ColoradoBill

My guage reads around 1.1 or 2 Bars at max. Is that normal? FYI the motor has under 60K miles and is generally tight and in good shape.

AutoXdriver

[quote]Originally posted by ColoradoBill:
<strong>My guage reads around 1.1 or 2 Bars at max. </strong><hr></blockquote>

1.1 or 2? That's quite a spread. Let's refer to positive pressure only, so that would mean how far your needle climbs above the first (middle) bar. Normal boost on a stock 951 is around .75 to .8 bar, at least that's what I hear. Mine hits right at .8 and its got 117K on it. Of course this is just from the stock boost gauge which can be inaccurate.

Bill_396

Mine reads about 1.7 bar or 10 psi on the Autometer. Stock w/113K

Toolmaster

ColoradoBill -

Perhaps a slight rewording of your original post is in order.

Do you see 1.1 to 1.2 bar on the car, or 2 bar on the car?

1,2ish bar is in limp mode, meaning there's a problem. 2 Bar means you have aftermarket chips in there, with aftermarket boost control.

HTH!

ColoradoBill

Sorry. I meant 1.1 to 1.2.

So sounds like I have a problem.

Where do I start looking?

yoyoguy2

i'd start looking at an aftermarket boost gauge, or at least take it to a shop to hook up to one. just a good idea to check out before you look into anything else.

good luck

Toolmaster

If you're that low, you have a problem.

Could be any number of things.

Does the bar buck at all? Is the CV valve (between intake runner 3 and 4) connected? Any smoke out of the tailpipe? Any idea what your fuel pressure is? Do you have a catalytic converter on the car? Do you have any intake leaks?

Many more questions... Maybe see if you can answer the above ones.

HTH!

2+2

To share, my 951-s was boosting only to 1.65 bar or so. My tech clamped all signals to wastegate to see if the car will boost higher. It did not. He next took out the cat section of hte exhaust and replaced it with a gutted cat one. It boosted to 1.9 bar. He says that either the cat is plugged or the inner wall of the double wall exhaust pipe is starting to collapse which is a common problem in 951. He showed me one from another customers car which about 80% of the exhaust was blocked by the collapsed section. Apparently, that car was boosting to about 1.1 bar!! Check it out. Now I have a test pipe from GHL and boost 1.9 with 2 peak!! The car is soooo fast and much easier to drive! Good luck.

hrk

You might also check throttle position sensor. Stock chips limit boost at 1.2 bar unless they see full throttle.

ColoradoBill

Ré the potential Cat problem, can I remove the cat and start the car to see if that's what it is or do I need a test pipe to test it (which I guess would be pretty logical!)

2+2

Bill, you can remove the cat and fire her up but you better not have any neighbors or they will hate you. You also need to build boost so you will have to drive around to load the engine and build boos. With no exhaust, that's going to be loud. You ever been to a race??!!!

Robby

I had a simliar prob w/my Turbo S, but it wasn't as drastic- it was more random, and I would see 1.4 or in the 1.8 range (on stock gauge)- my prob was the throttle pos switch, as someone else pointed out...

tjbreen

I had a similar problem with my '87 turbo recently. It was late and I was using the boost a lot when I heard a pop sound. Boost dropped to 1.2 max and the fun was over. A couple of days later I had a chance to look for the cause of the pop and found the vacuum line to the BOV was not connected. I plugged it in and started it up. The problem has not returned and I am very happy. Not sure why that would do it except to say that I think it is time to replace the 15 year old vacuum lines.

Bill_396

2+2, I had a little extra time Friday night and was just looking for a reason to use my new hoist I installed last weekend so I raised her up and sawed out my cat. Also checked the double wall section while I had it off. Had some spare 409 tube and bends and welded it in in place of the cat. Did have a leak in the donunt at the entrance to the cat also. Work completed but still only boosts to just shy of 10 psi. Maybe the wategate is just tired. I do have a new deltagate II that I need to fab adapters for and also another stocker I just got off e-bay while I was thinking of taking the Lindsey conversion route. Anyone have any thoughts on this? Also found a big leak where the cooler line exits the axle, 1/2 gallon low, close call.