slight hesitation,high speed miss.3000 rpms.

[02wgn]

Hello people,I have a 2004 taurus wagon with a 3.0litre engine,it seemed to of developed a slight hesitation and seems to misfire at around 3000rpms.thinking maybe ignition coil, new plugs and wires in 1/07.thanks for any help. 02wgn

[shorod]

Welcome to the forum!

Is it the 24V DOHC Duratech engine or the 12V OHV Vulcan engine? Both are 3.0 liters.

If you have access to a scan tool that can monitor the PIDS/CIDS/Component Parameters, check the individual cylinder misfire counts. Also, if it is misfiring often enough, you should get a check engine light which will help pinpoint the area to investigate. Most auto parts stores will check for diagnostic codes at no cost. They probably won't be able to pull the PIDS/CIDS/Component Parameters though if the check engine light has not come on.

-Rod

[02wgn]

Rod, thanks for the reply,its a 3litre vulcan engine,curently there arent any codes,is there any way to check coil with ohmeter,she will only misfire when you accelerate hard. thanks

[shorod]

Often there are specifications for primary and secondary coil resistance. I don't have a service manual for the 2004. You may want to check Autozone's website in the Repair Information section to see if they have the specs there.

-Rod

[02wgn]

rod my mistake,its a 02 wagon not 04,hence the name.robert r

[shorod]

I don't find a spec for the coil primary and secondary resistances in the 2002 service manual. The troubleshooting steps just describe how to check the coil driver circuit and then the coil for secondary output. If you don't have a scope, checking the coil driver circuit will be a bit tricky.

-Rod

[tripletdaddy]

I too don't have an exact spec to an 02 Taurus, but comparing values of several years, I think these should get you by enough to decide if it's ok.

Spark plug wire resistance approx
5000 ohms per foot or 400 ohms per inch

Ignition coil resistence
primary 0.3 to 1.0 ohms
secondary 6.5 to 11.5 k-ohms

I assume this is a coil pack. Pull the wiring harness off the coil. Test the four pins for primary resistance. One pin is the negative and the remaining three are the positives for the three coils inside. The coil will have "paired" plug wires, with a total of three pairs going to it. Pull the plug wires as they are paired and test across the two contacts for secondary resistance. You need to check all three pairs. If any measurement is out of range than it's no good. I also like to test to see if anything is grounded out by checking for continuity from the nine positive points to ground. I also like to look for oil leaks and burn lines, cracks,etc. removing it for a full exam.

[02wgn]

Thanks guys for the replys,took off the coil the other day,checked for shorts,resistances etc.everything normal,power tested it with a coil tester and found some external leaks,wiped it down,and reinstalled it,seems to be ok now,maybe replace it in the future when i get some extra money. THANKS GUUYS FOR YOUR HELP ROBERT R.