Stalling at IDLE again w/ the MPI

[Bigg Tim]

Hmmm...looking at your map, I may have figured out my problem. I looked at your sensor calibration, and it looks like my AMP sensor scale calibration needs to have 5.0 volts in the max value instead of 3.8!

Cool!!!!(thumb) Glad I can help. I tried to change the amp column to be between X and Y boost, but it seems to work better the way I have it now. Chas does his the same if I remember correctly.

Also SMP, if you have any old vacuum lines that may be a little cracked and with them being removed they could of cracked more. After all, you are in that hot ass AZ heat. Have you tried the carb cleaner yet?

 

[smp3000]

hmmm thanks for all your help guys... I have had NO time to try and fix this sine Sturday morning- and it's still not fixed... I actually rant he car at the track (yeah I know I'm stupid) on sat night even with these idle issues and a wacky MPI map loaded. I ran a slow ass time (15.7) because my A/f's were crap and heard deton so I was forced to shift early.

I just got home from a trip up north and plan on taking a look at a few of these htings tomorrow morning. I swear I've already traced every vacuum line and haven't found a leak yet. There aer however a few vacuum hoses which aren't needed and I have temporarily plugged entil I can get a plug up top the signal source fitting. What exactly do you mean by using carb cleaner Tim?

Another possibility is the O2 sensor that Protege5Gurly mentioned. I haven't tapped into it but did add the MIL eliminator and should probably check those wires to make sue nothing came loose. Which O2 is that- the first or second?

Right now I'm mad rich at idle. It starts at 11's then goes to low 12's and sometiems so rich it's off the charts. My map is setup just like Chas's with 6's in that column at 0 fuel cal.

One thing I messed wit (and shoulnd't have) was the idle screw. I'm hoping I didn't mess it up and maybe that's the cause. It there anyway to reset it? Or know how to get it back to where it should be?

 

[KzA]

the only way your gonna fix the idle screw is snippin the power wire to the MPI, starting the car on the stock ecu and putting the idle back to where it was..

 

[smp3000]

hmmm... Well...

A. How do I know where it was. B. Why would I need to cut the power wire to the MPI?

I'll check all of the other things before I go to that measure. Hopefully I can have this fixed tomorrow night. It sucks stalling at every stoplight!

 

[TurfBurn]

He means that you need to disable the MPI and then set the idle for the car running off it's own ECU. Then after that you can reconnect the MPI.

You put the MIL on the second O2 right? if you put it on the first that could cause your problems as well.

Later!

Steve

 

[Bigg Tim]

What exactly do you mean by using carb cleaner Tim?

Turn on the car and let it idle. Then take the carb cleaner and spray around the couplings and/or vacuum lines and and if the idle raises, then theres a leak. Do one at a time so you know which line is good and which is bad.

 

[LinuxRacr]

Does carb/brake cleaner cause the hoses and couplings to slip off?

 

[hazeXban]

Doesn't 11 then 12 then off the charts mean LEAN? I thought lower numbers meant rich, Air/Fuel am I wrong or right on this...

 

[LinuxRacr]

On cold startups, your idle A/F ratio will dip as low as 12's STOCK before the warmup. You need more fuel during cold startups.

 

[Bigg Tim]

Does carb/brake cleaner cause the hoses and couplings to slip off?

DO NOT USE BRAKE CLEANER!!!! Carb cleaner is the thing to use. If the couplings are on tight, they will not come off. That's the whole reason to use it, if there is air or carb cleaner getting in under the coupling or vacuum line, then that's the leak and needs to be addressed. The carb cleaner evaporates/dries pretty quick, so there's nothing to worry about there.

 

[LinuxRacr]

Ok, I see! The break cleaner is only good for testing for liquid leaks due to its thin nature.

 

[acidbug]

Doesn't 11 then 12 then off the charts mean LEAN? I thought lower numbers meant rich, Air/Fuel am I wrong or right on this...

11's & 12's are perfect for in boost situations..but at idle...you don't wanna be very rich.

Chas

 

[smp3000]

Turn on the car and let it idle. Then take the carb cleaner and spray around the couplings and/or vacuum lines and and if the idle raises, then theres a leak. Do one at a time so you know which line is good and which is bad.

The idle will raise as I spray the bad lines? Why is this? Will it be temporarily clogging the holes?

 

[smp3000]

Another thing about the idle screw- Since the MPI is installed woudln't it not make any difference to the idle no matter what I did to the idle screw?

I just don't see how it's possible to adjust the idle screw- and then not be able to adjust it back unless I disconnect the MPI.

 

[hazeXban]

So lower numbers ie 10,9 are meaning that you are Rich correct, and 11, 12, 13 are leaner numbers. I am just trying to make sure I am right, cause this is Air/Fuel, so smaller numbers on bottom equals larger total number in the fraction, simple math hehe.

 

[blynzoo]

The idle will raise as I spray the bad lines? Why is this? Will it be temporarily clogging the holes?

Idle will be around 600 stock.
I, too, think it is a vacuum leak. Can you try slowly letting off the accelerator in neutral (i.e. not just quickly removing your foot?) If it does not stall then, it is definitely a vacuum leak.

Oh, and to quote Chas..." How far is your bov from the MAF?"

 

[smp3000]

Yes, if I tender the accelerator usually it won't die at all. It will just stick real low around 400 or so, but if I go from foot on gas to no foot on gas really fast forget it- stall....

My BOV is pretty far from my MAF. Like 2 feet horiz and 1.5 feet down.

 

[KzA]

Another thing about the idle screw- Since the MPI is installed woudln't it not make any difference to the idle no matter what I did to the idle screw?

I just don't see how it's possible to adjust the idle screw- and then not be able to adjust it back unless I disconnect the MPI.

ok...the mpi is altering your idle, not TOTALLY controlling it. Therefor, the idle you see now is a combination of the engines idle(controlled by the screw) and the MPIs effect on idle(controlled by your map)..

In order to get the idle back to what it originally was stock, you would have to disconnect the MPI, so the only thing effecting your idle would be the idle screw. Then, you can adjust the idle back to where it was STOCK with only the screw and the STOCK ECU controlling it..Get me? Once thats done you can rehook the MPI and tune from there..

I'm not sure if this is even necessary tho, but thats how you would get the idle screw back to its original position.

 

[acidbug]

That sucks dude..u should have marked the stock location.

Good luck fixing the idle situation.

Chas

 

[LinuxRacr]

I just recently adjusted my idle with the MPI hooked up.