I'm getting about 100 miles a tank!! I thought it would have something to do with the loose injector pigtails but I replaced those and still.. too much gas.

It doesn't run very well unless it's warm... and still its not perfect. It pops sometimes (I think that might have something to do with the blown muffler) on deceleration, and stumbles on acceleration sometimes. It won't pass smog and I have only about 2 weeks left to tune it to pass. Any ideas?

-Steve
http://www.geocities.com/stev240z

 

hi steve.

your car is running way too rich. proof of this is the lack of good mileage. also, if it pops, here is what is happening.

excess unburned fuel is being dumped into your exhaust/tailpipe. it then gets heated to the point where it combusts in the tailpipe, resulting in popping, more known as backfiring.

Find ways to check your Air Flow Meter, TPS, and Fuel Pressure Regulator. all 3 of these are the suspects in horrible gas mileage.

this was happening to me, and i blew valves because of it. the valve head is designed for combustion. the valve stem isnt. when the unburned fuel ignites in the exhaust, it is combusting on the valve stem because the valve is closed.

fix it quick or you will probably go through a head. its *almost* up there with detonation. yikes!

david karey
socalz prez

SoCalZ Prez
http://www.socalz.org

 

hmm... i got an extra FI manifold complete in my garage.. maybe ill try swapping the TPS and fuel regulator and see what happens. I got another AFM somewheres too... does anyone know the proper way to adjust the AFM?

-Steve
http://www.geocities.com/stev240z

 

Check the coolant tempature switch as well. It also tells the computer how much fuel to supply to the motor. If it takes a [censored] the car will run rich.

Joey
1976 280Z 2+2
2+2s are not ugly

 

Well, tonight I whipped out the spare FI manifold and swapped in the cold start valve, fuel pressure regulator, and throttle position sensor. (Not new, but I figured worth a try.. since I had the parts already.)

Tonight on my way home from work I was racing a co-worker in his Dodge Truck... while getting on it it was cutting and popping on decel... not all that great and it was warm.
I got home, and swapped the parts out, and took it for a spin... and it wasn't quite at perfect operating temperature yet but not cold... and it was great! No popping at all, smooth acceleration, and more power. It seems not to be running rich or "choked" anymore, and I figure the mileage will be up to par now.

Tomorrow morning, 6 AM, we leave for the MSA show. It's running great, better then it ever did before, and we'll see if the mileage goes up now. With all luck, mileage will be good and it will pass smog now (after I install my new catalytic converter I got from autozone.. I dont want to put it on until the engine is running well, it can get ruined).

I'll let you guys know, I know you won't be able to sleep until I tell you )


-Steve
http://www.geocities.com/stev240z

 

hey im happy for ya! please show me your car so i can look out for you. i would like to meet as much people as i can tommorow!

david karey

SoCalZ Prez
http://www.socalz.org

 

cool, yeah, look for me... click on the link to my website to see pics of the car. my girlfriend and i are also on there. if the site doesnt work... check my profile here at zdriver, look at the 280z, not the 240z, the 240z is staying home this year.

of course, you could always email me stev240z@aol.com

-Steve
http://www.geocities.com/stev240z

 

the convertible ey?

thank god an easy car to find. i have so many cars to look out for its not even funny. i hope that the show actually floods out of Collins onto main. that would be cool!

SoCalZ Prez
http://www.socalz.org

 

NOPE, still 10mpg! it runs great... good enough for me to get a nice speeding ticket sunday night!, I'll post as soon as I figure out the problem... MIGHT be a clogged catalytic converter....

-Steve
http://www.geocities.com/stev240z

 

i remeber that your tps was unplugged. i unplugged mine for kicks on the way home from the MSA and it ran much better and pulled what seemed like twice as hard. nice meeting you yesterday. lots of cars to see and not enough time.

SoCalZ Prez
http://www.socalz.org

 

yeah you plugged that tps back in and plugged in for the drive home. i was really hoping that it would affect my mileage, but no.. i did actually notice some loss of power, tho! weird ha..

i still havent tried anything else yet... im getting tired of it so im gonna leave it alone for a few days. i need to focus on finals this week anyways.

anyone wanna buy a convertible? j/k

-Steve
http://www.geocities.com/stev240z