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These are installation Procedures for eliminating the boost vacuum leak in the Dart. There is NO check valve which means that this a direct boost leak. This is the reason for laggy boost and boost dropping off on the top end. This HOW TO is compliments of Blitzkrieg as being the first author to post about this solution and also to Blitzkrieg, SF18C, and mackzilla for pictures of their setups. If anyone attempts this and cares to upload pictures for each step or cares to elaborate on the steps in more detail, we will add them as we go along.

1. Remove the cover off the engine and take a look at the charge pipe on the Driver's side.
2. After removal of the turbo cover, you should see the MAF sensor and the 3/8" vacuum line just prior to it. If you follow this line you will see that it goes to a Tee. One side goes to the intake manifold (I believe) and the other goes to the intake just prior to the turbo.
3. Remove the hose on the charge pipe (driver's side).
4. Place a rubber/plastic cap on the tube then placed the hose back on it. This effectively blocks off the flow.

***In the words of Blitzkrieg, "Now there is more TQ down low with a quicker spool and more HP up top with no boost leaks."
He also checked the Abarth and there IS a check valve in place. No check engine lights or issues have been reported since making this change.

Here are a few different setups of the same solution.

Auto part Exhaust manifold Engine Fuel line Vehicle
Auto part Engine Vehicle Car Automotive engine part
Auto part Vehicle Engine Car Automotive engine part
 

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I'd contribute if I knew more, and I thank you for your post, however I find this to be lacking a good bit of detail - to the point where, as a lay person, I wouldn't feel comfortable making this modification.

I'd like to request of those who have performed this modification, more detailed part (what did you and others use) and procedure steps, clarification of acronyms, and if at all possible (being hopeful) annotated graphics showing what attaches where.

Currently the instructions state that one must remove the turbo cover, is this a typo? If so where is the turbo cover? Is it true that you cap the valve and then place the valve over what has been capped? and what parts are best to cap it with? Any more information would be appreciated. Thanks!
 

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i have come to the realization that i may not get to testing/logging the results of this mod for several months. in the interim, i will try to explain the system being modified, the purpose of this "leak" and any possible side effects.

the system being modified is the evaporative emissions system. as fuel in the tank evaporates, fuel vapours are stored in the charcoal canister, to be burned during normal engine operation.

normally, vacuum in the intake manifold will draw these vapours from the canister, through a PPS (proportional purge solenoid) valve which is PCM controlled.
since forced induction (turbo) creates a pressure situation inside the intake manifold, normal canister purging cannot take place while the system is under boost.
a special system was developed in order to allow purge flow under boost. the system consists of special hose routing, check valves and a vent valve.

when the intake manifold is under vacuum, the purge flow is directed from the PPS through a check valve, into the intake manifold.
when the manifold is under boost, the purge vapours cannot flow into the intake manifold. instead, purge flow is directed to the air intake area upstream of the turbo inlet.
this is done through a bypass hose routed from the intake tube near the throttle body (boost) to the area upstream of the turbo (vacuum).
the ejector tee is a venturi that draws vapours through a check valve.





blocking the bypass hose, which is what this mod essentially does, will prevent purge flow during boost.
i'm surprised this mod hasn't set any DTCs as purge vapours are monitored by the PCM by verifying the short term fuel trim shift while PPS is active. since there will be no purge during boost, there will be no fuel trim shift. i would have thought the PCM would recognize that and set a DTC. anyone who's done this mod needs to post any DTCs, even if they don't seem related, so we can keep track of possible trends.

i know it's difficult to argue against butt dyno results but as i see it, any possible gains would be negligible since the PCM will always control boost, based on the sensed boost pressure, by actuating the wastegate. haven't looked into how this would affect surge valve operation, if at all.
i would be interested in actual dyno results (before/after). if someone could post that up, it would benefit everyone.

as for long term side effects, none that i can see, unless the vehicle is always under boost. in which case, the canister may become saturated.
 

