Car stalling

[slow5.0gt]

Hello i dont know if anyone else has come across symptons like this but if you have let me know what you did to correct them.
ever since I got the new computer hooked up the car wont stay on unless its warmed up any cold starts it takes lots of revs to keep it going till it warmed up would that be a problem with the MAF going bad?

New distrubtor so i ruled out the PIP module and then after that it idles at about 600 and sounds like its misfiring and when I drive if im in neutral and braking the lights dim and the car feels like it wants to turn off only when the rpms are below 1000 like at idle.

I feel the brake pedal stiffen up and the lights and everything electrical drops very low on my guages like its about to stall out when im moving.Im wondering if my ignition is no longer up to the task of supplying the voltage to my spark plugs and distrubtor. I have the stock coil since my MSD one went bad with my hunt to find out why my car wouldnt start. As long as the rpms are over 600 the car runs like a champ and wont give me any problems at all.


Anyone have any idea what could be causing this problem?

 

[Mr. Rustypwnz]

unplug the maf, then start the car up if it idles fine, does normal, its that, or something related to that. Dont drive the car or rev it, it will only yeild poor results with the maf unplugged.

 

[slow5.0gt]

well its hard to keep it on when its cold started after a couple of hours should I warm it up first then unplug and see if it starts up fine?

 

[myslo50]

try adjusting your tps voltage and your idle. there is a thread in here on how to adjust the tps and idle. plus with the new ecm, it also has to relearn? just things to look into?

 

[myslo50]

forgot also poss that it could be a sticky iac or maf or egr valce

 

[Mr. Rustypwnz]

try pulling codes and see what you get, could be alot of things wrong, or just a act sensor. yea I would try the maf unplug test with the car warmed up.

 

[HISSIN50]

A sig is helpful. We dont know if you have a 1600 HP quad-turbo beast or a near-stocker.

I'd be going over things like the IAC, idle adjustment and lookin for vacuum leaks. You can run a cylinder balance test while you retrieve codes - this helps narrow down if a misfire is from one particular cylinder or more of the random variety.

Good luck.

 

[jrichker]

As suggested...

Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a
jumper wire or paper clip to put the computer into test mode. Start
the engine and let it go through the normal diagnostic tests, then
quickly press the throttle to the floor. The engine RPM should exceed
2500 RPM's for a brief second. The engine RPM's will increase to about
1450-1600 RPM and hold steady. The engine will shut off power to each
injector, one at a time. When it has sequenced through all 8 injectors,
it will flash 9 for everything OK, or the number of the failing cylinder
such as 2 for cylinder #2. Quickly pressing the throttle again up to
2500 RPM’s will cause the test to re-run with smaller qualifying figures.
Do it a third time, and if the same cylinder shows up, the cylinder is
weak and isn’t putting out power like it should. See the Chilton’s Shop
manual for the complete test procedure

Here's the link to dump the computer codes with only a jumper wire
or paper clip and the check engine light, or test light or voltmeter.
I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

For those who are intimidated by all the wires & connections,
see http://www.actron.com/product_detail.php?pid=16153 for what a
typical hand scanner looks like. Normal retail price is about $30 or so
at Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes
or beeps.. Cost is $33.

See "Help me create the Surging Idle Checklist" at http://forums.stangnet.com/showthread.php?t=534062
for help with your idle problems. The first post contains all the updates to the fixes. I continue to update it as more people post fixes or ask questions.

 

[slow5.0gt]

I have seen both on this forum about that you can set the idle by adjusting the TPS Ive read both I remember in my hunt to find out what the problem was with it not starting was that I adjusted the TPS but used the ground on the car itself not the wire. IAC has been cleaned and what/where is the ACT sensor? ECT sensor?
Sorry for noob questions

 

[jrichker]

ACT = Air Charge Temperature Sensor. Normal location is in # 5 intake runner. It tells the computer the air temp so that the computer can calculate the proper air/fuel mixture.

See the link to the surging idle sticky I posted. Everything you need to find & fix your idle problem is in there, including the TPS adjustment proceedure.