Whats a Piston

OK so I got my 86 GXL running tonight, but found a saw blade zip tied to hold the AIR FLOW METER open a little bit. When I removed this bit of jankity redneck fix, I found the car wouldn't start. So, do I put the saw blade back? Or is there a better way to resolve my problem?

These are the engine related mods... (Bought it like this)
1986 GXL
Header
3 inch exhaust
Cone air filter, sort of SRI style.

<a href="http://s687.photobucket.com/albums/vv238/andylenehan/Mobile%20Uploads/?action=view&current=1229091909a.jpg" target="_blank"><img src="http://i687.photobucket.com/albums/vv238/andylenehan/Mobile%20Uploads/1229091909a.jpg" border="0" alt="Photobucket"></a>

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Omixeo

iTrader: (1)

Get an AFM that's not broken?

Battle Cat

iTrader: (78)

yupp. get a new AFM

Whats a Piston

Well is it a sure thing that it's broken? is there a good way to test it? I have a digital multimeter and access to almost any tool I need. I just don't know the range of resistance that is normal from the AFM...

Nick_d_TII

iTrader: (6)

http://www.teamfc3s.org/main/factory...ual/1986_1988/

Test. If Not within Spec. Replace with one that is.

Good Luck!

rotarygod

iTrader: (1)

I suspect that they had taken the afm apart and messed with the spring tension. That would alter the amount of fuel that gets sent in per amount of flapper movement. If they have to hold the door open slightly it's because there is clearly not a correct a/f ratio. There is no way to tell where the spring should be set once moved so the only fix is to replace it.

RotorBalls

iTrader: (1)

haha gotta love ghetto riggin

HAILERS

Could be several things like mentioned above.

Let it be known that the fuel pump only runs on a series four IF: 1. THE KEY IS held TO start...............2. The engine actually starts up and then the fuel pump switch internal to the AFM MAKES.

I'd suggest the previous owners have mucked around and now, when the key is HELD to START, that signal is not going to the circuit opening relay which in turn means the fuel pump aint a running when you try to START the engine.

I'd suggest the muckers MIGHT have gone to the afm and stuck the blade in there so the fuel pump switch internal to the afm MAKES so the pump will run when the key is put to START or frankly anytime the key is put to ON or bettter if what I suspect is true.

If you remove the black plastic cover off the afm and look, You should be readily see this set of contacts MAKE when the vane is slightly moved aft. It should not MAKE if the engine is at rest and the vane is let go of.

The remark above in another post is probably right......get another non messed with afm. NO WAY to get it back to stock if they did not mark the original position (almost a true statement).

Normal series four work as follows......key is put to START........the signal for START goes to the starter solenoid and also branches off to the circuit opening relay to run the pump and also branches off to pin 3B on the ECU to let the ECU know that the car is being started so it will use a internal FUEL START MAP for fuel delivery during STARTING (in lieu of the afm for fuel til 500 rpm is reached).

Series four fuel pumps on the original factory config did not let the pump run unless the key is put to START or the engine actually ran and pulled the vane of the AFM aft approx 1/8 inch or so.

There, I've said the same thing three different ways at least.

If memory serves.........that swith is adjustable. Can't believe they stuck a blade in there to keep it open. Dumb and ignorant thing to do.

KompressorLOgic

iTrader: (6)

lol wow that is crazy never seen someone do that before.

Omixeo

iTrader: (1)

Hailers is brilliant.

LargeOrangeFont

iTrader: (7)

Not to Hijack, but I just tested my AFM, per the testing outlined in the FSM and everything is fine except for the Intake Air Temp sensor. I get no reading at all when performing that test. My AFM looks to be completely factory sealed and not tampered with.

This test was related to my problem in the thread started here.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s4-na-goes-lean-steady-state-cruise-878705/

rotary#10

iTrader: (38)

lol i put a plastic stick in the afm in my s5 to hold it open to make the car run. LOL its a bad AFM for sure.

Whats a Piston

I tested the AFM and its good. I noticed a bunch of **** on the exhaust side of the engine has been ripped off. Like two rotating things on the either side of a big hole thats been covered by a home made plate.

The car has a hard time starting (20 degrees out F) but once it gets going it seems to run strong, but have a hard time idling, then when its hot it wont start at all. I will snap a pic of my this jankity patch job, and maybe one of you can help me figure out what to do.

