Vacuum leak or IAC?

JAFO

Registered User
Twice in the last few days I've started the car and it barely wants to run. Vacuum stumbles around 12, runs like it wants to die. This is at idle, at startup, once when cold, once when warm. Touch the gas and it revs and levels out as normal, vacuum at about 19. When driving, in gear, off gas slowing down vacuum is about 24. If that helps at all. :confused:

I swapped out the brake accumulator the other day, which means I pulled a bit on the lines running over that. I know I pulled to lines out, which I put back on, not sure what to call them to distinguish them. So, I'm wondering if there's another that I didn't see, or maybe the IAC is going out? Where should I check for the vacuum leaks that I may have missed?

BTW, what does a new IAC run?


Thanks, I know this is the 1001'st IAC post, but I didn't find just what I needed in a search.
 
JAFO said:
Twice in the last few days I've started the car and it barely wants to run. Vacuum stumbles around 12, runs like it wants to die. This is at idle, at startup, once when cold, once when warm. Touch the gas and it revs and levels out as normal, vacuum at about 19. When driving, in gear, off gas slowing down vacuum is about 24. If that helps at all. :confused:

I swapped out the brake accumulator the other day, which means I pulled a bit on the lines running over that. I know I pulled to lines out, which I put back on, not sure what to call them to distinguish them. So, I'm wondering if there's another that I didn't see, or maybe the IAC is going out? Where should I check for the vacuum leaks that I may have missed?

BTW, what does a new IAC run? Just bought a new IAC for my 92 SC last week $100.00, if you plug the one out that you have and engine dies, still could be IAC, but more likely a vacum leak...I learned this the hard way.


Thanks, I know this is the 1001'st IAC post, but I didn't find just what I needed in a search.

Just bought a new IAC for my 92 SC last week $100.00, if you plug the one out that you have and engine dies, still could be IAC, but more likely a vacum leak...I learned this the hard way.
 
Charles G said:
Just bought a new IAC for my 92 SC last week $100.00, if you plug the one out that you have and engine dies, still could be IAC, but more likely a vacum leak...I learned this the hard way.
A good way to find a vac leak is to spray ether IN SMALL AMOUNTS around the supspected area. If the motor revs up, you found it.
 
i kinda doubt its iac mine has 220 k miles and still stock iac in all my years working on cars ( more than 25 yrs) , which i do every day except the lord s day ive only replaced very few iacs (prob less than 5) , if battery was unhooked it may take 3 days or 200 miles of driving to go away
 
Last edited:
Back
Top