1984 GN MAF search

Hot Air Beast

Hot Air Lover
Mar 10, 2007
250
8
18
73
Carleton Place, Ontario, Canada
Hello all hot air lovers. My '84 is currently in a Garage in South West Florida. I had a complete engine rebuild in Canada and drove south. The car performed great for 1300 miles. The it started to buck slightly, which smoothed out once I lightly touched the brake pedal; making me think of the TCC lock up solenoid. The problem got progressively worse - need to feather the gas on start up, chugging when trying to get up to speed, hard to rev up etc.

The owner of the shop owns two '87 GNs so he knows the cars.

He believes I need a MAF sensor as well as the lock-up solenoid. OK - here's the question. He tells me that the MAF sensor for the 84 is tough to find. Apparently tons were made but they don't differentiate between the turbo sfi version and the normally aspirated cars. I checked Rock Auto and they show the MAF as good for all, which seems odd to me. I see both 25007653 and 25007866 as part numbers.

Can you offer me any advice? Either pm me or send to phil@zynetonline.com
 

true85HA

Member
Oct 1, 2015
57
5
8
35
Hello all hot air lovers. My '84 is currently in a Garage in South West Florida. I had a complete engine rebuild in Canada and drove south. The car performed great for 1300 miles. The it started to buck slightly, which smoothed out once I lightly touched the brake pedal; making me think of the TCC lock up solenoid. The problem got progressively worse - need to feather the gas on start up, chugging when trying to get up to speed, hard to rev up etc.

The owner of the shop owns two '87 GNs so he knows the cars.

He believes I need a MAF sensor as well as the lock-up solenoid. OK - here's the question. He tells me that the MAF sensor for the 84 is tough to find. Apparently tons were made but they don't differentiate between the turbo sfi version and the normally aspirated cars. I checked Rock Auto and they show the MAF as good for all, which seems odd to me. I see both 25007653 and 25007866 as part numbers.

Can you offer me any advice? Either pm me or send to phil@zynetonline.com
I have a brand new MAF sensor from my 85 I pulled off im willing to seel you Phil
 

blacknight80

Member
Dec 26, 2013
534
23
18
Olds, Alberta
The new mafs also have quality issues. I've heard some work and some dont. It Seems drastic bit an 87 ecm maf t and ls maf would be the best way to solve the issue.

Sent from my SM-G930W8 using Tapatalk
 

jiho2

Sporadic Poster
Apr 4, 2004
391
15
18
Redding, CA greater metro
He tells me that the MAF sensor for the 84 is tough to find. Apparently tons were made but they don't differentiate between the turbo sfi version and the normally aspirated cars. I checked Rock Auto and they show the MAF as good for all, which seems odd to me. I see both 25007653 and 25007866 as part numbers.
New ones are impossible to find, but remans (remanufactured) are not are not so tough. The correct OEM service part number is 25007653.

RockAuto shows A1 Cardone out of stock, they've gone rebuild only (send them yours and they'll rebuild it). They show others in stock though. The ACDelco is probably correct, but showing a later OEM service revision. It's probably a re-labelled Cardone that's still in stock.

Tons were not made, and they do differentiate.

The 25007866 is for the '86-'87 intercooled motor, nothing to do with '84.
 
Last edited:

jiho2

Sporadic Poster
Apr 4, 2004
391
15
18
Redding, CA greater metro
The new mafs also have quality issues. I've heard some work and some dont. It Seems drastic bit an 87 ecm maf t and ls maf would be the best way to solve the issue.
I did misspeak slightly, there were some new ones several years ago. Haven't seen them lately. As I recall they were "wasp waist" style like the later 3800, and sold for both NA and Hot Air, and lacked provisions to bolt to the bracket on the air cleaner box. The "quality" issue I recall was whether you could max out the air flow rate. But that would only be an issue for modified motors, a stock Hot Air won't get anywhere near that, having the same hp rating as the last NA 3800.
 

crashedout1

Active Member
Feb 23, 2011
438
26
28
Lake station indiana
Convert to 87 ecm and ignition and buy a Kirban m.a.f. and be done. Dont waste your money on crap from these auto parts stores its a gamble on if they are good or you can learn the hard way being cheap. These sensors on these hot airs crap out one after the other.
 

