A year ago I replaced insulators, caps, and rotors with new Bosch components. A few months ago I began chasing a “hiccup” where the car would suddenly cut out for a split second, especially when warming up and under load. Eventually, this deteriorated into four cylinders not firing. EZL modules have caused this symptom but changing that did not make a difference; nor did a new coil. As a last resortI examined the distributor cap and found what appeared to be a dusting of brass contacts and a badly pitted rotor. The four “posts” were badly grooved. For comparison I examined the other cap and found it pristine. Any idea what causes such rapid wear? A bad cap? Fortunately, I located a replacement cap and rotor in stock at a local auto parts warehouse which appear to be Beru. The car ran perfectly with the parts.
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Bad Cap and Rotor
- Thread starter Phoenix127
- Start date
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Unfortunately this photo is after I cleaned off the debri inside the one year old cap. I felt the wear was excessive. Somehow it rendered all four plugs inoperative. I purchased the set of Bosch caps from FCP Euro in September 2019. Not sure of build dates... wish I had taken more photos...
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You can find the production stamp on the front side of the cap where the wires plug in.
I am investigating the Bosch caps and would appreciate your input.
I now have a 10/2018 production cap and just received a 12/2016 cap. both look Identical so I am not sure if this is part of the "bad batch"
The photo is too small to view any possible damage to the cap. Might have just been a fluke defective cap and/or rotor. As mentioned in other threads I had a brand-new Bosch cap that caused a hot misfire at idle only, replacing with another new cap cured it. After this bad experience with Bosch ~6 years ago, I switched to only buying Beru caps/rotors/wires.
BTW, seriously bad caps appear as shown below. Yours looks pristine by comparison!
I once installed a brand new Bosch cap which appeared to be cracked! And I did not abuse it during installation due to the brittle material in it. Bosch have had quality issues with their caps for years. I've seen several incidents both on this forum and elsewhere, both on caps and coils. And I don't think Bosch has any plans to do something about it because this is an outgoing part, modern technology took over years ago.
