Vacuum Leak After Transmission Rebuild

diablopony · 06-14-2001, 08:48 PM

I just had my C-4 rebuilt at what I thought was a very reputable shop and it came back running like crap. Also, the power brakes aren't working. I know they somehow screwed up the vacuum hoses, but I can't seem to find it.

My manifold has 1 vacuum outlet that splits for both the transmission and power brakes. Everything looks tight and the hoses are connected well. Any ideas on how to find this leak?

Dark Knight · 06-14-2001, 10:28 PM

check where the Vac line plugs into the tranny, it might be off...if you spray WD-40
around, the idle will pick up when you find the leak

------------------
84 convt,'95 302,AFR's, performer
3.55's, underdrives stock shorties
stock cam, 1.7's
14.06@100.21, 255RWHP on a hot day
265 on the mph/weight chart

Gearhead999 · 06-16-2001, 07:26 AM

Do what Dark Knight says and also try pinching the hoses coming off the "T" and see if it fixes the idle problem.

Could also be a bad vacumn modulator

diablopony · 06-17-2001, 10:23 AM

I'm pretty sure I know what the problem is and I'm not very happy about it. I plug the vacuum line to the brake power booster and the car idles fine. A little over a year ago I replaced the brake power booster. It had (operative word) a 1 year warrenty.

This time I'm not going the Kragen route. I'll spend a few more $$s and get a good one. Lesson learned!

Gearhead999 · 06-17-2001, 07:15 PM

Call Booster Dewey. I have installed 6 or so of his rebuilds without a problem. Easy to deal with too.

06-14-2001, 08:48 PM	#1
diablopony Registered Member Join Date: Jan 2001 Location: Clayton, CA USA Posts: 116	Vacuum Leak After Transmission Rebuild I just had my C-4 rebuilt at what I thought was a very reputable shop and it came back running like crap. Also, the power brakes aren't working. I know they somehow screwed up the vacuum hoses, but I can't seem to find it. My manifold has 1 vacuum outlet that splits for both the transmission and power brakes. Everything looks tight and the hoses are connected well. Any ideas on how to find this leak?

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06-14-2001, 10:28 PM	#2
Dark Knight Registered Member Join Date: Oct 1998 Location: Az Posts: 854	check where the Vac line plugs into the tranny, it might be off...if you spray WD-40 around, the idle will pick up when you find the leak ------------------ 84 convt,'95 302,AFR's, performer 3.55's, underdrives stock shorties stock cam, 1.7's 14.06@100.21, 255RWHP on a hot day 265 on the mph/weight chart

06-16-2001, 07:26 AM	#3
Gearhead999 Registered Member Join Date: Sep 1998 Location: Oviedo, FL Posts: 992	Do what Dark Knight says and also try pinching the hoses coming off the "T" and see if it fixes the idle problem. Could also be a bad vacumn modulator

06-17-2001, 10:23 AM	#4
diablopony Registered Member Join Date: Jan 2001 Location: Clayton, CA USA Posts: 116	I'm pretty sure I know what the problem is and I'm not very happy about it. I plug the vacuum line to the brake power booster and the car idles fine. A little over a year ago I replaced the brake power booster. It had (operative word) a 1 year warrenty. This time I'm not going the Kragen route. I'll spend a few more $$s and get a good one. Lesson learned!

06-17-2001, 07:15 PM	#5
Gearhead999 Registered Member Join Date: Sep 1998 Location: Oviedo, FL Posts: 992	Call Booster Dewey. I have installed 6 or so of his rebuilds without a problem. Easy to deal with too.