95 318ti power/revving issue
 

ok I have a 95 318ti that runs and does fairly well at a idle and when its cold it will go to about 3000rpms and cuts off like it is hitting a rev limiter and once warm it will only do 2500rpms. They car sat not running with a security issue before i got it and fixed the problem. I have already changed the cam sensor and did a complete test of the fuel system which checked out ok. The Tps is my guess and when i tested it i got some different numbers. Like under the sweep test the numbers i got decreased with throttle instead of increasing. But when i disconnet the tps it is a lot doggier but it still has the cut out at 2500rpms. I also tried unhooking the air control plug and hose from intake and tried running it that way without success. I will be changing the tps but my question what else could be causing this because i dont even have a check engine light coming on.

I am wondering if you hook-up the scanner and I hope you getting failure code. Also, while scanning for code, try to look the live feeds (activities) such as the TPS. Try to clean the TPS. How about the vacuum hoses, check for leaks. The last option is the DME/ECU. I have issue before with my 323, at idle works perfect but when revving the engine, I got a rough, sounds like misfiring. At first, I thought the TPS but it responded perfectly with the scanner when accelerating. So, I decided to replace the DME/ECU, and EWS with key chip. Check this site and read the symptoms of bad DME/ECU.

Clogged cat converter. My only guess since you state you are loosing more power as the car warms up. When these clog typical symptoms are 3000-3500 max RPM and as the converter warms up it clogs the exhaust flow more.

95 would be OBD I, right. That won't give you an error code for a failed cat like OBD II does.

We had one member on this board 98 318ti with no catalytic converter efficiency error code but he was having issues like you that kept getting worst. Converter fixed it. My neighbor down the street had a Bronco with same issues, no power and got worst the longer he drove it. He decided to punch a few 1" holes in the converter and he has been fine for about 1.5 years, a little louder.

You can test for a clog by disconnecting the exhaust off the header and tie the pipe up under the car real well. Yes it will be very loud but it will run great if you have a exhaust clog. This is the only advice I have for you.

John S

John, I am wondering what it cause for the clogged-up? Thanks.

They get hot and the web inside cracks then clogs the converter. If you looked into one you would see what I mean by the web or honey comb structure inside the converter