4cyl 84 Fiero sputters UPDATE!!!

General Fiero Maintenance including oil changes, air filters, suspension refreshes, restorations, painting, etc.

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Hollywood
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4cyl 84 Fiero sputters UPDATE!!!

Post by Hollywood »

:unknown: So i changed the starter solenoid now when the car cranks up it sputters and eventually dies... Things i have done, unhooked battery, removed vacuum lines under intake filter... Nothing else i can think of during this procedure... What could be the cause?

Update: So the oil pressure gauge(after market) is sitting at 0 psi. Whats up with that? What could be the issue there?
Last edited by Hollywood on Mon May 18, 2009 1:16 pm, edited 1 time in total.
p8ntman442
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Re: 4cyl 84 Fiero sputters

Post by p8ntman442 »

is your map connected back up to the vac source?
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Hollywood
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Re: 4cyl 84 Fiero sputters

Post by Hollywood »

p8ntman442 wrote:is your map connected back up to the vac source?
Not completely sure what that is but i checked all vacuum lines and did not see anything unplugged. Is that one in plain site. I don't recall unplugging anything more than what i plugged back in... I do see some loose connectors that i am taking pics of now. But these look like the work of the previous owner. Meaning they never were plugged in and the car did not sputter. I did not get this sputter until i just changed this solenoid... So what else could it be besides vacuum? Could it be the tps? and here are the jerryrigged loose connectors.
http://i668.photobucket.com/albums/vv43 ... G00175.jpg
http://i668.photobucket.com/albums/vv43 ... G00174.jpg
http://i668.photobucket.com/albums/vv43 ... G00176.jpg
Not the best pics but they look to be coming out by the distributor...
Hollywood
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by Hollywood »

Also there was a loud noise coming from the front of the car top right corner of the radiator sounded like... And i didn't see the fan kick on.
CincinnatiFiero
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by CincinnatiFiero »

The MAP is the manifold air pressure sensor, also heard it called manifold absolute pressure sensor. On the 84 tech4 it clips into the side of the air cleaner. If you can't find it, I have an unmolested all stock 1984 with 10k miles I can take reference pictures of tomorrow if you need some.

Image

The fiero fuel pump will not kick on without oil pressure. The oil pressure switch has to see oil to send power to the relay, then to the pump. But you said it is is starting, maybe the switch is iffy? You could try to hotwire the pump somehow to bypass the oil sender.
Hollywood
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by Hollywood »

That sounds great but i don't have a clue how to rig it to bypass the oil sender...
CincinnatiFiero
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by CincinnatiFiero »

Behind the C500 block you'll find the two connectors for the fuel pump. 1 is power one is ground one is the gauge. Ground the black one. Give 12v to one of the others if the fuel pump whirrs, you were right. I can look at my 84 sending unit tomorrow night, it is too dark right now. Do it with a friend. Have him start the car while you work the fuel pump. Have him put his ear on the center console too to see if he can hear the pump working. If it keeps running hot wired you know you've got a wiring issue, relay issue, sensor issue, something. If it still dies, its something else.

This is presuming you think it is a fueling issue, it could be a load of other things.
p8ntman442
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by p8ntman442 »

Cinci, is the 84 different than the rest?

On most, the FP relay and the OP sender are parallel paths to provide juice to the FP. Your saying they are in series, which I believe is NOT the case.
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CincinnatiFiero
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Re: 4cyl 84 Fiero sputters UPDATE!!!

Post by CincinnatiFiero »

Sorry I worded it poorly. No the relay and oil pressure switch are the same as the other years to my knowledge.

The 84 fuel pump sender is different and it uses two connectors to plug into the harness, the later cars use one 3 pin connector. The 84 C500 is also in a different spot, but I think you already know this.
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