Iron Duke / Early air cleaner Questions! (Page 1/2)
82-T/A [At Work] JUL 11, 08:49 AM
Hey guys, couple of questions about the original 84-86 air cleaner assembly for my daughter's 1985 Fiero 2m4 SE w/ 2.5 Iron Duke and 5-Speed, hope you can help:

- Thermostatic Valve: Ok, my daughter and I keep doing this. We're usually really good about taking pictures of things and how they are oriented, but this time we forgot to take a picture of when she removed the thermostatic valve (so we could repaint the air cleaner). Would someone mind taking a picture so that we can see what direction it goes in? As well, would someone mind terribly taking a picture of the underside so we can see which side (also) had the vacuum line going to the THERMAC? Also, anyone know if they sell new thermostatic valves? We cleaned this one with brake parts cleaner, and it looks pretty solid... but just looking for options to make it "like new."

- Thermac: We found an original OEM replacement for the THERMAC (super rare I guess) and are installing it. Question I have is... is there any kind of lubricant that you guys use to make sure the thermac door opens and closes freely? It feels like it's catching on one side of the air cleaner. I sprayed some WD-40, but I don't think that'll last too long, and the last thing I want is for it to get stuck open.

- Stickers: Our air cleaner showed evidence that there was a sticker attached to the side of the air cleaner assembly... it was mostly faded, but looked like it said GM. Anyone know what would have been on the side? (it was 1" by 1"). I went looking at Rodney's stickers that he sells, and didn't see anything. Finally, is the "Tech-4" only from 1987+, or would the 85 or 86 also have had the "Tech-4" sticker on the air cleaner neck? I've seen so many of these cars in the junkyard over the years that I can't even remember what's what now... and now that I'm finally going back to junkyards, there's not a one in the yard that I see.

- MAP Sensor: Bonus question, I assume the green (plug insert) MAP sensor is the correct one to use, correct? I have several from various pick-n-pulls over the years, all GM. Is there any benefit to going to a better / higher MAP sensor like on the V6 Fiero?
Thank you!
82-T/A [At Work] JUL 11, 09:13 AM
Well, I kind of answered some of my own questions (sorry, haha):


- Thermostatic Valve: I found a picture of the orientation, as well, I also found a picture of which port is used for what. Still interested to know if anyone knows where I can purchase a new thermostatic valve though.

- Stickers: I found an image of an air cleaner on eBay that actually has this sticker (posting it below). Still want to know though if Tech-4 was ever used on the 85-86 air cleaner assemblies, thanks!

- MAP Sensor: Green MAP sensor is the right one, but still curious if there's a better (newer) replacement, similar to what people have done with the V6 Fiero.

- Thermostatic Valve: Anyone know what grease I should use to ensure the flap is lubricated and will open / close properly with ease?




I know it's silly, but anyone know where I can get this sticker?


Thank you!
theogre JUL 11, 11:39 AM
Tech4 logo is only 87+ dukes because uses DIS & other Factory upgrades/updates.

⚠️ Warning: THERMAC door was installed Dry, No Lube. If you "must" lube a Metal door, only get lube w/ Dry formula Graphite or Teflon. Any wet lube holds dirt & make More problems often very soon. Some vehicle has "plastic" thermac doors that may hate even those. Both are Dry but many have solvents etc that hate plastic before they dry. Even "pure" Dry Graphite powder doesn't play well w/ many plastics & soft metals.

Most Vac plumbing is on VECI label on rear deck for given setup including Thermac line because required under EPA/DOT Engine Emissions rules.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

[This message has been edited by theogre (edited 07-11-2024).]

82-T/A [At Work] JUL 11, 12:04 PM

quote
Originally posted by theogre:

Tech4 logo is only 87+ dukes because uses DIS & other Factory upgrades/updates.

⚠️ Warning: THERMAC door was installed Dry, No Lube. If you "must" lube a Metal door, only get lube w/ Dry formula Graphite or Teflon. Any wet lube holds dirt & make More problems often very soon. Some vehicle has "plastic" thermac doors that may hate even those. Both are Dry but many have solvents etc that hate plastic before they dry. Even "pure" Dry Graphite powder doesn't play well w/ many plastics & soft metals.

Most Vac plumbing is on VECI label on rear deck for given setup including Thermac line because required under EPA/DOT Engine Emissions rules.




Thanks Ogre... I have some of that dry moly lube in a green spray can that someone else recommended here (maybe Sleek Fiero). So I'll make sure I clean out the wet lube and use that spray. It just occurred to me that my daughter's Fiero is also missing the emissions sticker. I wonder if I can get new ones of that too. It looks like it had been repainted.

