car runs strong but bad gas mileage

[racin-type]

Yes i've been bothering you guys alot lately since i've just bought my 1995 S14.

The car starts good, runs good, idles good.

However it has really bad gas mileage. i get about 220 miles to a full tank, so like 14mpg. I also have an exhaust leak between the second dummy cat and my Blitz catback exhaust, so i can really smell the fumes. And then i have a DTC for my cat and now i think about it probably was caused by the rich condition.

Car stumbles sometimes around 1-2k rpm depending on how hard the gas peddle is pressed, i think this has something to do with it being rich. Car idles perfect except anytime i put a load on it like defogger/defroster or steering while parking, then the idle bounces a little then settles down. I'm thinking this may be an indication of some sensor that is going down hill.

Maybe my car is always in cold start mode? what kind of simptoms would that problem show?

Thanks so much.LO

ps - What is the normal NGK spark plug for my car? ending with 5C-11, 6C-11, 5G-11, 6G-11?

[s13sr20chris]

i dont remember the exact plug number. my sr uses bkr7e's if thats any help. try looking that up on our sponsors page http://www.sparkplugs.com i would mess with the maf and maf connector. specifically clean them out with brake cleaner. be very gentle.

also, look at the coolant temp sensor. when it fails it can cause the car to run very rich.

[racin-type]

i've tapped the maf and wiggled the wires but nothing. I'll try to get some maf voltages soon to verify. been too cold to do anything.

Thanks for the website for the spark plugs.