I'm having a few problems with my s4 rx7 running really rich below 3k rpm. It has a T04 turbo which doesn't start working till after 3, but it seems as though it freaks out the standard ecu & dumps alot of few fuel. Once you boost it abit you can tell that its running cleaner. I'm thinking about installing an apexi SAFC to reduce the ammount of fuel before 3k, so it runs cleaner & much more economical for daily driving. Currently I'm only getting about 100km from 20ltrs taking it really easy. Ithink the extra fuel at low rpm is also causing my cold start problems. When I first start up in the morning, the revs flucuate quite abit and its smells extremely rich. Once the eng temp reaches approx the normal operating temp the problem dissappears. I think that too much fuel is being injected @ cold start & it lifts the revs, & then the comp tries to correct it. This makes the revs drop & the comp goes back to the original cold start fuel map, which injects to much fuel, the revs lift & it all starts again. Well thats my thoery anyways. Have any of you guys experienced anything like this, or could give me some advice. I'm definitely going to get it dyno tuned soon, hopefully with the SAFC.

 

How do you know it's running rich? Have you had it dyno'd?

 

I though it was running rich because of how it was bogging down low & for the fact it smells really strong. I took it to a mate of mine, who builds & races mainly small block chevs, and he took it for a sin & was certain it was running rich. You can also smell the difference when you boost it and it starts cleaning itself. I've gotta get it dyno tuned sometime soon, but was wondering if anyone had some constructive input on the matter.

 

You're running a T04 with the stock ECU???


-Ted

 

Yeah, it just the standard ecu with some plugins like FCD. Its quite laggy at the moment, but once its in boost there's still plenty of the rev range to work with. just gotta keep it in boost, at the moment its good for a 13.3 @ 10 pounds.

 

I'd be more worried about that set-up running lean, not rich...

Anyway, the best way to tell is to have it dyno'd, and get the mixtures logged. A big turbo won't cause the engine to run rich, so there may be a problem elsewhere. Have you checked for any ECU error codes?