Misfire after sparkplugs and both ignition coils replaced

[Stahl]

I had a few issues as of recent with my car that I thought would have been fixed after some part replacements, I replaced the MAF sensor, and both ignition coils as well as throwing in some Bosch Platinum OE Finewire spark plugs from RockAuto. Now my car has a pretty bad misfire to the point where it shakes the whole car and eventually stalls out. Anyone have ideas? There is a pretty poor condition spark plug wire that I found and I feel like it's the cause. Just checking for some insight here before I drop about 200$ for a new set of wires. Anyone else know if this problem is caused by anything else?

 

[gsxr]

The M119 with distributors do not like fine-element spark plugs (platinum, iridium, yttrium, etc) and also do not like resistor plugs. First thing I would do is install a set of the correct non-resistor Bosch F8DC4 plugs (or the new OE Berus now being supplied by the dealer), along with opening up the gap to 1.0mm on those plugs. I'm not sure if it will cure the issue you are having, but it's far cheaper than dropping $200+ on wires you may not need.

If the car starts & runs fine when cold, but misbehaves when it warms up (10-15 mins later), you may have the infamous issue with fluid on the back of the distributor cap insulators. Search the forum for many detailed threads on this topic.

 

[nocfn]

My guess was the plugs

 

[Stahl]

Alright thanks for the tips guys, I ordered some from RockAuto, dirt cheap. It'll arrive middle of next week; I'll give an update then.

 

[samiam44]

I would put the correct non-resistor spark plugs in the engine. What year is your car?

 

[samiam44]

I'd measure each wire and make sure you don't have a bad connector. If they are Beru, the 90 degree resistor ends are replaceable.

 

[jhodg5ck]

I'd measure each wire and make sure you don't have a bad connector. If they are Beru, the 90 degree resistor ends are replaceable.

While waiting for plugs this is a Good thing to do.

Just re-read...no caps and rotors??

MAF's hardly ever go bad....that was a pricey throw...

Jono

 

[Stahl]

Alright, good news and bad. The car runs a bit smoother, but it still has a misfire. A friend and I discovered oil inside of 2 of the spark plugs so that may be the real cause. I'm kinda screwed on this one. The car was running fine back in the winter months and now it's gone to hell. Oh well. I'll see where to go from here.

 

[gsxr]

Alright, good news and bad. The car runs a bit smoother, but it still has a misfire. A friend and I discovered oil inside of 2 of the spark plugs so that may be the real cause. I'm kinda screwed on this one. The car was running fine back in the winter months and now it's gone to hell. Oh well. I'll see where to go from here.

Where exactly is the oil? You can get oil in the spark plug wells from leaking valve cover gaskets... nuisance to replace, but not terribly expensive or difficult.

If the external insulator & hex of the plug is clean and it's the electrode that is oil fouled, that would be unusual.

 

[Stahl]

The oil was on the thread. May have been on the electrode as well.

 

[gsxr]

The oil was on the thread. May have been on the electrode as well.

Oil on the threads is nothing to worry about - if that was all you found, you can relax.

 

[samiam44]

Since it didn't miss-fire before R&R ing spark plugs. I've been in the junkyard and noted that many of the wires are broken @ the 90 degree connector.


M