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Topic: Pop quiz time! (Read 1325 times) previous topic - next topic

Pop quiz time!

Winner gets a free piece of candy of their choosing.  I won't ship it so you'll have to come and get it :hick:

Anyway... What is the circled part and what is it's purpose?
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Pop quiz time!

Reply #1
It's the exhaust heat control valve.

It opens when the engine is cold to heat up the manifold and incoming air for better vaporization.
It helps drivability/emissions before the engine is warmed up.

Pop quiz time!

Reply #2
and,,,,,,,Ill bet your  posting this because you can hear it chatter at different time of "decreased" throttle:D

Pop quiz time!

Reply #3
since we are on the topic of that.... whats the best way to remove it and stop it from working :-?

Pop quiz time!

Reply #4
Quote from: the_intimidator03;204533
since we are on the topic of that.... whats the best way to remove it and stop it from working :-?


BFH... Probably the only tool I'd ever use on a Ford 3.8...

Pop quiz time!

Reply #5
its actually two pieces.  the vac actuator can come off with a BFH but the valve itself is pressed in from the top i think.

Pop quiz time!

Reply #6
Quote from: jcassity;204526
and,,,,,,,Ill bet your  posting this because you can hear it chatter at different time of "decreased" throttle:D


Actually I'm posting it because with an engine vacuum line connected to it, my engine seems to run better.  Otherwise it runs rich and sputters at low RPM.  The butterfly valve thing on the exhaust manifold isn't even connected as it is shown in the EVTM. 

Yep, I'm still searching for problems so I can fix whatever is causing a rich condition.  I did try to run the codes, bought a code reader and everything, but I couldn't retrieve any codes.  I'm getting 10 mpg in town and really getting tired of spending 40 bucks a week on gas.  I was hoping you'd tell me this thing was supposed to be connected to the vacuum system and I'd just overlooked it when swapping throttle bodies.  This is not the case, is it?
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Pop quiz time!

Reply #7
you lost me.

whats your setup now.

exactly what CFI, as in,,,,,,,,,describe its style ect cause there are three that i am aware of.



 and exactly what color injector

Pop quiz time!

Reply #8
I have the v8 throttle body installed with the original v6 injectors.  I have the problem figured out so this thread has become a moot point.  It was the ACT sensor messing up.  The computer didn't know whether or not the engine was warmed up, so it was supplying more fuel than necessary.  Which might explain why opening the heat control valve made it run better.  Does this make sense or is my logic flawed?
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

Pop quiz time!

Reply #9
sounds good to me.  your darn lucky the thing ran at all with a bad act.  Mine would not start with the act unhooked (simulated open).

Did you notice a difference using the larger TB?

Pop quiz time!

Reply #10
I have been running the larger TB since I first read your write up on it a couple years ago.  I could tell there was marked improvement in throttle response.  Pulling the screens out of the injectors also fixed the annoying little hesitation problem that existed from the beginning.  Tomorrow I have to investigate the TPS, as that was another code being thrown.  I do have one I can swap out, so we'll how that goes.  Which reminds me!  I have been using the TPS from the v8 TB from the start.  Maybe if the parts are different specs for different engines it could indicate why I'm getting the code.
1987 Thunderbird 3.8. Sold :(

1982 Thunderbird - Goodbye 255, Hello 302!

 

Pop quiz time!

Reply #11
wow, thread from the dead,,,
Im glad i convinced someone that those screens are the real root to hesitation.  good to hear though anyway.

no, specs are the same on pretty much any tps you run across in any car.

they all operate the same and no difference for the 4/6/8 cyl.

THere are differences however on the voltage found at the center tap of the variable resistor though with respect to GM which i know from experience. 

A lesson for you so you dont learn the hard way.  Test all variable resistors (ie-tps) with a cheapy buttstuffoge meter.  The needle will sweep as you check the resistance or volage at the green wire.  If the needle flickers as you move the trottle linkage ***VERY*** slowly, then there is an intermittant issue with the tps and it needs tossed.

Before you toss it,, bust it open and see whats inside and you will discover the tinly little wiper arm that rubs a plastic laminate with a carbon strip. 

Usually all TPS's get a wear spot right around where 50mph would generally be while in over drive,, ie- the place where the tps usually rubs the most.

also, to get the tps to read .7vdc on the green wire, use a chainsaw file to oblong the mounting holes out so that when you install it, you can then dial in the voltage value.

My tps on my H0 is so pen 15eyed , its easy to see at a glance.  Oh well, thats what it took to get the voltage i wanted.