Hot Air Beast

Hot Air Lover
Mar 10, 2007
250
8
18
73
Carleton Place, Ontario, Canada
Thanks for all the replies. My MAF lasted for 33 years so I am hopeful the one I was able to source from a member in Georgia will last as well. It was working on his '85.

As always the members on this board are great.

Phil Errett (Hot Air Beast)
 
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Hot Air Beast

Hot Air Lover
Mar 10, 2007
250
8
18
73
Carleton Place, Ontario, Canada
I just received the MAF from Georgia. I notice that the housing is slightly different but is generally set up the same (no 4 screws - plastic is bonded) (plug goes in from below just like 84). Part no. on unit is 25007699; which has been identified elsewhere on the board as being the 84/85 number.

Any thoughts?
 

jiho2

Sporadic Poster
Apr 4, 2004
391
15
18
Redding, CA greater metro
25007699 is the '85 number. GM had different numbers for '84 and '85, remans also do. As far as I know, the difference is the screen. '84 has a "chicken wire" screen, '85 has a deeper "honeycomb" screen. Can you post pics?
 

Anthony P

Active Member
Jan 24, 2007
630
177
43
Phil, my catalog is showing part # 25007699 is listed as the 1985 MAF sensor. It should be the same as '84 however the bonded plastic design change should have created a new part #. so, i'm thinking the ...7699 superceeded the '84 part #.

the pdf images that GN Venom posted above for ...7651 or ...7653 - I believe that was the part # assigned to '84 models - can't confirm that #'s exact application at the moment or when the part # was superceeded. functionally they are the same, but I know you are keeping the Beast all stock. don't know who might have a good '84 MAF with the 4 Torx fasteners. At least you get use the '85 to confirm your MAF was malfunctioning. Maybe someone will chime in who has an '84 MAF for your '84.

In the morning, you could contact a local GM dealer and ask to have 25007699 looked up to confirm when that # became active and what # or #'s it superceeded.
 

blacknight80

Member
Dec 26, 2013
534
23
18
Olds, Alberta
If you are in a pinch I have a one that the screen has been removed and one with. I was having issues that I assumed were caused by the maf so I went with an 87 ecm maf t. I dont know if either work but you can have both of these if you pay shipping. I'm in Canada so shipping will probably be 25 bucks.

Sent from my SM-G930W8 using Tapatalk
 

Anthony P

Active Member
Jan 24, 2007
630
177
43
the link i was trying to find last night regarding superseded part #'s is this. already set to 25007653. http://oemcats.com/oem-parts/25007653.html

it's not perfect....does not show that 7653 was superseded by 25007699, but I find it helpful. go to the homepage to search 25007699 and it lists a bunch of old links to dealers, etc who once had the part for sale. most of these links don't work anymore, but the site is good for part # research when trying to converse with you local GM parts counter guy.
 

Hot Air Beast

Hot Air Lover
Mar 10, 2007
250
8
18
73
Carleton Place, Ontario, Canada
Yes, the problem in Feb/March 2018 was the MAF. In fact the firm that rebuilt the engine must have used power tools to reattach the MAF as they broke the housing and more air was getting in thhan the MAF was showing. Consequently the engine was running very lean. Installed the new MAF and everything was fine until the trip down this year (November 2018). Got stuck in a backup on I 75 in Florida and backfired upon trying to exit fast. Been working on the problem ever since then. Backfire actually blew off the pipe from the MAF to the throttle body. I have swapped MAFs that I have and changed the O2 sensor. also ran a smoke test and found a vacuum leak (resolved). Engine again suns fine as long as i do not go WOT. I can ease up to 80-85 mph but if I try WOT the engine bogs and actually seems to slow down. Still trying to resolve this.
 

HotAirWH1

Member
Apr 26, 2018
84
18
8
FLINT MI
Thanks for the update. Hope you get it worked out. Trying to find a correct MAF for these Hot Air"s (84-85) is challenging. I just found a re-manufactured MAF from Duralast (part # 74-7699). Hope it's not junk.
 
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