mikeyb

car was running fine until after i raced a 300zx tt on highway. now i have a very rough idle and sometimes it stalls out on me. suggestions on what it might be?

mikeyb

also i forgot to add that i am getting horrible gas mileage too. about 40 miles and its down a 1/4 tank already. i have no clue whats wrong.

DaleClark

iTrader: (55)

Checked the vacuum line going to the MAP sensor yet?

Dale

mikeyb

no not yet. im gonna bring it to a shop and put it on a lift where i used to work cause i have to fix an exhaust leak too. but i will check that line when i get there. any more suggestions?

dgeesaman

iTrader: (7)

Check the MAP hose now. It's right in front of the driver, on the firewall, above the brake cylinder. Lift the hood and peek in there - it's labeled Pressure Sensor or something like that.

If that isn't it, I suspect blown engine. So do a compression test at the shop.

rotoboy661

^^^ i sencond that

u dont need to bring it to the shop, just see if the hose pop off the map sensor

exhuast leaks are not a big deal, can do that later

mike

kuroi FD

by the way how did you do against the 300zx? also check on your O2 sensor

mikeyb

checked the vacuum line going to the MAP sensor (i think it said boost sensor--line coming from throttle body and hooked up to the sensor) was ok. i need a new exhaust gasket but i can get that for like $10 from local mazda dealership. but anyways thats not the main problem. could it be a loose/ split vacuum line in the rats nest thats causing the problem as well? will check on the O2 sensor as well tomorrow. thanks for the replies. and didnt fare too well against the 300zx didnt kick my *** but slowly walked me.

dgeesaman

iTrader: (7)

O2 sensor is unlikely - the ECU only uses it during light/no acceleration.

Since you have checked the map connection, just suck it up and get the compression test done first.

Mahjik

iTrader: (1)

Do you have a vacuum/boost gauge installed?

If not, get something to check your idle vacuum. Also, as dgeesaman suggested, get a compression test done before you rip anything apart.