Stalling at IDLE again w/ the MPI

[TurfBurn]

right, but in theory advancing the timing under low rpm and in "non" boost states would raise the idle right?

That is correct.

This is a silly one... but check it anyway in case the place messed up during the install on your car... make sure the MAF isn't pointed backwards... I would think you would have more problems... but it is a simple check at the least! Also try to verify that the vacuum hoses are going to the right locations as well... not that they are just not leaking.

Really hope you get it straightened out soon!

Later.

Steve

 

[smp3000]

This morning I traced all the vac lines and took them off to inspect them. All look fine and all are going to the right places.

Tonight if the porblem persists, I'm going to solder the mil fix on (as right now it's just using connectors), and change out the plugs. After that I'm clueless as to what it could be.

 

[acidbug]

I remember one time..i had the exact same problem..as you are having. turned out that one of my vaccum t's had cracked. when i went to check it out/remove it..it snapped into 2 pieces. I replaced it and my problem was fixed.

Chas

 

[smp3000]

hmmm Damn.... It sure does sound like a vacuum/air problem though doesn't it?

 

[acidbug]

hmmm Damn.... It sure does sound like a vacuum/air problem though doesn't it?

Yeah it def does. I can't tell you how many times i have had this same issue..you are describing. And every time it turned out to be a vaccum leak. And not the mpi tuner.

And idle would be ****** up. Would stall after i start the car. Or would run rich after i put it into neutral..and would stall.(shocked)

I tried the car cleaner trick. And it never worked for me. I just pulled all the pipes off..and check the silicone adapters..and vaccum lines. One time..the clamp cut the silicone adapter...And i couldn't tell until i actually pulled off the pipe.

Chas

 

[smp3000]

hmmm good idea- I'll take off my intake and charger pipes and check the silicon there.

 

[acidbug]

Also..if possible..check the ic core itself. I remember one member on here. Has/Had a hole in the ic..very small. And it caused him stalling issues.

I believe it was 1sty.

-Chas

 

[smp3000]

hmmmm the IC core eh? You mean check for holes in the pipes? Or the End tanks? I dont' know how I'd check the core.

 

[acidbug]

hmmmm the IC core eh? You mean check for holes in the pipes? Or the End tanks? I dont' know how I'd check the core.

Well that's the thing about having a FMIC. When you are driving down the road..if a car spits up a rock..on the highway..if it hits the ic..it can punture the core itself.

The best way to test..is to remove the IC..and fillit up w/ water & food coloring..if it leaks..you have a problem. But you can visually inspect the core. Just look for mangled fins..or lacerations.

Chas

 

[smp3000]

Well I know I have some mangled fins but nothing too crazy. the mangled fins would cause a leak? (sorry for my questions)

 

[blynzoo]

hmmmm the IC core eh? You mean check for holes in the pipes? Or the End tanks? I dont' know how I'd check the core.

It's visual, and takes time, or you can cap one and and put compressed air into the other and check for leaks.
To check for light leaks, you can use soapy water (lots of soap). Cover the part in soapy water, send in compressed air, look for bubbles.

 

[blynzoo]

Well that's the thing about having a FMIC. When you are driving down the road..if a car spits up a rock..on the highway..if it hits the ic..it can punture the core itself.

The best way to test..is to remove the IC..and fillit up w/ water & food coloring..if it leaks..you have a problem. But you can visually inspect the core. Just look for mangled fins..or lacerations.

Chas

Or fill it up!

Never tried that, but it sounds like it would work. Cool idea. I am just skeptical about leaving the residue of anything in my intake piping.

 

[smp3000]

Wow, you guys rock!! thanks for all the advice. I'll check everything hopefully tonight and let you know what I find!!!

 

[acidbug]

Not exactly. But it might be a sign of where some potential damage might/could be.

I am just trying to help you trouble shoot the issue...I am sure this is a pain in the ass.

Chas

 

[smp3000]

s*** guys... Still nothing. Spent 3 hours tonight taking all the IC pipes off and checking the silicon couplers. Found nothing and put everything on back and tight. Then I even tightened my signal source fittings and re-traced every vacuum line. Car still stalls.

I'm going to do a quick check of all the MPI-ECU connections in the morning and then change out the plugs from BKR7's to VFR7's and see what that does.

I still have a small feeling that it's the idle screw. I hate how you have to unplug the IAC valve and then mess witht he screw and then start your car for it to take effect AND then plug it back in... NEVER have I had this work. My car will never start after I unplug the IAC valve- so who knows if anyhting has ever taken effect... But I do have a P0505 CEL which means it dedected my latest idle screw change...

I know that turning it counter clockwise is supposed to raise the idle, but what does this mean? Is it making it run more rich as you turn it counter clockwise or more lean? This could be the prob. Because when the car is running if I pop it into neutral and take my foot off the gas the rpms shoot down the AF's go off the charts rich and it dies.

 

[smp3000]

BTW Steve wat do you mean check if they put the MAF in backwards?

 

[TurfBurn]

The MAF is made to operate in one direction... sometimes people will put it in the opposite direction. I don't have a MAF to even look at so It's hard for me to be able to describe which end is which, but one end needs to go toward the intake, and the other toward the manifold. If they put that in backwards somehow such that the mani side is now pointed toward the intake it will mess up the flow readings and cause a lot of strange things to happen.

 

[smp3000]

hmmm I figured out which was was right and it's on there fine... I'm thinking it's the stupid idle screw or a leak in the IC itself. Have to take the bumper off to test the IC... I'm just trying to figure out what the deal is witht he idle screw.. Counter clockwise = more rich or more lean?

There's also a possibility my IAC valve is bad. I priced those out at the mazda dealer- 500 bucks!!!! you could buy a used engine for that!

 

[TurfBurn]

which valve is the IAC valve (aka picture/location)? I may have an extra one or two I have two full engines and valve sets at this point LOL

 

[smp3000]

ahaha The IAC valve is right above the throttle body. I tried taking it out once to clean but it's a little hard to get to. If you can, check the online shop manual for pictures and locations http://protege5.ugly.net/#ENG