Check engine light woes

[john9001]

Originally posted by Skilless
It is absolutely impossible for a gasoline engine to run with the distributor cap removed.  And before you come back and say something like "Yeah, but it really did", I will say again; It is absolutely impossible for a gasoline engine to run with the distributor cap removed.

had a car run with the cap removed from the dist but the HT wires were still pluged into the cap, the spark was arcing between the coil post and spark plug posts( bad cap) it did not run very good , but it ran.

i had to call the other techs over to see it, if you work on cars long enough (40 years)you will see everything.


on the eng light, check the code, thats why they put it in there.

[AWMac]

Recheck the Henway and make sure it's balanced properly.

Then ask your Dad if driving a Ford "Probe" makes you look Ghey.

[WhiteHawk]

Originally posted by dmf
My Tempos eng light comes on when I start the car and never goes off.

yea.  I had a mercury topaz for about 5 years and the checl engine light would come on every 15000 miles.  It used to scare the crap out of me like I was gonna break down at any minute.  i tried everything I had the capacity to do.  Plugs rotors wires sensors distributor cap.  (mine needed this to run  ) , nothing helped.  But it would always go off after about 3500 miles.  I figured it was a ford gimmick to get you to bring it in for one of those costly 'encoder digitizers'.  I logged over 130000 miles on it, sold to my wifes nephew for 500 bucks and it is still running with over 200,000 miles on it.  Best car I ever had.  
  Never did check the engine:p

[Scootter]

Wife had a company car (Ford Torous) left the gas cap loose, called me to tell me check engine light was on. I told here to take it to the Ford Stealer (ahh Dealer). What did I care her company paid for everything car related, they tightened the gas cap and the light went out in ten minutes or so. Seems to be some emission related thing.

Check the Gas cap, really

[eskimo2]

Originally posted by nirvana
Alright for you car guys try to grasp this one.  My step dad said he disconnected as well as removed the distributor and the engine still ran.  What can I say besides he was pulling my leg or my car is MESSED up.  Possible computer problem.

Some engines can “diesel” for awhile after the ignition is shut off, especially if the anti diesel valve is not in place.  I suppose that if an engine that’s prone to dieseling is already running and hot, and the cap is pulled, it might keep going, for a bit…

eskimo

[mora]

Which trouble code it was, or to what component was it referring to? Was it a constant or occasional trouble? Is the engine running differently than before(idle speed, lack of power etc.)?

[mora]

Originally posted by eskimo2
Some engines can “diesel” for awhile after the ignition is shut off, especially if the anti diesel valve is not in place.  I suppose that if an engine that’s prone to dieseling is already running and hot, and the cap is pulled, it might keep going, for a bit…

eskimo

I once put some diesel(1/1 ratio) to one of my old gasoline cars on purpose, just to see how it would run. It did keep dieseling after I turned ignition of when the engine was hot, and I even got the damn thing moving!

[nirvana]

See that's what i'm thinking it was doing, dieseling, but i'm not sure.  We'll see if it pops on again in another week.


And the trouble code kept changing they (my step dad and lead mechanic) said, so it's hard to tell.

[ROC]

Guys in the shop were tuning one of the trucks.  Engine light stayed on.  Replaced the 02 sensors, new plugs, wires, the works.

Engine light was still on.

They were stumped.

I told them to clean the battery terminals.

They looked at me like I was a moron.   Honestly, I can't argue with them on that, but they still needed to clean the posts.

They did.

Light went off.

They have never heard of such a thing, cleaning a battery post to turn off the light.






Still haven't told them that when they disconnected the battery cables, they reset the computer

[nirvana]

That's cheating ROC.

[dmf]

ROC thats just mean LOL


I wish that was teh problem with my car, I took it to Pep Boys yesterday and they told me I need a new computer, I don't see how since my car runs fine, and doesn't that computter thing control the engine?

[WhiteHawk]

booooooo..dont you believe it.  If the damm car is running then the puter is fine.  You DID change the spark plugs right?  If the ignition system is dirty or worn,  it will send erratic messages to the puter and this will cause the check engine light to come on, and rightly so.  Change the spark plugs, wires cap and rotor if applicable, and see if that doesnt fix the proiblem.(tune-up)

[mora]

Originally posted by WhiteHawk
booooooo..dont you believe it.  If the damm car is running then the puter is fine.  You DID change the spark plugs right?  If the ignition system is dirty or worn,  it will send erratic messages to the puter and this will cause the check engine light to come on, and rightly so.  Change the spark plugs, wires cap and rotor if applicable, and see if that doesnt fix the proiblem.(tune-up)

That's exactly the problem with many "professional" shops today. When they have no clue  they keep changing and charging for unneeded parts, and by luck they might get it working. Ignition for example is easy to diagnose with an oscilloscope. I do agree that the ECU is not a likely fault here but not impossible. I don't think the engine management system in a car of this age is capable to detect misfiring... If the motor is running fine by ear it's unlikely that the source for the trouble code is ignition.

[mrshiver]

Originally posted by Golfer
My first car was a 1994 Grand Am

You guys make me feel so old. My first car was a 55 dodge.

[ATA]

You can be sure that its not the gas cap,'96 ford probe does not have EVAP......i think