[shawnpbigelow]

Just wondering if anyone has bought any of the off brand cop on eBay? They have some complete sets of 8 for under 100 bucks. I just have never heard of some of the brands.

 

[cliffyk]

From what I have heard and observed it is a crap shoot, with a 50/50 chance of long term success.

When creating my COPTesto-The-Destructor COP tester (see below) I asked people to send me bad COPs for in-depth testing. I received a bunch, including two sets of "eBay" specials each of which had one or more COPs fail in 20k miles or less as reported to me. Most of what I received were aftermarket COPs, Accel, MSD, Granatelli, etc.

Do you have a bad COP? In general if they work without problem they are not bad, or weak, as they are just high voltage transformers. Ford stated in a notice to dealers, asking for them to do better testing, that over 50% of the COPs replaced under warranty and returned to the factory had nothing wrong with them.

COPTesto (testing a WeaponX COP):

I call it "The Destructor" because firing a COP repeatedly in rapid sequence, and dumping 100% of its energy across a large gap, will cause it to overheat and burn out. The stock COPs can take 24+ such firings before burning out, most after market COPs are all done in 15 to 18 full dumps. In normal use a COP only discharges a small fraction of its full charge.

Some of the COPs I received:

In this photo is a set of Weapon X standard units with 5 burned out, a couple of burned out Accels, and front and center one of the "eBay" COPs.

Here is a video of a stock COP firing across a 16 mm air gap...

 

[shawnpbigelow]

Thanks for the info. I am thinking that I have a bad cop cause after the car warms up, I develop a miss when accelerating at lower rpm. I have changed plugs and that didnt help.

 

[cliffyk]

Thanks for the info. I am thinking that I have a bad cop cause after the car warms up, I develop a miss when accelerating at lower rpm. I have changed plugs and that didnt help.

A sticking EGR valve can do that without throwing a code, how many miles on the engine?

 

[shawnpbigelow]

116k. I never thought of that. Should I turn it of with my tunner?

 

[02PONY]

The last 4-5 sets I've gotten have been off eBay

8 cops for $70. Can't beat that

 

[cliffyk]

The last 4-5 sets I've gotten have been off eBay

8 cops for $70. Can't beat that

Did you run many miles on them?

 

[02PONY]

I'm not sure about a couple of them they were in cars i flipped but I have them in my f150 and in my mustang when my msd's went bad

---------- Post added at 05:13 PM ---------- Previous post was at 05:12 PM ----------

Flipped as in I buy and sell cars all the time

 

[cliffyk]

I'm not sure about a couple of them they were in cars i flipped but I have them in my f150 and in my mustang when my msd's went bad

---------- Post added at 05:13 PM ---------- Previous post was at 05:12 PM ----------

Flipped as in I buy and sell cars all the time

The ones that were sent to me had 20k to 30k on them when they burned up, I had a set of Accels in which 5 burned up in over a span of 6 weeks at 25k miles or so.

There may be some "flippees" out there "flipping" you one right now

 

[02PONY]

I've got atleast 20,000 on the cops on my truck

I'm just saying its a decent to good alternative to get a full set of 8 cops vs 1 maybe 2 other brands
I like to replace all of them when one goes bad

 

[shawnpbigelow]

I was just a little leery. Usually you get what you pay for with car parts.