TWO Engine Misses - HELP

[Mavrick]

Motor is missing on cylinder's 4 AND 5... both have spark, but i don't know how to check the injectors.

How should i check if the injectors are firing.. and if they are, where do i go from here?

Thanks

 

[HISSIN50]

Mav, i would do a balance test. it is in the tests you do when scanning codes. it will check the injectors pulsing up to three different ways (if one test fails, it tries another way with different criteria).

or you could try using a noid light (or listening for clicking if you can reach the injectors). could swap the suspected bad ones for known good ones to see what happens.
i would do the balance test first. good luck.

 

[Notched]

ok im not entirely sure if im right. so dont take my word, hopefully someone can confirm me. I remeber in electronics class that we took a multimeter, or some powersource and hooked it up to an individual injector, and watch, and listen to see if we could hear it pulse. just waht i remeber, hopefully im right.

 

[Mavrick]

Ya, thats the same idea as the noid light... noid light = test light right?

I'll try that, will start looking for some different injectors.

 

[Notched]

oo.. my bad.. see u know more then i do. i should just stop offering help to people, since i suck

 

[Notched]

well actually no. i just re-read what u said. a multimeter is a 12v meter that can be used for ohm, volts, amps.. etc... if u set it to the right one, and touch it to the injector it should pulse once, or u should hear it move. if they are the same, then once again. sorry

 

[Mavrick]

well actually no. i just re-read what u said. a multimeter is a 12v meter that can be used for ohm, volts, amps.. etc... if u set it to the right one, and touch it to the injector it should pulse once, or u should hear it move. if they are the same, then once again. sorry

Same idea.. but i only have a digital multimeter, which is no good for measuring the pulse of a fuel injector as it is much to fast for the digital multimeter to pick up. If i had an analog gauge, it'd work nice but i'm going to go at it tomorrow with the test light.

 

[HISSIN50]

Mav, the test light might not accurately dipict the pulses. it will give an idea that the injector is gettin juice though. the balance test is more comprehensive.
good luck, Mav.

 

[jrichker]

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 99 for everything OK, or the number of the failing cylinder such as 22 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.