91 300SE M103, new injectors, now harder start

[sixto]

I replaced the injectors (injectors, o-rings, seals, holders) of my 91 300SE. Idle is smoother but still not glass. Smooth at speed but not smoother than before. The trouble is that were it used to stumble for a few seconds when starting cold, now it catches and dies a couple of times before it stays running. The stumbling part is either much shorter or gone (haven't tried enough times to know for sure).

I suppose I should check the accumulator and pump check valve next, but does stalling on cold start indicate something wrong with the new injectors or their installation?

Thanks,
Sixto
91 300SE
87 300SDL

[sixto]

Is there any correlation between oil leakage past the valve guides and seals and plug condition in my 91 300SE? I'm definitely at the 1 quart or more per 1000 miles point but there's no oil my plugs after being in service for 2 years/12K miles. There are external leaks but nothing that leaves a puddle when parked.

Thanks,
Sixto
91 300SE
87 300SDL

[Mike Murrell]

Sixto:

Seem to recall reading a post here a good while back indicating that injectors needed to be bled down when replaced. Can't say I know this to be true.

Regarding the oil usage. We both have the same car minus 6 in. of rear leg room.

Just had head gasket, Infamous U-gasket at front of engine, timing cover reseal, valve cover gasket and valve stem seals redone. Tech was of the Brotherton philosophy that guides should be changed only if they are worn and not as a maint. item.
My guides were fine according to my tech.

Prior to this surgery, I had no oil on my plugs and was using approx. 1 qt. every 1,000 miles. Oil was dripping on floor from passenger side of head and there was a mess around the U-gasket.

After 1,300 miles, oil usage is ZERO.

[sixto]

The hard start is gone! I guess it did need to be bled.

Warm idle feels the same as before. Oh well.

Sixto
91 300SE
87 300SDL