Cold running conditions

[Repostyle]

Okay, when I start my car in the mornings it has a hard time idleing until the temp comes up just the slightest bit (about 30 seconds at 1500 rpm). It will then idle, rough but it won't die. Until it comes up to normal temp it backfires and has trouble just keeping a speed, I can let off the gas and it goes fine or be heavy on the gas and it goes just fine, but just trying to maintain a speed with just a little throttle and it spits and sputters. A friend of mine says get new or rebuild my injectors (stock 19#). Another friend says EGR. What do you guys think? Keep in mind, it runs perfectly fine (no noticable problems) once it comes up to temp, and no engine lights come on.

 

[qcrun98]

My stang seems to do the same thing but takes forever for it to idle correctly. I am leaning toward the fuel injectors since I have an aftermarket cam with the stock 19# injectors trying to feed all of the fuel to the engine. I am swapping them out with some 26# injectors this winter with a Cobra upper & lower intake. This should solve the problem but its hard telling with FI. Try getting the injectors professionally flushed that worked when my Explorer was having the problem. Good Luck.

 

[jrichker]

Dump the codes and see what the computer says is wrong. Even if the Check Engine Light isn't on, there can be problems lurking in the dark...

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.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

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 AutoZone or 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 $35.

 

[dyb003]

I had pretty much the same problem with my Lincoln Mark VII and it would stall all the time cold but once it was worm it was fine. I also had no check engine light but when i pulled the codes it said bad EGR valve. I replaced that and the sensor that bolts to it and now it fine. Starts right up cold and no more stalling. You may want to also clean out the throtal body inside as when they get a carbon build up it will give you an eratic idle. It was about $110.00 for the EGR stuff from Auto Zone. They can also pull the codes for you for no charge if you dont have a code reader. Good luck

 

[Repostyle]

Yeah, I've already tried hooking up the scanner but it doesn't show any trouble codes. It was a couple months ago so I can't remember if it's 2-digit or 3, but it was showing okay with no problem codes. That's why I'm trying to get some opinions on what I should spend my money on first, new EGR or rebuild my injectors or something else all together.

 

[HISSIN50]

Another thing to check is the calibration of the ECT. If it is telling the puter your motor is hot when it is cold, the idle will suck. JR has posted values of the ECT thermistor at various temps.

Good luck.