Hey HT, I have a 2000 Integra get with sri,ebay 4-1 header, itr cat and ebay catback exhaust. Problem is I'm having a heck of a time diagnosing the issue. When I start the car it immediately Gos to 1000 rpm then slowly rises up to 1500 rpm, it runs a little rough at idle, it feels down in power and it won't rev past 7000 rpm (yes it's fully warmed up and vtec works fine). I already checked fuel pressure which was actually very good, my vacuum pressure at idle is pretty firm at -21inhg, I've replaced both o2 sensors with oem sensors, I replaced the injectors and fuel filter. I replaced my header because my last one had cracks. I also replaced fpr and ecu. So here's the thing whoever had the car before me extended the tps connector, they also solderd the wires to the fuel pump connector (it looks ugly but there all connected well. Main relay has been replaced also. My short term fuel trim at idle is between +27 and +30 while long term fuel trim is roughly +20. Weird thing is my map sensor is reading roughly 4 psi which seems pretty low to me. Every now and then I get a p0420 code as well.If anyone has any ideas or has had the same problem PLEASE post. Thanks everyone.

 

Maybe tps and map is switched and or has a short in the tps wiring they re did. check thermostat ground as well. The code is for the cat, check for exhaust leaks around the header collector and cat. and make sure your o2 sensors are connected to the right plug one should be under the car hanging down and one coming off the engine harness above the header collector area. Other wise try another cat!

 

Hey thanks wunfstgsr. The tps and map connectors are proper. I have leaks where the cat meets the b pipe, where the collector meets the b pipe and where the cat meets the resonator pipe but there all fairly small. The o2 connectors are where they should be also.

 

definitely fix those minor ex leaks those could very well be your issue then reset the ecu, unplug it or the negative battery for a few mind the check engine light should disappear unless you have a scanner just erase the codes and go from there, I got one for $30 at harbor freight comes in handy I tell ya. if the problem still exist look into removing the cat for a good one. There is used ones you can find for a good deal if you search around.

 

https://honda-tech.com/forums/acura-...think-3228825/

 

Thanks HondaPartsHero, my fuel pressure is strong though. Has anyone here had a lean condition caused by a bad map sensor? Also the connector for ecu sensor was messed up so I had to snip the connector and run the two individual wires to the power and ground on the sensor and never got to rewire it properly with a new connector off the harness. Since I can't rev past 7000 rpm I'm thinking that might be the issue. I'm wondering if my ebay 4-1 header is causing a false reading with the 02 sensor. It's got big runners and a 2.5 inch collector.