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Topic: A/C killing the engine, except... (Read 1012 times) previous topic - next topic

A/C killing the engine, except...

Whenever I turn on the A/C in my 86 Cougar 5.0, it kills the engine.  I've never tried while driving, for fear of death...  but I noticed the other day that if i turn on the defrost with the temp all the way on cold, it will blow nice cold air out through the defroster.  Any idea's?

A/C killing the engine, except...

Reply #1
Idle might be low.
88 Cougar LS 5.0 .030 over, ported E7s with GT40 valves & trickflow springs, Proform roller rockers, HO cam, removed air silencer, K&N filter, smog pump delete, 2.25" dual flowmasters, Pacestter H-pipe & headers, HO computer, 65mm TB, Explorer intake, 19# injecters, 3.45s, rebuilt posi, and TCI shift kit.


A/C killing the engine, except...

Reply #3
i'm thinking so.  tried turning it on while driving tonight, and it ran fine, even when i came to a stop.  once i got home to my driveway, i put it in park and it stayed running.  was even able to pop the hood and look at what's going on underneath.  i had to replace the IAC not too long ago.  how do i go about raising my idle?


 

A/C killing the engine, except...

Reply #5
that fixed it.  thanks guys!  never saw that screw all the other times i tried to look for it...

A/C killing the engine, except...

Reply #6
The idle is not set with that SCREW. That screw is a MIN idle screw that balances out the TPS and MIN idle speed. The IAC controls the idle on that engine. Their is a Procedure to adjust that in the service manual. May i suggest doing it by the BOOK. Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

A/C killing the engine, except...

Reply #7
I bumped my idle speed up with that screw and then checked my TPS voltage and brought it down to .98 volts.  Not sure if that is the correct way or not?
Mike

A/C killing the engine, except...

Reply #8
That works GOOD enough. Because if the tps goes out of range the idle can FLAIR UP quite high. Good job!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!