I have a scanner, assumed no check engine light meant no code but I will scan. Good idea about using it to find which one is misfiring. Will do.

Thanks

 

make sure OBDII PCM is going into closed loop when coolant temp goes over approx 155d F

record fuel trim levels, primary O2 sensor voltage swing min>max
also record timing, should be 10 BTDC at idle and increase to 28 BTDC at 2k rpm

pull wire from IAC, engine rpm should almost or completely stop

double check to make sure all sensors are connected

the 2 scanners I have
http://www.autoxray.com/product_detail.php?pid=94
http://www.autoenginuity.com/products-scantoolpalm.html

clearing codes with a consumer retail reader or scanner does NOT clear the KAM in the PCM of faulty sensor readings or failed component operation, we only have the technique of disconnecting the neg-- batt. lead for 5 minutes to dump old KAM memory parameters

 

I agree, a scan tool can save you lots of $$$$. If you get the ELM 327 chip, It will read most vehicles, there are quite a lot of software which will work with this scantool. Another good one is Autotap (am I allowed to mention that?). Most of these have software which will include a "digital dash" you can monitor most of the sensors on the engine. You can graph them & also you can record engine conditions while driving & play back later , if you take a recording device with you, (or even a stopwatch ) you'll be able to note when the misfire was at it's worse. Since fuel trim can also be graphed you can compare readings when this occured. Freeze frame is a feature which is a saved set of engine parameters, which the EEC records at the time a code is set, so that you get a snapshot of what the engine was doing at the time the code was recorded.

I've had one about 4 months & it is definately an asset & will pay for itself over a short time. You can also reset the CEL & better software will calculate Engine load & HP, long & short term fuel trims, RPM, MPH, ECT, ACT, PW (Injector pulse width), O2 sensor voltage, AFR Dilution (with wideband O2 sensor only), ISDC (idle speed duty cycle) throttle position, Ignition timing, etc. You could have already made use of it so far!

ATB Aeroman.,

 

Got an 1443 Egr code this morning when I went out. Reset after the van warmed up and the code never came back for 17 miles. Will do more investigation and keep you posted.

 

Okl, after tracing out the EGR system found that the one of the rubber hoses that connects to the carbon cannister (below the air cleaner) had fallen off. Hooked up and car ran great with no hesitation or missing for about 300 miles. Now i have a new problem. Daughter was driving the other day and when cold the idle was screaming like 2000 rpm. I unpluged the idle air soleniod and the idle dropped way down. Basicaly if you start it cold you now have to partially push the acccelerator down. Once it is warm it is fine. I was going to replace the idle air soleniod but thought I should check first. Is that a positioner or an open close valve? If it is a positioner I could understand how replacing it would fix the problem.

 

it is a timed open closed valve that can be rapid variable timed opened by the PCM with variable timed DC voltage from the PCM

main stuck open failure is from dirt/PCV crud freezing piston
take off and soak in TB cleaner for an hour, often works and saves $$$$

also change PCV valve if older than 20k miles or loaded up with crud....do NOT try cleaning, the valve springs lose tension and the valve seat wears

 

Yikes-$45 at autozone, yes I think I will pull it and soak it. Thanks for you help. I will let you know how it went. TB cleaner, you mean toilet bowl?

 

throttle body cleaner
can of Berrymans B12 works also

only soak open valve end
do NOT soak electrical solenoid end

 

Ah ha.
Thanks

 

On some Ford IAC, the valve end can be separated from the solenoid. In that case, it becomes very simple. Just dunk the valve end alone.

I know that I can do this for my '95 4.0L, but not for the '93 3.0L. Maybe the '97 3.0L will be different.

 

I acutually had problems on both my 96 AWD 4.0 and my 97 2WD 3.0. The 96 cleaned up well and worked. The 97 was shot. $45 at Autozone for a new one. Works great. Thanks for your help.

 

My God, what did you put in the gas tank?