Caboose

Hey rennlisters, its been a while since I've posted here and I've just returned from a deployment recently. My 944T has been acting up recently after I had the radiator replaced because the old one was original and finally cracked. My 944 feels like it builds boost but it does not deliver it.
To illustrate my point, when I give the car easy easy gas, it will slowly climb in RPM over 3000 but only using engine power. If I try to accelerate quickly at all the car does not deliver boost, it climbs to 3000 and then it "stalls" as if the car wants to go but the boosted air isn't getting into the engine. I'm not too car-literate when it comes to turbo-charged vehicles and am really at an impass on how to solve this one. I'm not scared to try and tackle it myself as I have gone as far as changing an oil pan gasket on this car and would like very much to have my boost back.

Oh and I also have the Lindsey racing boost enhancer. It was on the car when I bought it and I haven't had this issue before.

Please advise,
-Jordan

Van

Maybe the AFM is unplugged... maybe there's an air leak in the intake plumbing (since that would have all come apart to do the radiator. Or, at actually sounds like it could be a loose hose clamp on some of the intake plumbing - and when you're under boost, the joint separates and lets all the "boost pressure" out, but when you're not on boost, there's enough vacuum in the system to hold it all together.

So, that's where I'd start checking things... with the eleventy-billion intake hose clamps.

Black51

It's also too simple to not change the spark plugs to see if that fixes it too.

zerMATT951

Is the car stock? What mods? Just the LBE?

I agree with Van, check for intake leaks first. Anything that would allow compressed charge air out would cause a problem like that. From there, maybe an exhaust restriction... Clogged cat, collapsed down pipe liner, crossover liner, etc...

Willard Bridgham 3

Wow, that's a lot.......

carlege

I would pop the hood and check the turbo impeller blades. Make sure all the clamps are on and then check for exhaust leaks.

ilikemy944

I agree with some of the above - you probably have a big air leak somewhere.
Check every hose - especially those to the intercooler, those like to hide the fact they've cracked.

Caboose

What are impeller blades?

I'll be able to look over the car pretty soon. What the best method for checking for air leaks? I'm not sure how to go about it.

-Jordan

carlege

I think it would be best to spend a couple hours identifying your self with various parts of the car. Use the site. Look at pictures i spent 2 years doing that before i even decided to buy the car. You have some catching up to do. Your car and the fact its 20+ years old requires you to have deep pockets or a willingness to learn aspects of the car.

Google search a turbo and look at the google images. A picture is worth a thousand words.

Righty tighty, Lefty loosey and take your time. Dont force anything.

Good luck and have fun.


Checking for air leaks can be tricky. remove the J boot and inspect it for cracks. you will need to remove it to check the turbo impeller. Look at all the hoses and clamps (best to take pictures if you get too far and think you will get lost when putting it back together)

Alot of a car is common sense. No need to be scared of it. If you have a hard time sliding a hose on dab a little oil on it and it will slip on very easy, various other tricks out there.

Gotta ask when was the last time your timing belt was changed?

Van

Start with this:

dizzyj

I did this very thing last week. I used a piece of 1 1/4" pvc, a cap, and a coupler. glued that all together and drilled the cap to fit an air compressor attachment on. I then disconnected the hardpipe coming from the turbo to the intercooler, and connected my pvc. It very quicky showed where I had a vacuum leak (my intercooler was bad). it was very easy to do.