Any Bosch Spark plug aficiando's !

[rswift]

Just tried to replace the plugs in my perfectly running LPG 4L Jeep Cherokee.

Ordered from Euro-carparts via the reg check thing.

The ones that arrived are R9's. Purely by coincidence the ones I removed are R9's, I didn't know they were Bosch until I removed them.

So, it won't run at all with the new plugs, and since I broke one on removal it runs on 5 cyls now that I have replaced the old ones.

The only difference I can see is that the old ones are marked '788' and the new ones '205' . Any idea what this number refers to ?

I have checked the gaps, which appear to be OK...

[ch427]

I would have thought that it was just the part number, is the thread length the same as the old ones?

[neiljohnson]

Once you know which cylinder swap one of the old plugs in & see

I've seen numerous faulty bosch plugs from euros of late for some odd reason

[Locknut]

This is a strange one! I did a search on Bosch spark plugs for a 1990 L6 and it seems to be giving American references that are totally different to yours:
http://www.boschautoparts.com/VehiclePartFinder/Pa...
As already suggested, check the length first.