A big thanks to Nick D for the test procedure! And everyone else contributing.

HAILERS

If you got no reading at all, then pull the black plastic cover off and see if the two connectors in my attached jpg are attached or not. They are the ones I put a red X on. You can follow the black wires and they go directly to the temp sensor.

Even if the circuit is open, the ECU defaults to a given temperature of ???? I forget right now the temp.

Just in case: The afm might very well read the readings given in the FSM but be shot to hell if someone went in there and loosened the spring tension or tightened the spring tension. The readings would still be to the FSM. Not the way to prove or disprove is the afm has been tampered with. Just two teeth of more tension or two teeth of less tension will make the engine run quite a bit differently than Norm.

Whats a Piston

Ugh. so theres no way to know if my afm is good? cuz i only paid $300 for the car, and i don't wanna buy another AFM if it can be avoided. The problem seems to be related to engine temperature. My friend said his jetta suffered a similar problem when its engine temp sensor failed. ALSO my temp gauge in the cluster doesn't read anything. Any ideas?

PnoyRx7

iTrader: (3)

you paid 300 bucks for it , and its a rx7 , you would be very lucky not to fix anything and should go buy some lotto tickets . i paid 1000 for mine minor problems here and there , just spend the money and fix it properly .

Whats a Piston

Im not trying to cheap out. I just don't want to buy a $300 part if it's not bad. I'm being told I can't tell if it is working correctly... Anyways don't think it's the AFM.

Does anyone have any ideas related to it's problems with hot starting? If i don't find some answers I'm parting it out.

NoPistons!

iTrader: (3)

Build a carb manifold.

Problem solved.

No leaky fuel injectors to replace/rebuild, no pd to replace, less wires, tune with a screwdriver.......

That's just an opinion. Dont take it to heart. I'm sure someone will though.

killalot13601

iTrader: (5)

$300 dollar part? I am selling one for $40 shipped. Out of a running car.

nycgps

iTrader: (4)

I paid 1K for mine and I spent 3 K+ on it already just to make it "safe enough to drive around"

you paid 300 and expect it to run correctly?

HAILERS

The FSM gives basic *ringouts* of the wiring and values for those ringouts. It does not confirm if someone messed with the spring tension of the AFM which changes the performance of the afm.

Engine temp for the ECU is thru the water thermosensor on the back of the water pump housing. Two pin/two wire outfit that interfaces with the ECU pin 2I (memory). This input has a LOT to do with engine performance although if the wiring is broken b/t the sender and ECU the ECU defaults to a fully hot engine. Something like 176* F.

The water temp gauge gets it's input from the sender next to the oil pressure sender on the left rear side of the engine. A one wire outfit yellow/red in color if memory serves (might be yellow/white, see FSM wiring diagrams). This gauge and sender has zip to do with engine performance.

Looking at the black plastic cover over the afm internals tells a lot. If it does not appear to be monkeyd with, then the afm might not have been fooled with. The original RTV holding the cover in was a somewhat clear to slightly yellow color and not smeared around the cover. One messed with might have black or red RTV and the apperance might be.....sloppy.

rotary_bünta

iTrader: (3)

wow thats some ghetto *** riggin.

AGreen

iTrader: (11)

pffthhhhh!!! HAHAHA!!

Look man, the afm is bad. If the car won't start without **** stuck in the AFM, then it has to be bad. Post a wanted ad for one, I'm sure someone will get you one on the cheap. You can also connect a jumper in the yellow connector behind the airbox. That will turn on the fuel pump with the key on. That way, you can determine if the afm has been tampered with. If it doesn't run with the sawblade removed, and the jumper in, then get an AFM. If it does run, then you can run like that until you figure out how you're going to pay for an AFM.

rotary#10 : I thought s5 uses a heated wire?

classicauto

iTrader: (3)

Plunger style. Same as S4, just a different method/shape/wiring. Its no heated wire MAF though.

Whats a Piston

I'm sick of comments like this. NO I DID NOT EXPECT IT TO BE PROBLEM FREE. I'm asking for help, so if you can't help shut your mouth.

I will inspect the rtv on the AFM, thanks for that thought. And thank you for the location of temp sensors, even if it doesn't fix my problems, I want a working gauge. Thank you for the new info, I'll try some things out, in the mean time if anyone has any other ideas, or wants a decent RX7 for $600, let me know.