my friend just purchased a 88 FC, im pretty sure its the 5th and 6th ports not opening, but i cant pull them out without stirpping the screws so i didnt bother trying, but i sprayed some WD40 on them and pushed them up and down with my fingers to make sure they move freely. but it still bogs down around 4000rpm's and has no upper power, what should i do to help make them work?

 

SEARCH!!! J/K... I do believe its the gounds. Someone correct me if I'm wrong.

 

Or clogged cats, or TPS problems, or fuel filter, or.......

 

i know that on the level sensor for the radiator its all jimmy rigged, instead of the sensor wire going to the sense in the radiator its just grouned into the frame. its not even connected

 

That'll just keep the buzzer from sounding, nothing to do with the hesitation.
BUT *WARNING* if someone disconnected that sensor, that means the car *could* have overheated at some point in it's life. Bad juju.

 

check the plugs!!!!!

 

i'll do a compression test on it and check the plugs out and see how that goes

 

blah blah..

kk.. so the car feels like it hits a "brick wall" at 3800 rpm? could be secondaries not coming on.. most of the time, thats been the only truth with that kind of thing. with malfunctioning ports, the car will still accelarate most ly normally, just lose 20hp. if your secondaries fail to activate, the diff is more like 80hp. you can tell the diff easily.

so if it feels like its just bogging alittle, could be clogged cats. if your 5/6ports are in question, simply unhook the little vacuum line at a T junction in front of the pass firewall, and blow into it. the ports should move with alittle pressure (3psi). if this works, then it could be cats clogged, in which case, drive the car for a bit, and see if theyre glowing..thats pretty much the only way you can check w/o removing them.

if its a brick wall (and youll know if you have the brick wall problem) theres a multitude of ways to diagnose, but id start by checking the connections to the secondaries. theyre up top and can easily be messed up, if one injector isnt working, both shut down.. so you could see how it could be that simple.

other than that you gotta search.
this info is for an s4, which i believe 88 is s4.

peace.

 

you defiiatly the secondaries ground the **** out of the engine

 

In the FAQ for FC it says that the 3800 rpm hesitation is a ground problem, i'm sure that the FAQ tells the truth. That'd be the first place i'd check, all the grounds. And major grounds as well, maybe try to add a ground between the engine and chasis and see if it improves any.

 

[QUOTE=rs_1101]blah blah..


if its a brick wall (and youll know if you have the brick wall problem) theres a multitude of ways to diagnose, but id start by checking the connections to the secondaries. theyre up top and can easily be messed up, if one injector isnt working, both shut down.. so you could see how it could be that simple.

other than that you gotta search.
this info is for an s4, which i believe 88 is s4.

peace.[/QUOTe

CRAP..that's right, I'd forgotten that happened to me . Secondary injectors got unplugged (I was messing with the wiring) and once I hit 3800, the car fell on it's face.

 

trust me, if you can screw it up, ive done it to my car. last time i had the UIM off, i didnt plug one of the primaries in right either..

but to reiterate, of your secondaries arent coming on, youll notice, youll literally fly forward when you hit 3800, the car slows down so much.
if its 5/6th ports, the car still accelerates normally,but not quite as fast.

 

My car ran great and pulled hard before I decided to rebuild the engine.

Found my 5/6 port rods stuck solid... the actuators work fine, I think... maybe I'm just not very good at blowing =p but they do "actuate" with some air pressure. The rods were all carbon'd up though and would barely move... broke one trying to remove them... they were pretty bad.

Anyway the point is, my car pulled strong and ran great... without 5/6 ports. So if anyone tells you there's a noticable difference they're lying... unless you drive it with and without, you'd never know.

--Gary

 

last time i saw a dyno there was a 15-20 hp difference between ports open and closed.