When I occasionally downshifted to get around traffic or pass cars in the past, I did so with no problem. However, I've noticed that for the past few weeks my engine would start to bog down at higher rpms (like 5 or 6k). The motion experienced from my seat was mostly rocking back and forth, not extremely vigorous shaking like head banging or anything, but still a VERY noticeable rock.

At first, I had no idea what it was caused by, and didn't really seem to be alarmed, and since these days I rarely drive it at higher rpms the amount of occurrences were few and far between. But then recently, when I drove it harder, not only did it do the rocking motion, but my CEL started to flash for about 5 seconds. I tried it again the next day and it stayed on for about 10 seconds or so. Each time it would eventually disappear and I have full functionality of my car at lower rpms.

But I've tested it further and noticed that happens near redline in 1st gear... in 2nd gear it seems to happen at around 6500, and in 3rd it happens spot on at 5k. I've also noticed a very rough idle as of late and wonder what is causing this. I have 25k miles on it, I always fill it up with premium, and my oil level is fine.

What really confuses me is that it really drives like normal unless I rev it higher. I've been on the highway driving at least 75mph and its fine, it seems to be only related to my tach. Any ideas?

 

Clogged CAT ?

 

has you gas mileage started to drop???? have you ever flooded your engine???

but i agree it is proabably a clogged cat.

beers

 

Most likely. $100 says this car has flooded at some point.

I think there has been one single reported cat failure on the Australian Forum. You yanks have one every day, it seems. The connection here is Australian cars flood extremely rarely. We have different flashes, different fuel and different weather. When you flood, you fill the cat with fuel. When it starts, you burn the fuel in the cat and overheat it. Countdown clock then starts for cat failure........

Come to Australia.....the sun shines 24/365 .

 

rarely do i have fla usa sux rubbed in my face...

beers

 

Thanks for the replies, all. I don't seem to recall any symptoms of a flooded engine on any start up. black smoke, etc.. And i normally let my car warm up properly.

I DO KNOW, however, that my roommates have routinely moved my car from the garage whenever they need to detail theirs.. (usually early in the morning when i'm knocked out because obviously i could just move my own car otherwise) I doubt they let it warm up properly all the time. still though, wouldn't i know whether the engine flooded on any subsequent start ups.. or no?

i was thinking i just needed to get reflashed or something.. but either way i was going to the dealership. Still, is there anything strange about the fact that it bogs at the same rpms in each gear? Also, if it is a clogged cat, how cooperative can i expect the dealership to be with me? Thanks again.

 

get master tech to ride along with you. they do that for a living... if you can demonstrate it they more than likely can fix it.

btw, if it had been flooded you would know it . wont start..

beers

 

A lot of cars have flooded before you get them new. They are driven off the ship into a holding yard and shut off cold. They are loaded onto a truck and shut off cold. They are offloaded from said truck and shut off cold. They are shunted all about the dealership and shut off cold. They get a pre-delivery service and are shut off cold.

Pick any one .

 

Good beer here .

 

Could this be the spark plugs going bad? At high RPM's they aren't firing? I'm starting to have this at 7000RPM and I have 25,000. I'm thinking it's time to change the plugs.

 

My car did the same thing...I would hit about 5500rpm and it would hesitate. Then it wouldn't even rev above 7000. Like the engine hit a rev limiter. CEL would flash, or stay on.

Took it in and they replaced the clogged catalytic converter. After that, sounded better, and ran smoother, and had more power than it ever had before. I think that those that have not reflashed to later PCM version and still have the original cat will start to have problems like this. Too much fuel in the early fuel maps, now they have been leaned out, exhaust temperatures are a little higher and that cat gets cooked.

The CEL should point to the cat.

 

Yep... you called it. With a Yoda avatar I never shoulda doubted ya

Turns out the plugs needed to be changed.. according to the master tech, I don't rev my car high enough anymore =(

He told me that he replaced plugs and wires and mentioned something about an upgraded set of plugs, but don't remember anything about them (colder/hotter).. I guess the part no. is on the invoice if I ever need to know...

The drive home was fun.. I'm not limited to 4k anyomre (yayyy)

Thanks for the helpful replies, everyone