so i have a 500whp monster 2nd gen i was driving today and i pulled out on the road and floored it and saw a huge cloud of smoke, so i immediately pulled over and looked under the hood to find anti freeze EVERYWHERE! i tracked down the leak and it was the heater hose that is near the drivers side fire wall that goes to rear plate from heater core, it split wide open and dumped all the coolant out, so i put a new hose on and the car runs strong still, and dosent leak but my idle is screwed up, im only pulling 15 on vacuum and it wont stay running due to very low idle, i looked for obvious vacuum leaks but didnt find any, havent checked all of them yet though..any other ideas of whats going on with this thing?

 

Nick,

You should pressure test your intake track for leaks. Just hook up compressor air with a regulator, you will need an adapter of some sorts..

 

I looked again today and can not find ANY vacuum leaks..im pissed..I even pulled the plugs and did the poor mans compression test and i have 3 strong pulses on each rotor..
I had a car cruise/meet today so i bumped the idle up and it ran good, still only pulling between 11 and 15 on vacuum gauge even with idle raised..so i drove the car for a total of 6 hours today and it ran perfect, still the same amount of power as always, its just not making vacuum??? i dont get it..i also should be able to hear the leak but there is nothing. Im lost.
Elliot, are you saying it could have an intake leak? like one of the gaskets? where do i hook up an air compressor? also do ya think i should get a can of starting fluid and spray around intake to listen for the engine to rev, indicating a vacuum leak?

EDIT: why would this happen at the same time the heater hose blew? i guess just a coincidence..

 

prolly but if i was you going to rx7sotre.net and you can buy the 5/8th line of silicone hoses for heater and never have a problem again with blowing hoses
TwEaK

 

I would try the starting fluid and use the whole can... sure nothing popped off...

+1 on the silicone hoses

 

I have an Idea.
If your Heater hose exploded,it could have got your TPS all WET.Coolant is a beotch, and can screw up anything electrical.
Check the TPS to see if the thing is in Spec.

 

ok so today i drove the car and it still had low vacuum but i had the idle bumped up and it made it run ok, but one minute the car would be driving perfect then next sec it would be breaking up very bad and i couldn't give it any throttle, but listen to this...lol i would hit a bump in the road and it would stop breaking up and it would run good again but still have the vacuum issue..and it did the breaking up thing a bunch of times, each time i would jus have to hit a bump to get the car running right lol so i guess a loose wire??

 

yup sounds like electrical

 

Do a real compression test just to get it out of the way. You would be surprised the intake leaks you can have @ 20psi of boost. Doing the test will help regardless. Starting fluid trick would be a good start. Not real sure what you're issue is, going to require some time to check everything...

 

The heater hose usually breaks due to oil leaking past broken oil filter pedestal o-rings. You may want to replace them just in case. It's only about $10 for two of them, and the job is really easy.

 

Isn't there anything we can use to just cover the hose and prevent oil from getting on it too as an extra precaution aside from changing it every coolant flush?

 

Sure, you can cover it with a dress-up sleeve or even aluminum foil, or you can replace it with an oil-resistant hose. However, that still doesn't fix the leak at the oil filter pedestal.

 

I said that with the assumption of pedestal leak being fixed already of course. =D

 

elliot, i actually dont have a compression tester other wise it would have been tested already..im gonna try and borrow one of the standard piston types because no one around here has a rotary comp tester..also im going to try the starting fluid thing..but im sure that it isnt the upper intake gasket because i replaced that fast and put the intake back on and it still ran like crap...

 

what engine management are you using?

 

Where is this silicone heater hose you refer to? I dont see it on the site... I see the silicone radiator hose, but not heater hose

 

That will work just fine.. Above 17psi I usually drill and tap all the vacuum ports for barbed fittings; something you might want to look into..

 

heres a link its 5/8 silicone hose for turbo oil return lines but can be used as heater hoses as there the same size
TwEaK

http://www.aptuning.net/ProductDetai...2D024&CartID=4

 

Bingo.

B