stopping boost creep

[Big_P]

I just bought an 88 LeBaron GTS. Previous owner installed a 2.5" exhaust and promptly sold it before using it.

The boost goes up to 12, then promptly goes up to 20!! I'm surprised I don't hit cut-out. I do NOT want to blow this motor up.

How can I stop this? The motor is completely stock.

What can I doooooo?

Thanks.

[turbovanman²]

What are you using for boost control?

[Big_P]

Whatever the factory uses. The solenoid, I assume.

Right now I have it plumbed into the intake mani, I'm getting 6psi and no creep.

Slowwwww.

[turbovanman²]

Check for the restrictor on the wastegate hose and make sure the vacuum lines for the solenoid are routed properly.

[Big_P]

I installed a home-made MBC. I went to the Deep Homo, erm, home depot, and got a teensy valve and plumbed it in. Anyway...I got it tuned to about 14psi...

However, as soon as I bang 2nd gear it stays at 7psi, spikes to 10, then stays at 7 again. This is so weird. It's been a long, long time since I've had a Turbo Dodge (that ran).

[Big_P]

BTW, it's a TII with a 555 tranny.

[turbovanman²]

I installed a home-made MBC. I went to the Deep Homo, erm, home depot, and got a teensy valve and plumbed it in. Anyway...I got it tuned to about 14psi...

However, as soon as I bang 2nd gear it stays at 7psi, spikes to 10, then stays at 7 again. This is so weird. It's been a long, long time since I've had a Turbo Dodge (that ran).

If the boost was solid using just manifold vacuum then your controller isn't very good. DId you remove the restricter?

[Big_P]

the MBC i used went straight from the brake booster to the boost controller, to the wastegate.

I don't know what restrictor you speak of.

I'm about to just throw some +20's and an A/F meter on it and let it boost to it's hearts content.

[turbovanman²]

the MBC i used went straight from the brake booster to the boost controller, to the wastegate.

I don't know what restrictor you speak of.

I'm about to just throw some +20's and an A/F meter on it and let it boost to it's hearts content.

You didn't answer about the 6 psi?

The factory puts a bleed/restrictor in the wastegate line.

[Big_P]

If the boost was solid using just manifold vacuum then your controller isn't very good. DId you remove the restricter?

Does the restrictor look like a normal vacuum line barb?


Well, if so, I did not bypass it, I just replaced the hard line with a rubber line.

would it be beneficial if I removed the restrictor?

[turbovanman²]

Does the restrictor look like a normal vacuum line barb?


Well, if so, I did not bypass it, I just replaced the hard line with a rubber line.

would it be beneficial if I removed the restrictor?

Remove it when running a MBC.

[Big_P]

K. Done. Removed.

Boost is set to 12psi. Runs good up there.

I noticed the 2.2 likes to rev a lot more than my 2.5.

I get 12psi in 1st gear, but only about 7 in the rest of them. Am I doing something wrong?

Sorry to bombard you with all these questions, Simon, but you're the only one that is willing to give me some advice. I'll stop soon, I promise.

[mcsvt]

Possible boost leak I'd say. Or weak wastegate...

Have you tried the "disconnect WG" test? Did the boost sky rocket?


As a side node you should have bought a car that had this sorted out already

[Vigo]

hmm, that statement leads me to believe you are part of the 99% of people here who can find turbo dodges to buy. congratulations. please send a turbo dodge to San Antonio, Texas asap.

[turbovanman²]

K. Done. Removed.

Boost is set to 12psi. Runs good up there.

I noticed the 2.2 likes to rev a lot more than my 2.5.

I get 12psi in 1st gear, but only about 7 in the rest of them. Am I doing something wrong?

Sorry to bombard you with all these questions, Simon, but you're the only one that is willing to give me some advice. I'll stop soon, I promise.

I'd venture to guess at a crappy MBC or it could be the wastegate is getting weak. Have you tried a vacuum pump on the wastegate to see if she'll hold?

No worries about the questions, this part I am a bit hazy on but can help I think,