Problems hitting boost

[fifthgearvtec]

Hey guys, I have a '90 Plymouth Laser RS Turbo and I have a question.
I installed a manual boost controller, and bumped it up to 15-16psi and it ran great for about 2 months.
But after that it started hitting what I think is fuel cut.
It won't even let me boost passed 10psi anymore.
Only thing done to the car is 3" megan racing downpipe and o2 dump.
I just replaced all of the oil gaskets and gave it a tune-up.
Just wondering if you guys could think of possibilities of what else it could be.
Thanks in advance.

 

[freshlane]

how you have the bc conntected?

 

[TURB0]

Sounds very much to me like a huge boost leak. I don't see how you could be fuel cutting at only 10psi. Go ahead and give it a boost leak test...if you don't have the tester, just go through every piece of IC piping and re tighten all of the clamps. I've seen this happen on quite a few DSM's, it's no big deal. Good luck.

 

[MrBoxx]

How to make and use a boost leak tester. Hint: Spraying soapy water all over the intercooler pipes, TB, IM, etc. will make leaks easier to pinpoint.

What spark plugs/wires are you using? What boost controller? At what point in the rpm range is the cut occurring?

The most likely situation is fuel cut, so a boost leak test is mandatory at this point.

 

[silver bullit]

Definitly do a boost leak test, and have you changed over or accidently run the car off of 87 instead of atleast 91, 93, 94+ octane fuel. This to would cause the computer to put it in safe mode as low grade fuel causes the computer to sense and record knock, which is caused by crappy fuel and cut the boost back accordingly.

 

[fifthgearvtec]

Sounds very much to me like a huge boost leak. I don't see how you could be fuel cutting at only 10psi. Go ahead and give it a boost leak test...if you don't have the tester, just go through every piece of IC piping and re tighten all of the clamps. I've seen this happen on quite a few DSM's, it's no big deal. Good luck.

Well, it cuts everytime I try and go passed 10psi, .
It's a little frusterating.
But, thank you, I'll let you know afterwards.

 

[fifthgearvtec]

How to make and use a boost leak tester. Hint: Spraying soapy water all over the intercooler pipes, TB, IM, etc. will make leaks easier to pinpoint.

What spark plugs/wires are you using? What boost controller? At what point in the rpm range is the cut occurring?

The most likely situation is fuel cut, so a boost leak test is mandatory at this point.

Yeah, I was thinking a boost leak would be on the list of things to eliminate.
I'm using the Autozone brand spark plugs, . ---->
And I made the boost controller myself, but it seems to work fine.
The cut is occuring pretty much as soon as the turbo builds boost (14b by the way).

 

[fifthgearvtec]

Definitly do a boost leak test, and have you changed over or accidently run the car off of 87 instead of atleast 91, 93, 94+ octane fuel. This to would cause the computer to put it in safe mode as low grade fuel causes the computer to sense and record knock, which is caused by crappy fuel and cut the boost back accordingly.

Nope, that would make sense, but I'm the only one that drives this car, and I use 93 in my talon too.
Unless my dad jacked my car one night without me knowing, .

 

[oldman]

man I came too late.....oh whata hell

BOOST LEAK TEST!!!