those and unless I turn my ad blocker off, I never see any content hosted by them. So my choice to try imageshack over them was a decision based purely on convenience for me. But if the imageshack thing turns out not to be truly free hosting, I'll probably switch the images over to photobucket and just deal with it.
 

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Discussion Starter #11
It's been a month since I did this and thought I'd give an update, so far it all still works perfectly. I have absolutely no slop in the pedal itself or in the cable at the throttle body. I still need to upload the pictures to a different website and update the original post, so the pictures might disappear in a couple days, but I'll fix it.
 

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Discussion Starter #12
Interesting, the pictures appear to all still be here, at least when I view the page. I thought they'd disappear at some point due to the site I used to upload them. If everyone else can see them fine, I'll leave it alone. If for some reason they aren't showing up, I already have them re-uploaded to a different site (photobucket) and can swap out the links at any time. Actually that's what I came on here to finally do, but since it appears I don't need to I'll wait and see if anyone is unable to view them.
 
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