Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: RERX7 on April 29, 2010, 11:49:31 AM

Title: Engine problem help!
Post by: RERX7 on April 29, 2010, 11:49:31 AM
the car start fine, but when the idle is very low, it stay about 500 or less going up and down not stable, and smells lots of fuel at the bk of the exhaust, also the boost gauge idle bounce up and down too, any one know what is happening? i will try to upload a video late. thx guys
Title: Engine problem help!
Post by: ad4m1 on April 29, 2010, 12:04:14 PM
sounds like symptoms of chipped or broken apex seal. check map sensor hose is on as first port of call
Title: Engine problem help!
Post by: neil_jdmr on April 29, 2010, 02:16:15 PM
Vacuum leak from any one of the hoses around the tb i suspect. The boost guage will only be bouncing because your revs are fluctuating. The vac leak is causing your idle rpm to be so low that the car is struggling to keep running imo
Title: Engine problem help!
Post by: RERX7 on April 29, 2010, 07:38:48 PM
so i have to check all the vac hose see if there are any leak is that right?, also how can i check see if the apex seal is broken?
Title: Engine problem help!
Post by: JamietypeR on April 30, 2010, 01:25:33 AM
are u running an after market ecu?
Title: Engine problem help!
Post by: m1tch on April 30, 2010, 07:30:17 AM
Are you running an air pump still? I am on mine and it smells really rich as the air pump is pushing air into the exhaust and is going past the 02 sensor which then thinks that the engine is running lean so it dumps more fuel in, which then get air added in from the air pump and then it thinks its running lean so dumps more fuel in etc lol

I could be something like the TPS being off and it is hunting - unless of course you have a bridge ported engine :rollin
Title: Engine problem help!
Post by: SiH on April 30, 2010, 08:22:33 AM
Quote from: m1tch;690618Are you running an air pump still? I am on mine and it smells really rich as the air pump is pushing air into the exhaust and is going past the 02 sensor which then thinks that the engine is running lean so it dumps more fuel in, which then get air added in from the air pump and then it thinks its running lean so dumps more fuel in etc lol

I don\'t know about the FC, but if the guy has an FD, the air pump feeds in downstream of the lambda.

I\'m not entirely convined that this wouldn\'t be the case on the FC either - it would be a rather large oversight on the part of Mazda I\'d have thought...
Title: Engine problem help!
Post by: RERX7 on April 30, 2010, 10:03:22 AM
no it is a standard ecu, trying to tell my fd to upload the video on youtube and put a link on here ,  the one i got is an fd