No boost....

[Pats-GN]

Hey guys, car starts, idles, runs great until you get into the boost, then it falls on its face, runs rough and misses. I can hear the turbo spin but can't build any boost, just wondering if someone can point me in the right direction. Coil pack and module are fairly new, stock turbo, stock maf, thanks

pat

 

[meanchicken]

Make sure your hoses from the MAF to the turbo, to the IC, to the intake are tight and none have holes or have come loose.

Also check to make sure your waste gate actuator has not come loose.

 

[NorEaster]

cat

Hey guys, car starts, idles, runs great until you get into the boost, then it falls on its face, runs rough and misses. I can hear the turbo spin but can't build any boost, just wondering if someone can point me in the right direction. Coil pack and module are fairly new, stock turbo, stock maf, thanks

pat

Check your cat, mine was doing this early this year.

 

[SHADOWII]

Check the ....

maf by lightly tapping on it. if the eng. stumbles, it's bad and the performance will get worse. Any air getting in behind the maf ie a hole in the pipe or loose connection as previously stated, will cause simular problems. pull off the maf pipe from the turbo and check the turbo shaft for play and freedom of rotation just in case the bearings are coked or worn.
If all this checks good, after checking the waste gate operation,you will have to pull the down pipe and check the puck to make sure it functions and hasn't slipped down from wear and isn't closing on the bypass, allowing the gases to escape past the puck.
Hope this helps.

 

[meanchicken]

Something else comes to mind since you mentioned that the ign module and coil pack are relatively new.

Make sure all the nuts/bolts holding your ingnition module to the base and the base to the manifold are tight, and that the connector to the moducle is tight.


Are you getting a check engine light when it happens or does it just nose over and chug along?

 

[Pats-GN]

Thanks guys!! I'm not getting an engine light, just when i get into the boost it starts running rough

 

[Evans Ward]

Do you have a spare known good MAF you can try? What are your Scanmaster numbers for AF at idle and WOT?

 

[meanchicken]

Most likely an air leak somewhere then...

Check all vac hoses...EGR valve...waste gate...etc.

Did this just start suddenly?
What happened just before it all started?

Details help with understanding...

 

[Pats-GN]

I've been slacking, had not driven the car in a couple months then I take a for a spin and noticed the problem. I believe it is the original maf on the car, i'm gonna try and check out all the hoses tommorrow, hopefully its something simple. I sure do appreciate the help, i'll let you know what i find.

 

[Rafs-T-Type]

Check the hoses with your hands....don't just look at them. I had a hose come loose on the up-pipe and and looked fine, but it was letting air in on the bottom where you can't really see.

 

[meanchicken]

Maybe one of those Bama swamp rats ate a hole in your air filter while it was parked for all that time and now his butt is stuck in your MAF pipe...

...or maybe he just chewed a hole or two in some of your hoses...

 

[Brady87GN]

Maybe one of those Bama swamp rats ate a hole in your air filter while it was parked for all that time and now his butt is stuck in your MAF pipe...

...or maybe he just chewed a hole or two in some of your hoses...

Now you'll need to by the rat-butt removal kit from RJC.

It never ends with these cars...

 

[Pats-GN]

Maybe there nesting in my MAF pipe :biggrin: True brady, it really never ends with these cars, i'm always chasing some kind of problem

 

[BIGPSI]

Check your cat, mine was doing this early this year.

x2 on the cat, mine did same thing years ago. simple to check,unhook down pipe at turbo,then start and see if she builds any boost

 

[turboc87gn]

Make sure ur not out of gas!!!! My maf went out and it ran the same way as yours...Two weeks later it was doing the exact same thing but this time i was out of gas!!!! My tach is mounted on the column and it blocks my fuel gauge!!!!