Hi, I just purchased a '96 Si. A week after I had it the engine light came on and I noticed a low RPM miss, and a rough idle. I took it to the dealership and found out it had a 150,000/14yr warranty on emissions. They changed the oil (which i had done right when I got the car) the plug wires,plugs and ignition rotor. The problem was gone. Now, two weeks after that the light is on again. I can't feel or see anything wrong with the car, I'm scheduled to take it back in on tuesday (4-5 days from now). I looked around the car, couldn't find anything. I did find that the Cat converter's heat plate was rusted off and was being held on by the back two bolts, causing a small rattle at low R's.

Do you think that the light can be due to the conveter some how?

Is it safe to drive?
I don't want to damage anything, but nothing seems wrong at all.

Thanks

 

could be your cat, i just installed a new one and got a engine light b/c of it.

go to autojoke and get a free diagnostics test, they should be able to tell you your problem.

 

When the ck engine light came on, what code were you getting? What was/is the ecu telling you is wrong? Is the light on when you start the car or does it come on after the engine warms up? etc., etc., Tell more about the symptoms you had then and have now. I have a similar problem and think I have a combination of a few different problems. Am trying to eliminate the symptoms one at a time.

I'm not trying to hijack your thread (I have a post here about my problems), but with mine it runs good until warmed up. Then the CEL comes on and it starts missing. I can turn the switch off, restart the car (now the engine is warmed up)and it will run good again until the light comes back on in a few minutes, then misses again. Codes are for egr (which has been removed and cleaned), O2 sensor (which has been replaced) and fuel delivery system (new fuel filter put on). I bought a new throttle body as a mechanic that looked at the car said the voltage was "all over the place" from the TPS. Replacing the TB didn't help the other problems and now I have surging idle in addition to the other problems.

 

hoe... it can be your cat but most likely not.. those heat shields always come loose and cause ratteling noises.. you can remove them but kind of illegal due to the supposed fact taht they can cause your car or the grass to catch on fire
lol
but no damage can be done other then killing gas alot quicker .. your car is probably running rich .. i had the same problem it was my o2 sensor.. but on a 96? the tune up was most likely your most reasonable cause.. since o2s dont really burn out that quick..
id take it back to the dealre since you say they have the 12 year warantee.. is that for every honda prelude everywhere? or did it have some sort of extended warantee cuz id go get a free tune up too if it were true for all dealerships in north america
and for kb.. thats harsh dunno what your problem is man seems kind major if soo many people have messed around with it and no one has found the problem yet.. or maybe the problem was that too many people changed too many things..
id change the cat and get a motovac .. lol thats probably the only things you havent done in my eyes that could still get you that code

 

Before the 'tune up' I had the same problem. It was fine until it got warm, then it started missing and the light came on. They replaced the plugs,plug wires and ign. rotor. It has ran fine since. Now the check engine light is on again, I can't find anything wrong. The guy at the dealership said the warranty was only for Preludes and only for 96-97's. My question is, is a rusted heat sheild enough to cause the light to come....how would that trigger anything?!?!

 

dont think the heat shiled has anything to do with your check engin light man..
your cat just pretty much dilutes the gases that are not good for the environment..
check engin light wont come on from that heatshield being too rusty..
but maybe your cat is just too old... lol
dunno if there is a proper way of testing..
usually just knock it with a screw driver see if the thing rattels (not the heat shield the cat.. heatshields are usually torn off long before a cat goes out)
but it get it scanned and see exactly where its being triggered from..
if its not tune up / emissions dunno what else it can be from not tooo familiar with the trouble codes on hondas yet..

 

you have to let us know what code its throwing so we can help