Horrible Gas Mileage...Turbo manifold Related?

[Nevermore]

I am having horrible gas mileage on my girlfriends MSP.

would a cracked Thunder Manifold be the likely culprit of such bad mileage?

everything else on the car seems to be running up to par...

Suggestions?

 

[powderider87]

Does the mani stop leaking when the car is up to temp?

 

[Nevermore]

well I now the car jerks and wants to fall flat around 4k when boost starts to kick in, I think its more than likely the manifold but just want to make sure

 

[Nevermore]

so I have come to the conclusion that the car is hitting fuel cut...had the exhaust temporary welded today to close up the crack and it still does the same thing, how should I go about getting rid of the fuel cut? I changed the spark plugs recently to NGKs and just threw on a cheap spectre filter for now to get rid of the stock airbox...but thats it for "mods" thus far

Any suggestions?

stock MSP stock tune.

 

[Flspeed]

Take the vac line from your fuel pressure regulator off and smell it. If it smells like fuel or if it taste like fuel when you blow in it then its a bad regulator. Do you have a wideband?

 

[Nevermore]

no wideband, I could probably take the wideband off my 240 and try it on the msp.

I'll check the vac.

I wont be able to get to it tonight but if you have anymore suggestions so i can just knock them out one of the time that would be great. thanks

 

[Flspeed]

Gap the plugs down to about .32ish

 

[Nevermore]

I'll do that, I actually just got new plugs earlier some copper NGKs I read those are recommended for basically stock MSPs I had replaced the plugs about a month ago for Iridiums, so Ill gap them to .32 and go from there! thanks for your help flspeed

 

[mazdaspeedp]

U could try replacing the coils. Are u getting a cel? It might also be a bad o2 sensor or most likely her wastegate is bad if its never been replaced before u can get a cheap one from atpturbo.com

 

[Nevermore]

CEL comes off and on, was on about 2-3 weeks ago but went away and hasnt came back.

just changed the spark plugs, no dice still cuts out. will try the vac tomorrow...any other ideas?

 

[Flspeed]

Wideband...Wideband...Wideband...Gotta see was going on internally.

 

[01CrznMp3]

The cause of the flashing cel is from large misfire. I know a lot of people have problems with coils going bad. As far as gas mileage, cars eat more gas in cold weather, idk if you have taken that into concideration. My car has been suckin a LOT of gas here since its been cold. I get 220miles on 3/4 of tank when I fill up. I used to get around 260ish.

 

[Nevermore]

Its not the cold weather...were in south texas and its been a consistant 60-70 degrees

 

[Nevermore]

fixed the problem! dont know why I didnt see it but the stock BOV wasn't connected properly...yay for boost!

 

[jbrewer4639]

glad you found the problem

 

[Nevermore]

it was not the problem after all...

this wastegate Actuator...isn't there a TSB for it and Mazda has to repair it for free?

 

[jbrewer4639]

I have no idea but you could get a atp replacement actuator for 60$.

 

[hornsfan10609]

Mazda won't replace anything on these cars for free, I would get the ATP or Forge WGA.

 

[Nevermore]

this one?

http://www.atpturbo.com/mm5/merchan...&Product_Code=ATP-WGT-011B&Category_Code=VMSP