bad iddle on Grand marquis 94

[gm94]

This is getting annoying... I pull out the air intake elbow, clean the carbon deposits on the air intake area, i also replaced the egr valve and new gasket, replaced the spark plugs and put new plug wires on it. I replaced the O2 sensor also. i verified the gap for the plugs. Checked that the plug cables are making good contact. I cleaned the idde controller with some air intake cleaner. I put everything back together making sure that all bolts were tight enough. I also replaced the fuel filter. Clean the MAF sensor and air temp sensor.

I started my car and its even worse. Now the iddle is bad. It hesitates all the time. At night the headlights and dome lights pulsate. If i put it in gear gets even worse. i don't hear any vacum or air leaks.

The only things that i have left to try is get a new iddle controller, throttle position sensor and the egr solenoid. I'm running out ideas. I'm very frustrated because it doesn't make any sense.

I think this is something electrical but i don't know what to think anymore. I will have to use my last option... take it to a mechanic. LOL

Can anyone think of anything else? Please help me out!

[miamibob]

Hi!

This may SOUND stupid but did you put Dielectric Compound into BOTH ends of the Spark Plug Wires?? Fords will act like the symptoms you wrote of if you do not do this!! Anytime you remove the wires, from EITHER end, you need to do this. MB

P.S. This is a cheap thing to try - it's easy and you can get the tubes at places like ADVANCE Auto, NAPA, Autozone, etc....give it a shot before making yourself MORE crazy then you are now - Trust me - I've been there!!

[gm94]

Thanks for the reply and no it doesn't sound stupid, it makes sense . Dielectric grease help you get better conduction of electricity.
I'll try that and if it doesn't work im going to put the old spark plugs back just to see if i maybe have a bad one.

I tried this morning to scan the computer and it had a stored code of the MAF sensor voltage being high and low from yesterday night. Chiltons book says that if you check the pins "c" and "d" you should have continuity. Well it doesn't. I cleared the memory from the computer and it not showing any code now. So i'm wondering if this continuity test is correct... is the MAF sensor bad, even if i don't get a code or check engine light?

[miamibob]

Any sensor can be "slightly" out of spec and not put out a code. The MAF comes alone or as an assembly. The assembly cost about $200! There is a special spray for it - you can get it at PEP BOYS. You should not use Carb Cleaner or even Trottle Body Cleaner. Use the specific cleaner and DO NOT touch the little contacts inside or you WILL be buying a new one! Try the compound, recheck the spark plug gaps and make sure the wires are good. Hopefully, you will then spend more time driving and not repairing!!

[gm94]

Well im happy to say that the bad idle is gone. It was the damm spark plug wires (brand new) were not snaping good at the plug and/or at the coil. Had to cut a piece of the boot so they can reach the spark plug.

I'm still getting a small hesitation but way better than before. A mechanic friend of mine told me that for these cars he always buys the cables at the dealer because of that problem.

I think that my ignition coils are going bad. I read the chilton book and measured the resistance according to the book. I'm getting 0.6 ohms at the primary and 14.56k ohms at secondary. The book says that the minimum range for primary starts at 6 ohms and secondary maximum is 14k ohms. That's a big difference in the primary. Going to go to auto parts store and see if they have one in stock, so i can measure the resistance of a new one, just to compare.

If they are bad is going to cost me about 300 dollars for them (ouch) . But they are 12 years old, so i guess is time for a replacement anyway. I just got the car and it is in good condition. 130k miles only. I guess it will be a good investment. Thanks for the replies guys.

[Stevo2]

Originally Posted by gm94

Well im happy to say that the bad idle is gone. It was the damm spark plug wires (brand new) were not snaping good at the plug and/or at the coil. Had to cut a piece of the boot so they can reach the spark plug.

I'm still getting a small hesitation but way better than before. A mechanic friend of mine told me that for these cars he always buys the cables at the dealer because of that problem.

I think that my ignition coils are going bad. I read the chilton book and measured the resistance according to the book. I'm getting 0.6 ohms at the primary and 14.56k ohms at secondary. The book says that the minimum range for primary starts at 6 ohms and secondary maximum is 14k ohms. That's a big difference in the primary. Going to go to auto parts store and see if they have one in stock, so i can measure the resistance of a new one, just to compare.

If they are bad is going to cost me about 300 dollars for them (ouch) . But they are 12 years old, so i guess is time for a replacement anyway. I just got the car and it is in good condition. 130k miles only. I guess it will be a good investment. Thanks for the replies guys.

Email or look up your coils at this Ford parts house, you should be able to get your coils for $150.
www.nationalautopartsdistributors.com

[bdomarat]

Did yo change out the ign coils and did that have an affect? I have 92 with the orig ign coils.