Excel miss

Hi, I have an Australian Excel, 1998, manual, 1.5L DOHC, 150,000km. For a while now it has a miss on acceleration, clears up above 1800~2000 revs. Checked the engine codes 4444 (all clear). (Pre OBD2)
Had new plugs fitted, and the injectors serviced, made no difference. Checked the coil pack resistance, manual says should be ~500 ohms for twin cam or ~.5 ohms for single cam. Mine actually measures 1 ohm. My wife has a similar model so checked the coil in that, measures same as mine, hers runs well. What could cause this problem and not show up as an ECU code? TIA Wayne H.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Wayne H wrote:

Did you replace the spark plug wires? They're more likely to be the cause than plugs or coil packs.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Concur. Had a similar problem on another car. Given the age, change the wires no matter how good they look visually.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

maybe breaking down under load. Will get another set of leads tomorrow and try that, hopefully it will fix the problem.
Wayne H.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

resistance of each spark plug wire should be checked w/ ohm meter all the same? check compression after engine warms up. leaking/ stuck exhaust valve? compression leak? check static valve clearance?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Success!! but not quite what I expected. Had a thought, & decided to change over the ignition leads from my wifes car, made no difference. As I'd got that far and against the general opinion of the group I decided to try changing the coil pack over as well. - Ran like a dream, better than it had in over 12 months. Put my coil in wifes car, ran like a dog.
Going out tomorrow to buy myself a new coil.
Thanks to all for your advice, fortunately the motor wasn't making expensive noises ( burnt valves etc)
Wayne H.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I run a fleet of hyundais too!
Sure helps problem solving
Norm

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.