need help with mass air flow sensor.

[HOMEMADE240SXTURBO]

well we put my turbo in ka24et and my car started idling pretty low and would even died sometimes. when you floor it, it will spit spotted and then take of at 5000 rpm. so my friend brandon thinks that it is the mass air flow sensor acting up. so he would like to figure out the resistance on the mafs and bypass it with a resistor. what do you guys think?
Modified by HOMEMADE240SXTURBO at 3:19 PM 4/3/2007

[Cyclemut]

Unless it's going to vary with airflow, it won't work. The computer will need to see how much air is getting in there.

Try this instead. Just unplug it, and let it idle. The computer will go into a failsafe and allow the vehicle to run, but not above 2500rpm. But if it runs good until it hits that, then you know it's a bad MAF. Then find one in a junkyard, or ebay.

[HOMEMADE240SXTURBO]

beside the mafs, what else would make it died and spit spotted?

[Cyclemut]

A vacuum leak, or over rich condition. How does the exhaust smell when it's doing it, really rich?

[HOMEMADE240SXTURBO]

no the exhaust does not have any smell.i was thinking about mounting the maf right up intake manifold(throttle body) to see if it would get some accurate reading.b/c i'm thinking that the maf is too far away from the intake manifold and by the time the air get into the throttle body, there may be way too much vacuum leak from the piping. does it make any sense?

[Cyclemut]

If your piping isn't sealed up, then you're not getting proper boost anyway. Do you have a vacuum/pressure gauge? If so, then hook it up to a manifold vacuum sorce and see what the pressure is when it spits and sputters. If it's only reading 0 when it does it, then your piping is actually the cause.

If the engine isn't seeing enough boost, but doesn't have vacuum, then she won't run worth a darn. A friend had a similar problem on his turbo'd SR20.

We ended up thinking it was the turbo, but when I was on the way home, he called and said his clamp down by the intercooler had come off and that's why it wouldn't build any real boost at all. He put it all back on tight and it ran like a champ. So the piping is really important, so that you don't have leaks.

[HOMEMADE240SXTURBO]

alright i got it fixed up. it was just a bunch of vacuum leaks and a hole in the pipe somewhere. thanks for all the help.

[Cyclemut]

Sweet! Glad you got it running.

[RICERMAN]

When you alter the engines OBD11 system sensors you open up a can of worms. Why did you do that?

[Cyclemut]

Because stock sucks, that's why.

[RICERMAN]

An engine that wont run sucks more,,,,,

[Cyclemut]

But now it does run, and I never have that problem.