[nolife]

Reason i think i have a vac leak..
Any one of these things could be caused by any number of issues but added up, seems like a vac leak to me. Random surging idle, I have not pulled the plugs yet but the cats smell like sulpher at times which based on my reading, is an indication of a lean condition after a rich condition, Since I have boost, I assume a vac leak at low power would suck more air in making the mixture lean and under boost, push air out making it run rich. And possibly related to a bad lower man gasket is I get a puddle of coolant that collects on the top driver side of the water pump. That could be the water pump gasket or even the thermo gasket as well though but I can't see the source. Does coolant run around the lower manifold in that area?

Bottom line though..
I tried some carb cleaner/starter fluid all over and around my vac lines, anything with a vac line, and around the lower/upper manifold and found no leaks. How accurate is that test? I don't really want to pull the lower manifold off if I don't have too.

[flattusmaximus78]

How random is the surging idle? Try replaceing some of the vacuum lines. It's an easy start and doesn't cost much.

[nolife]

I have tons of them because everything is still on the car emissions wise but I did won;t hurt to do it again. The surging is pretty bad. About 50% of the time when I come to a stop, I have to ease off the gas or hold it at about 1000 for a few seconds first, basically, I got used to it and work around it. I've done just about everything else I can think of, like clean or adjust the tps, 10 pin connectors, MAS, IAB, throttle body etc. That and the other things are why I am now looking at maybe the lower manifold..

[88Saleen]

my car did the exact same thing to me about two years ago. i did the thermo gasket and nothing happened, i found it was the lower mani gasket leaking. idk where it comes from there, but it sure was coming from there. so my guess as for the coolant problem is just re gasket the manifold which you will get the thermostat gasket with the kit, along with the throttle body gaskets just for the added security that that is not whats leaking.

[grnstang]

be careful driving around with it running lean like that.

[flattusmaximus78]

I've tested the lean waters... my afrs are 12.2 at wot boost. needless to say I'm waiting for a retune. Just keep the lead out of your right foot.

[grnstang]

did you get your pillar pod yet? do you have 3 gauges to put in it?

[flattusmaximus78]

I'm at work actually. I totally forgot it was comming in ahhh I'm excited lol I can actually look at my wideband without holding it. I'll pm you when I get home. And no I don't have 3 to fill it, I'll get by.

[grnstang]

haha get on autometers site and get one of those shift lights with the digital read out of your RPM's 2 1/16 it will go in that pillar and look bad ass!!

[Mustang RacR94]

easiest way to find a vacuum leak is to take a propane torch, and spray a little bit of propane around the motor, a little at a time by were vacuum leaks can be. if the RPM suddenly goes up, you have yourself a vacuum leak in that area, and just spray the gas, not flame, and make sure theres no open spark or flame undre your hood, I take no responsibility if you somehow fuck doing this up

[Mustang RacR94]

Originally Posted by flattusmaximus78 I've tested the lean waters... my afrs are 12.2 at wot boost. needless to say I'm waiting for a retune. Just keep the lead out of your right foot.

12.2 isnt lean?? if thats what you were trying to say, thats pretty damn rich.

and some cars surge at idle due to low coolant and if your leaking it. ormaybe its a malfunctioning egr. theres alot of things that cause surging. and cats that smell like sulfur doesnt mean there going bad, alot of times it means there working

[flattusmaximus78]

Originally Posted by Mustang RacR94 12.2 isnt lean?? if thats what you were trying to say, thats pretty damn rich. and some cars surge at idle due to low coolant and if your leaking it. ormaybe its a malfunctioning egr. theres alot of things that cause surging. and cats that smell like sulfur doesnt mean there going bad, alot of times it means there working

The car is boosted. Thats lean.

[flattusmaximus78]

Originally Posted by grnstang haha get on autometers site and get one of those shift lights with the digital read out of your RPM's 2 1/16 it will go in that pillar and look bad ass!!

I need a tach so badddddddd We will see lol so pricy though. I need a smaller pulley, and some body work done, so it may wait.

[Mustang RacR94]

I see

[Smirnoff]

def sounds lke a vac leak... , and that puddle of coolant happened to me too when my mani gasket was bad

[flattusmaximus78]

If you don't feel like pulling the manifold off pressurize your cooling system while the car is off. Coolant or water will spill out of were ever the leak is.

[88Saleen]

Originally Posted by flattusmaximus78 If you don't feel like pulling the manifold off pressurize your cooling system while the car is off. Coolant or water will spill out of were ever the leak is.

+ 1 but i sure dont have the equipment to pressurize the system at my house, maybe he does tho

[flattusmaximus78]

I'm sure osmeone at a tires plus would do it for free. You just pull off the rad cap put this air pump on it, and starts building pressure in the system. It gets it to ideal pressure and if theres not leaks at the correct pressure then its fine, but in your case you clearly have a leak.... use this to find the source.

[MOTOIMPAIRED]

Originally Posted by flattusmaximus78 I need a tach so badddddddd We will see lol so pricy though. I need a smaller pulley, and some body work done, so it may wait.

I have a Autogage with a shift light sitting in the garage.. PM me if your interested..

[Hydration]

Mine was doing the same thing, I got rid of my EGR with a simulator for like 30 bucks on ebay and its idling fine now. Also if its when you're at a stop-check your brake booster, did you check your vacuum pressure? Couple things to look into..