Engine Trouble

**Pursell1911** · 01-18-2017

How is the zzp not a real cat? Sorry for all the questions, I just want to get a better grasp.

**Scottydoggs** · 01-18-2017

its a hi flow cat. you need a real oem style cat to not set off the cel.

**Pursell1911** · 01-18-2017

Oh okay, thanks for clearing that up. Aside from the CEL, are there other disadvantages to going with a high perf cat? Some ppl say go with zzp, others say go oem. Just not sure which route to go.

**Bronco Boy** · 01-18-2017

Originally Posted by Pursell1911

Oh okay, thanks for clearing that up. Aside from the CEL, are there other disadvantages to going with a high perf cat? Some ppl say go with zzp, others say go oem. Just not sure which route to go.

For my '02, this is the cat I used, and it passed our CA like emissions testing..... http://chrisb.users.superford.org/Gr...Converter.html

**Scottydoggs** · 01-18-2017

if the hi flow cat sets the cel, you'll need to deal with that. one way or another you need to to not set the code so its running its best.

either a tune, or simulators, theres another type of plug in thing that tricks the o2 as well.

oh and you'll need a o2 extension harness if you get the zzp dp. they moved the o2 bung further.

**markpa** · 01-18-2017

Depends if you don't mind looking at the check engine light. Also if you have remote start it will not work with a check engine light on.

Sent from my iPhone using Tapatalk

**Below Average Joe** · 01-18-2017

Correct me if I am wrong. If you are revving up the engine, you are asking the engine for more fuel and more spark. Could this sound be a worn wire arching off something? Could be fuel related, but I'm just tossing out ideas. I've never heard that sound before.

**Pursell1911** · 02-03-2017

Just an update to this thread, my CEL codes have gone away. All I've done is run a few tanks of 93 octane and had to reset the battery for an additional issue. I've since put over 100 miles on the car over the past few days, and the CEL has not come back. Maybe running lower octane gas was causing the P0420 and P0455 codes to come on? The previous owner used nothing but 87 octane the entire life of the car. Maybe that's caused the loud noise I've been dealing with? Not sure, as I inherited that problem...

**FordMan77** · 02-03-2017

Well, if that vid was of knock from running low octane fuel then I'm surprised the motor didn't eat itself. The S/C cars need premium fuel so keep the 93 in it and monitor for issues. Hopefully the CEL is gone for good for you now.

**Pursell1911** · 02-03-2017

Yea I have no idea what that loud clanking sound is - It only does it past 3500 rpm. NFI!!! It's driving me crazy though.

**Pursell1911** · 02-07-2017

I'm sure everyone is tired of this post by now as it has sorta gone stale, but I have an update on the issue I've been having. Changed my transmission fluid and filter, and was just kinda seeing if I could replicate the unrelated (?) transmission issue I was having prior to changing fluid, and noticed that I was able to get the engine to 4000 RPM while going up a hill. The throttle was not wide open, I'd say maybe 75% or 80%. I noticed a hissing sound as I was approaching that RMP level, appeared to be coming from the passenger side of the engine bay. I'm not sure if any of this helps or not, but figured I'd post an update. I have been afraid to WOT in the event I screw something up worse.

**jimzssei** · 02-07-2017

Hissing ... I'd unbolt the downpipe from the rear manifold and see if it runs stronger.
It will be loud and possibly set a code, but will tell you if you have a plugged catalytic converter.