it stopped

hi im a newby ive had my 85 rangie 7 years now and had no engine trouble at all with her short of the yearley service not touched it. a couple of weeks ago she started running rough backfiring chugging& general lack of power . have checked usual suspects plugs dizzy rotor afm.a couple of days ago it just refused to start.today i have removed plenum cover and the 8 ports are covered in a black tar like gunge. can anybody tell me whats wrong desprate to stop walking trev

Sounds like plenum and throttle disc all gummed up and possible air leak - remove plenum and ram housing and thoroughly clean, check/set throttle disc. Might also be worth doing a compression test and checking/setting ignition timing.

Assuming it's a 3.5 flapper, have you still got the cold start injector connected?? Are your plugs wet and also looking a bit black and sooty?? Could be leaky cold start injector - disconnect and try starting it.

Hope that helps.

hi kev i did make an attempt at cleaning throttle disk last week and it looked cleaner in there untill i took the plenum cover off and could see in there properly i hadnt seen the amount of gunk behind the disk. i also noticed the cover had been sealed with silicone possible air leak. will remove and clean ram housing tommorow and let you know how i get on thanks trev oh yes it is a flapper & i will check the injector

The cover should be resealed every time its removed, so silicone here is normal. Although i'd use a high temperature gasket sealer

hi i have now cleaned plenum resealed with hylomar gasket sealer. checkedcompression all are between 150-160 psi found a coil wire to + broke almost in half coil lead corroded (green) inside coil head done those. now she's running again but roughly. try this one took her down the road every time i turn a corner she cuts out its auto so out of gear and starts on key easy very strange almost as if im nearly out of petrol and its sloshed away from the pump any ideas trev

....how much fuel is in the tank, if it's not full, fill it up.......stranger things have happened! Also i would check all the electrical connectors for fuel system are secure and check the inhibitor switch on gear selector....

hi lads i got it it wasn't fuel or air leaks & although it was a good spark at the plugs nice strong blue spark i put a new coil in this morning and she's good as gold again. i had suspected the coil early on but dissmissed it as there was a good spark. it just shows it/s hard too tell when a coil is breaking down? trev