Maybe it's me being somewhat OCD (never officially diagnosed, haha), but I really want to figure out what that sticker is on the side of the canister. I'm guessing it has somethign to do with the "Keep your GM all GM" marketing that defines what the specific air filter is needed...


Thanks!
theogre JUL 11, 03:27 PM
Maybe was replaced or is a factory part & 2 numbers are PN
One w/ barcode likely GM number, matching 22p or not.
410-7584 seem to be ACdelco format for outside sales. Or a air filter number to go w/ this.

GM & AC changes PN all the time for various business reasons.
Only some common numbers stay closely to same w/ added letters. Just look at PF52 etc as contract makers change the filter or change the companies entirely as contracts get rebid. GM & ACdelco haven't made most parts in decades. Other things like chemicals & filters where contracts. D EX Cool.... Delco contract to Texaco to make that & way more coolant, oils, grease, etc.
82-T/A [At Work] JUL 11, 04:44 PM

quote
Originally posted by theogre:
D EX Cool.... Delco contract to Texaco to make that & way more coolant, oils, grease, etc.



Oh **** ... mind blown. I had no idea, this makes total sense to me now.

I ended up buying the above air cleaner. Among other things, it came with the proper elbow fittings for the vacuum lines, a perfect EGR plastic vacuum hose that connects directly to the THERMAC, and I'll get a closeup of that sticker... lol.

My daughter is also not happy because she screwed up the repainting of the air cleaner lid... so rather than sand it all down, we'll use that one, and hell... we have a spare that I can send to someone if someone needs one.


Thanks!
theogre JUL 12, 11:09 AM
Other "GM" products are rebranded whether or not product is change. Example: Old GM 1050011 "Windshield cleaner" was just relabeled Bonami original formula & had bonami seal covering the holes on top. Yet oddly Bon ami always say Don't use it on glass even tho labeled w/ old "never scratch" logo for decades. Likely because so many types of glass w/ some way easy to damage then others.

Can still find new sealed GM cans on Ebay from time to time...


Bon ami had 2 formulas in recent years w/ red & gold around bon ami name. was red one the original formula.
Seem they drop the "new formula" but may find it in store or on self elsewhere.
82-T/A [At Work] AUG 11, 01:21 PM
For anyone who cares, I bought that air cleaner and carefully removed the sticker that's on it. I'm obsessing on this like my daughter, and I'll probably try to reproduce it on vinyl. It goes onto the side of the air cleaner assembly.
82-T/A [At Work] AUG 11, 07:52 PM
And for anyone who's as anal as I am...





And this is what it looks like printed (I ordered 50 of them because I more or less had to).





The barcode is also a different barcode "font," so that does kind of suck. But any Symbol device will be able to natively decode that barcode as the correct number above. I just couldn't find the original barcode font that GM used. I only need one, haha... so I'll keep a few of them, and then probably give the rest of them to the Fiero Store or Rodney Dickman if they want them.

[This message has been edited by 82-T/A [At Work] (edited 08-11-2024).]

armos AUG 12, 07:53 AM
V6 and 4cyl use the same MAP sensor, unless there's some modification I'm not aware of. Since both engines are NA, they have the same range of pressures to report and the same 8-bit resolution.
If you upgrade to say a 2bar MAP sensor, you'd just be losing half the resolution to support a wider pressure range that the MAP will never see.
I know you've talked about aftermarket ECMs but I don't remember if you're actually using one here. If so, then maybe there is something better that your ECM can use.

My 86 Grand Am 2.5L, and another my sister used to have both had the "Tech-4" badging on the air cleaner. My 84 Fiero did not. I've never seen the air cleaner on other years of the 4cyl Fiero, so I don't know when Fieros started to use that badge.
I've seen an ad on youtube for a 1985 S-10 with the "Tech-4" engine, so at least Chevy was throwing the name out there that early. Doesn't mean they were badging it on the air cleaner yet, though.
I can't find it on youtube anymore, I downloaded it ages ago.
I did find this video of an actual 1985 S10 2.5L - and it does not have the "Tech-4" badge.
https://www.youtube.com/watch?v=XBEZP0_erns


There's certainly a market for emissions stickers - CA requires one to pass an emissions test - so there's probably somewhere you can buy them.

If not, then maybe this image is enough to be able to make one.

<came from a late 84 with 49-state emissions>
If you do that then maybe somebody can post a picture of the 85 sticker just to make sure the details are right.