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The really scary thing about what you just wrote out Funky...I actually understand it LOL. I've never owned a boosted car before but having read what you just posted, it makes a lot of sense to me and I actually have an understanding or the airflow through the engine now under both normal driving (vaccuum) and also under high throttle (boost). Thank you Sir...
 

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i have 5200 miles on my car now and did this mod when i had 350 miles on it,

this weekend i got a check engine light and so i removed the plug,

when i had my charger i was able to cycle the key and get a code can i do that with the dart,

also if the canister is saturated how long will it take to purge and the check engine lite to go off
 

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i have 5200 miles on my car now and did this mod when i had 350 miles on it,

this weekend i got a check engine light and so i removed the plug,

when i had my charger i was able to cycle the key and get a code can i do that with the dart,

also if the canister is saturated how long will it take to purge and the check engine lite to go off
it would be best to get it scanned. not sure if the key dance works on the dart. try it and see. once canister is saturated, it usually needs to be replaced.
 

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it would be best to get it scanned. not sure if the key dance works on the dart. try it and see. once canister is saturated, it usually needs to be replaced.
i dont have a dealer near by so i would have to take a day off and sit there, would the engine eventually pull all the fumes out from driving a while since the motor is supposed to suck the air from it, and what damage would i do to my car by driving like this for a while
 

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So.. this is a mod that should not be done in favor of PCM malfunction, or throwing codes?
not enought empirical data yet to say either way.

i dont have a dealer near by so i would have to take a day off and sit there, would the engine eventually pull all the fumes out from driving a while since the motor is supposed to suck the air from it, and what damage would i do to my car by driving like this for a while
since we're not even sure that the canister has anything to do with your MIL illumination, it's kinda hrd to say whether you should drive it or not.

My question is. Do all the after market intakes block this off? I don't like the idea of replacing the canister every so often just to get some HP.
no idea on the aftermarket intakes. no proof yet about the canister.
 

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the check engine light went off yesterday so i figure all is well now and whatever made it happen is OK, so regardless of what made the light go on and off i am going to leave the plug off, since the code went out after i removed the plug i am only going by logic since it went out after i drove a couple of hundred miles with the plug off, i really don't feel much of a difference with it off, what i do wish is that the stuttering that happens at times when accelerating would stop
 

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.. maybe it was messing with the air-fuel ratio. The Stuttering is going to be fixed by a ECU flash iirc, TSB. The only reason my car (passat) stutters under boost, is no/low spark (dying coilpacks in my case)
 

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.. maybe it was messing with the air-fuel ratio. The Stuttering is going to be fixed by a ECU flash iirc, TSB. The only reason my car (passat) stutters under boost, is no/low spark (dying coilpacks in my case)
do you know if there is a TSB for 1.4 with the manual, it seems like i am not the only one with the issue and this mod was one of the reasons people did it, thanks
 

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i dont have a dealer near by so i would have to take a day off and sit there, would the engine eventually pull all the fumes out from driving a while since the motor is supposed to suck the air from it, and what damage would i do to my car by driving like this for a while
Honestly, without looking at your car in-depth and just going by what you said in this thread... I would say it is most likely that your cap became loose and caused a slight boost leak which has been known to throw codes. see this thread: http://www.dodge-dart.org/forum/dodge-dart-1-4l-multiair-turbo/1437-cel-help.html The CEL code is still in the computer, so you should be able to read it still and see if it matches up. I put about 1000-1500 miles on with the mod before I took it off. Honestly, it's not worth it... perhaps if you put a check valve on then it would be better since it would still function one way.

My question is. Do all the after market intakes block this off? I don't like the idea of replacing the canister every so often just to get some HP.
Don't quote me but, as far as I know, the intakes that mess with this at all should be check valved so that it allows the evap system to function normal but restricting air flow one direction so the boost can't bleed back.

Just so you know, "just to get some HP" is incorrect. You gain absolutely no horsepower by performing this mod, and only get a slightly larger powerband from the turbo (its more responsive at like 3-400 rpms lower).
 
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