1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 Okay, narrowed it down... still didn't pull codes, but here's a bite. Number 5 cylinder spark plug instantly coated in carbon black after starting... causing the cylinder not to fire. Plug is new and there is plenty of spark to the cylinder. This is the only cylinder that is having trouble. Testing fuel injector and power to injector now. Wondering if a cam lobe could cause a problem like this? Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Okay, narrowed it down... still didn't pull codes, but here's a bite. Number 5 cylinder spark plug instantly coated in carbon black after starting... causing the cylinder not to fire. Plug is new and there is plenty of spark to the cylinder. This is the only cylinder that is having trouble. Testing fuel injector and power to injector now. Wondering if a cam lobe could cause a problem like this?clean and swap for #4 and see if the problem folllows the plug or the cylinder. Link to comment Share on other sites More sharing options...
1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 clean and swap for #4 and see if the problem folllows the plug or the cylinder.Changed plug three different times and all fouled out instantly. All other cylinders are fine. Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Changed plug three different times and all fouled out instantly. All other cylinders are fine.bad #5 wire? black indicates poor spark to me unless you mean oil black. good compression and black plug.... doubt if it's a lobe problem. Oil fouled, very bad valve guide/stem seal maybe. Does it change from cold to warm at all? Link to comment Share on other sites More sharing options...
1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 bad #5 wire? black indicates poor spark to me unless you mean oil black. good compression and black plug.... doubt if it's a lobe problem. Oil fouled, very bad valve guide/stem seal maybe. Does it change from cold to warm at all?Changed plug wire with one that was working before and same thing. It's 15 degrees now and when started it's sputters hard, but stays running... after warming up, it doesn't sputter as bad, but the plug is fouled by then, and only four cylinders are working. In my earlier desperation move, I poured gas into the cylinder and black oil was stuck to the spark plug shaft hole. Could this excess oil be fouling the plug? Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Changed plug wire with one that was working before and same thing. It's 15 degrees now and when started it's sputters hard, but stays running... after warming up, it doesn't sputter as bad, but the plug is fouled by then, and only four cylinders are working. In my earlier desperation move, I poured gas into the cylinder and black oil was stuck to the spark plug shaft hole. Could this excess oil be fouling the plug? not sure i follow this. certainly if it's fouling that fast you have a cylinder problem. Still could be the injector if it's all carboned up though. try swapping two injectors. Link to comment Share on other sites More sharing options...
1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 not sure i follow this. certainly if it's fouling that fast you have a cylinder problem. Still could be the injector if it's all carboned up though. try swapping two injectors.Swapped injectors, getting fuel, same problem. When I pull plug wire, no change in idle, but plug is definately firing. Something is telling me that internal damage exists. Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Swapped injectors, getting fuel, same problem. When I pull plug wire, no change in idle, but plug is definately firing. Something is telling me that internal damage exists.thats strange, i would expect low compression or an overfueling injector. I guess it could be a busted oil ring or a very very bad guide/seal to be pumping that much oil. Know anybody with a borescope? We use them on high horsepower diesels to inspect cylinders without tearing engines down. It gets pretty involved on a 4000 HP Mitsubishi 65 liter 16 cylinger engine. It certainly doesn't look good for you though. I have to ask the question then...... Is your car silver? You could always call Justin.... :o Link to comment Share on other sites More sharing options...
MrWinkey Posted January 25, 2009 Report Share Posted January 25, 2009 Run a compression test on #5 cylinder Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Run a compression test on #5 cylinderI thought the same and looked back and he said 155-165 across the board. Doesn;t seem right though. Maybe try a cold and hot compression test too. Link to comment Share on other sites More sharing options...
1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 Run a compression test on #5 cylinderDoing it now... should have results in 15 - 20 min. Link to comment Share on other sites More sharing options...
MrWinkey Posted January 25, 2009 Report Share Posted January 25, 2009 I thought the same and looked back and he said 155-165 across the board. Doesn;t seem right though. Maybe try a cold and hot compression test too.Well if he's got 155 to 165 all across then it's spark or fuel? Possibly a wide open vacuum leak on that intake runner but never seen that? Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Well if he's got 155 to 165 all across then it's spark or fuel? Possibly a wide open vacuum leak on that intake runner but never seen that?suck squeeze bang and blow, fuel fire and time. That's all it takes!he's already swapped out injectors and plugs and wires and the problem is following the cylinder, not the accessories. If he's fouling on fuel, no spark, fouling on oil, then severe oil leak for it to foul right away. Sure seems like he's missing something here. Watch the comp test come back with 35 lbs or something. cross our fingers for the guy ;) Link to comment Share on other sites More sharing options...
1996 850R Posted January 25, 2009 Author Report Share Posted January 25, 2009 Doing it now... should have results in 15 - 20 min.Cylinder compression from 1 to 5 is 165, 165, 165, 152 ,150. Link to comment Share on other sites More sharing options...
64pvolvo1800 Posted January 25, 2009 Report Share Posted January 25, 2009 Cylinder compression from 1 to 5 is 165, 165, 165, 152 ,150.just for kicksw and giggles, have you tried two different "old" wires on that cylinder? I'm just still leaning toward weak/no spark. Any chance you knocked a tip of the cap when you put it on? Link to comment Share on other sites More sharing options...
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