IAC/TB vaccum line cant find where it goes?

[GTU89]

1990 GTZ Quad 4 5spd.

Where does this vac line go?? Pics below of it 2nd pic is the vacum line on the "right" of it headed towards the airbox/battery. Has a screw in the end of it but obviously it is supposed to be hooked up

[GTU89]

Also my gas gauge drops to empty when warm randomly then the engine sputters/won't rev and trys to die. No CEL or codes.

[1988GTU]

I think that one goes to cruise. Other one goes to FPR. Short in the harness/sending unit for the pump. Most likely harness.

[GTU89]

I think that one goes to cruise. Other one goes to FPR. Short in the harness/sending unit for the pump. Most likely harness.

Ok thanks! That would probably be why the cruise does nothing at all.. only had the car for 3 days so I am not completely familiar with it yet.

Drop the tank for the harness?

[1988GTU]

You can pull the back seat and check there. If u really wanna avoid dropping the tank, drilling out the two rivets and pulling it thru to disconnect is an option for isolating a possible issue.

[GTU89]

You can pull the back seat and check there. If u really wanna avoid dropping the tank, drilling out the two rivets and pulling it thru to disconnect is an option for isolating a possible issue.

Would that present the issue when warm only though? Wouldn't it do it when cold/coolish too? Runs completely perfect until its warmed all the way up.

Has a new O2 sensor but now its throwing code 13 (O2 sensor circut open or unresponsive)

EDIT: as of now it wont even crank or anything

[1988GTU]

No power? Check the battery cables and check them to the starter. Also check the starter/

[GTU89]

Turns out the starter wire is corroded to hell.
Any tips on the fuel pump wiring? Any common areas/connections?

[1988GTU]

The pump usually just shorts out internally. I have had one GM plug connector have a pin corrode pretty bad, but that was for a mid 90's CK truck.

[GTU89]

Okay well a little update. O2 sensor is sorted out and IAC is sorted out (both new).

No CEL anymore. When it's warm (and i think a bit when its "colder") it seems like it sputters/hesitates a bit and while idling it'll sputter and die about a quarter to half the time you can "save" it other time it'll just sputter and die if you try to save it while idling. Gas gauge doesn't move anymore when it sputters now and works correctly and fuel pump sounds healthy when you turn the key forward.

It seems kinda like if you hold the rpms at ~2000-2500 while in neutral its fine but once the rpms drop to idle it drops further and dies about half the time.

[1988GTU]

Does it have a hard time staring?
Check the plugs conditions?
Flooding out?

[GTU89]

Does it have a hard time staring?
Check the plugs conditions?
Flooding out?

Starts like new. Ill check the plugs and not sure definitely was rich at one point atleast the oil is extremely gassy and in need of a change.

[GTU89]

What size bolt goes over what i can best describe as the "shift arm" on the transmission? the one that has the cable that I think controls side to side motion on the shifter. The bolt fell off driving down the road and the shifter will not go side to side to go into gear.

The hesitation and bad idle disapeared oddly

[1988GTU]

The 10mm that goes on the stud? I think an alternator nut works in its place. Pic?