| Author | Message | ||
     Mark Tennison New User Username: fixstuff Post Number: 9 Registered: 11-2020 |
So thanks to all for help so far, nearly out driving ! So fuel lines de-goo'd and renewed where required, primed fuel pump and turned the key, started and runs very quiet however, it has a misfired not really tried much so far as run out of time today but would like any suggestions for tomorrow. Note: New spark plugs have been gapped(0.030) and installed, no change. Many thanks | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2410 Registered: 09-2004 |
Is the miss fire the same hot and cold? Could be the start of the opus electronic ignition failing. On a simpler note it might be a HT lead! | ||
| Mark Tennison New User Username: fixstuff Post Number: 10 Registered: 11-2020 |
Patrick, May be my imagination however, I feel that immediately after start it seems to run smooth without misfire but a second or 2 after start misfire is apparent and constant and I would say rhythmic not adhoc/random. Cheers | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 664 Registered: 11-2017 |
Bring the car into a very dark location and look for subtle arcing from the leads to ground. Although not precise, you may get lucky and see arcing. Old wires are a problem. Another overlooked area is the dist cap and bad rotors that arc. Check for vac leaks which are common. Poor electrical connections are overlooked all the time and they are the non-obvious gremlins. | ||
| Mark Tennison New User Username: fixstuff Post Number: 11 Registered: 11-2020 |
Robert, Thanks for the tips, will have a full day on it tomorrow. All, Was thinking of using the HT spark probe to earth/ground/-ve to identify if misfire is associated with specific cylinders. Any thoughts ? Many thanks | ||
| Graham Phillips Frequent User Username: playtime Post Number: 339 Registered: 03-2019 |
G'day everyone,.... What Robert said,.... I would lean towards an ignition lead not snugly connected. Just my thoughts,... Graham. | ||
| Mark Aldridge Frequent User Username: mark_aldridge Post Number: 727 Registered: 10-2008 |
Mark, if you have a spare HT lead, try cylinder by cylinder substitution. I have had individual leads fail several times particularly in the metal sheaths. I no longer use the metal sheaths as on the post 1987 cars. | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 2411 Registered: 09-2004 |
Or scope it for time saving if you can access one. Or an ohms tester on each lead will confirm! | ||
| Mark Tennison New User Username: fixstuff Post Number: 12 Registered: 11-2020 |
By removal of each HT lead, I identified that 2 (1 on each bank) cylinders were not contributing as much as the other 6 however, by the time I'd finished trying different things and stop/starting the engine it gradually became smoother until by the end of the day it was running perfectly.! I guess the pre oiling of the cylinders as a precaution for the lay-up + a small amount of old fuel in the float chambers... may have contributed to the initial misfiring ? Was running that well we took it for its first short drive. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 743 Registered: 05-2016 |
Happy motoring, the more they're driven the better they tend to go. |
