alright i figured out why my car was running so rich and stalling out. the filter in the ML was sucked down into the hole and was blocking the vac. as soon as i found that out and fixed it, runs great. and holy crap is driving it fun

how do i get the filter to stay in the missing link?

where did you get the filter for it. all the guys over at 2gnt say that the ML is crap and to go with the FCD that one of the users over there makes. im not really sure whats better

it came with a filter. but it seemed kinda small. they say that i could just use a cigarette filter and it should work. i guess i can try that

as far as the FCD... ive heard both are ok so who knows. may be a trial and error thing

the missing link tends to break over 15psi. the valve inside of it will pop out.

I never had a problem with it otherwise

ok so i went back out and did the missing link install step by step. turns out the valve on the inside was backwards and was creating a big vacuum leak. so i swtiched it around and put it back on. the car idled hard for about 15 secs then the idle dropped to about 400rpms and CEL came on. took it for a test drive and at 4000rpms hit fuel cut with the missing link in? so i went home and took it off and put the map sensor back in with out the ML. took it back out for a test drive and perfect boosting. the only thing i can think is that i can change the idle settings when i get the safc and have it work with the ML. pwee since i know you have sucessfully turboed your 420a with a missing link can you shed some light on whats going on?

it sounds like the valve wasn't backwards until you moved it. under vacuum it's supposed to leak like that, thats what the little filter is for. you need to pop that valve out again, spin it around, and then epoxy it in so it doesn't pop out under boost.

the missing link truly is a pain in the ass. I have a GM 2 BAR MAP sensor if you wanted to try that. You would have to add fuel with an AFC during idle but it would eliminate your fuel cut until you boosted more than 14.5psi.

yea I am def looking for an alternative for the fuel cut and map sensor. although my funds are very limited, pm me the price and we can talk

pmd

Pwee and i decided to talk about this in this post so the info is accessible to all

i was doing some looking on the internet about the 2 bar and i read that it could possibly advance the timing and cause a problem due to it reading the positive pressure being read by the ECU. how did you have it installed for it to work

ALL map sensors use a voltage range of 0-5v. Depending on the size of the sensor the voltage at a certain vacuum/boost will be different.
read here to get a good base: http://www.mitsubishi-forums.com/index.php...st&p=218493

This chart will help explain things also:
 3BARv2BAR_Map.gif ( 26.93K ) Number of downloads: 12


you can see how the voltage has a linear signal pattern from 0-5v that increases as vacuum decreases and boost increases. The OEM map sensor (1 bar) sends a near 5v signal at 0mm/hg or 0psi (when the car is off). This means that the 420a car is designed for vacuum only, which we already knew. When you are boosting the map sensor sees 0psi+ and sends an actual 5v signal. The ECU has no idea what happened because the car is supposed to run on vacuum and the signal is never supposed to get that high. So it panics and fuel cuts to protect itself.

In this list you can see the range each individual sensor has. All send 0-5v but send their signals over a broader range of pressures.
1 bar map - 30mm/hg to 0mm/hg
2 bar map - 30mm/hg to 14.5 psi
3 bar map - 30mm/hg to 29psi

** not actual values, just for example purposes**
Lets say at (15mm/hg) the OEM 1 bar sensor sends a 2.5v signal because at that vacuum its at half of its signal range. The 2 bar might send a 1.7v signal because at that vacuum its at a third of it's signal range. A 3 bar might send a 1.25 signal because its at a fourth of its signal range.

When you install a 2 or 3 bar map the ecu is still expecting a 1 bar map to send readings. Therefore, at a 15mm/hg idle the ecu is expecting 2.5v but instead gets 1.7v from the 2 bar. It thinks that you are idling at 20mm/hg (1 third of the oem map signal matching 1 third of the 2 bar map signal) and starts to lean out the mixture because it thinks less air is going into the engine and can stall the engine during cold starts or even at a stop light. Of course, you have to retune the entire rpm range as well to compensate for the larger sensor. But unless you exceed 14.5psi you won't fuel cut. The 3 bar sensor is harder to get right because its so much larger than the 1 bar oem map. You actually have to increase base fuel pressure and really spin up your afc settings to get it to run.

I know someone is going to ask, "doesn't adding all that fuel make the car run super rich?" It's a good question and the answer is no. You have to add fuel because the bigger map sensor is sending less of a signal than the oem map would. Therefore the ecu thinks there is less air going into the engine then there actually is. Less air, less fuel. So adding fuel on your afc is the only way to compensate for the ecu thinking it needs less fuel. But the afc can only go so far and if you cant get the a/f you want you need to increase fuel pressure.

There shouldn't be an issue of timing. Every ECU has a certain timing curve which fluxuates as you drive with different throttle positions, different RPM, etc. At WOT the ecu goes into open loop operation and the follows its preset WOT timing curve. This really doesn't have much to do with the MAP but more with the TPS. The ecu will see 100% from the tps regardless of what the map says and should follow its open loop directions. From 97-99 420a cars have a knock sensor. I don't know if the 95-96 cars do. If for some reason the timing gets wacky and causes knock, or your fuel settings cause knock the knock sensor will see it and pull timing out.

so because the ecu is still seeing a voltage less than 5v while in boost you can tune your afc for adding fuel while in boost?

am I understanding this correctly?

Yep you got it. If you exceed 14.5psi you will fuel cut though because thats the 5v max of the 2bar. Anything under that and your golden

ok kinda got a question. readin around what people seem to say is that you get big injectors and just lean it out with the afc but with this bar map thing you can add fuel as well?

Hey, I got a question, not to thread jack or anything...

But does this mean that even if we managed to squeeze 450 horse power out of an N/A 420A, we could still use the 1 bar MAP? Or is there a limit to it?

And as far as boost, didn't you say it's relative to the turbo? So if you had a Garrett GT6041 pushing 25 psi, it would measure the same as a Garrett GT2560R pushing 25 psi on that 3 bar map?

it's not that you "lean it out" with bigger injectors, its more that the injectors will flow more than oem at the same fuel pressure so you need to "control" their flow better. The AFC removes and adds fuel both, the MAP sensor has nothing to do with it.

the term "bar" is a meassure of pressure just like "psi." 1 bar = 14.5 psi. Map sensors are typically rated in bar's instead of psi.
1 bar map = -15psi to 0
2 bar map = -15psi to 14.5psi
3 bar map = -15psi to 29psi

so the afc keeps the fuel pressure stable or does the afpr or both

n/a is n/a and always uses vacuum. therefore, yes, you could use the oem 1 bar map sensor because it is suitable to read vacuum. It doesn't matter how much air you are drawing in an n/a engine there will always be vacuum.

Boost is a measure of pressue in psi. "Flow" is relative to turbos. So yes, 25psi on any map sensor is still 25psi no matter what turbo you're running. BUT with a bigger turbo you are flowing more so even though its still only 25psi you are pushing alot more air in there and need to watch your a/f's

the AFC only adjusts how much more, or less, the fuel injectors will deliver at the rpm settings you've entered. it has nothing to do with fuel pressure, the AFPR controls that.

oh ok that makes sense now. sorry to jack the thread

Your not jacking, I split it off so we could keep going with it (IMG:style_emoticons/default/smile.gif)